1. business and industrial
2. agriculture and forestry
3. crops and seed

Feeds & Feeding 1
GC
GREEN
CERTIFICATE
CURRICULUM
DPP
INDEX
TOC
Table of
Contents
Plant Growth & Composition
Plant Growth ................................................................................ 6
Plant Composition
Plant Carbohydrates ............................................................... 7
Lignin ...................................................................................... 8
Plant Lipids ............................................................................. 9
Plant Proteins ........................................................................ 10
Plant Minerals ....................................................................... 11
Plant Vitamins ....................................................................... 12
Feed Sampling & Analysis
Feed Sampling ........................................................................... 13
Sampling Hay ....................................................................... 14
Sampling Silage .................................................................... 15
Sampling Bulk Concentrates ................................................ 16
Sampling Bagged Feeds ....................................................... 18
Feed Analysis & Interpretation .................................................. 19
NIR or Wet Chemistry? ......................................................... 21
Dry Matter and Moisture ...................................................... 22
Microwave Oven Dry Matter Estimation ............................. 23
Acid Detergent Fibre ............................................................ 24
Neutral Detergent Fibre ....................................................... 25
Non-Fibre Carbohydrates .................................................... 26
Energy Estimates ................................................................... 27
Relative Feed Value .............................................................. 29
Relative Feed Quality ........................................................... 30
Crude Protein ....................................................................... 31
Non-Protein Nitrogen ........................................................... 32
Soluble Protein ..................................................................... 33
Acid Detergent Insoluble Nitrogen ...................................... 34
Neutral Detergent Insoluble Nitrogen ................................. 35
Rumen Degradable Protein .................................................. 36
Crude Fat .............................................................................. 37
Minerals ................................................................................ 38
Vitamins ................................................................................ 39
Silage pH .............................................................................. 40
Bulk Density .......................................................................... 41
Particle Size........................................................................... 42
Processing Index ................................................................... 43
Feeds for Dairy Cattle
Forages
Perennial Grasses .................................................................. 44
Smooth Bromegrass ........................................................ 46
Orchardgrass ................................................................... 47
Perennial Ryegrass .......................................................... 48
Tall Fescue ....................................................................... 49
Timothy ........................................................................... 50
Wheatgrass ...................................................................... 51
Annual Grasses ..................................................................... 52
Grain Crop Forages .............................................................. 53
Legume Forages ................................................................... 54
Alfalfa .............................................................................. 56
Red Clover ...................................................................... 57
Grains
Barley Grain .......................................................................... 58
Corn Grain ............................................................................ 59
Oats Grain ............................................................................. 60
Rye Grain .............................................................................. 61
Wheat Grain ......................................................................... 62
Oilseeds & Pulses
Canola Seed ......................................................................... 63
Flaxseed (Linseed) ................................................................ 64
Sunflower Seed .................................................................... 65
Peas ....................................................................................... 66
By-products
Beet Pulp............................................................................... 67
Blood Meal ........................................................................... 68
Brewer’s Grains .................................................................... 69
Canola Meal .......................................................................... 70
Corn Gluten Meal ................................................................. 71
Distiller’s Grains .................................................................... 72
Fats & Oils............................................................................. 73
Feather Meal ......................................................................... 75
Fish Meal .............................................................................. 76
Soymeal ................................................................................ 77
Mineral Supplements ................................................................. 78
VitaminSupplements .................................................................. 79
Feed Additives ........................................................................... 80
Feed Storage
Hay Storage .......................................................................... 81
Silage Storage ....................................................................... 82
Concentrate Storage ............................................................ 85
The Digestion of Feed
The Digestive System ................................................................. 86
Carbohydrate Digestion ............................................................. 89
Lipid Digestion ........................................................................... 90
Protein Digestion ........................................................................ 91
Basic Nutrition
The Role of Energy in Dairy Cattle Nutrition ............................. 92
The Role of Fibre in Dairy Cattle Nutrition ............................... 93
The Role of Protein in Dairy Cattle Nutrition ............................ 94
The Role of Minerals in Dairy Cattle Nutrition .......................... 96
The Role of Vitamins in Dairy Cattle Nutrition .......................... 99
The Role of Water in Dairy Cattle Nutrition ............................ 101
Feeding Management
Calves - Birth to Breeding
Growth Targets ................................................................... 102
Monitoring Heifer Growth .................................................. 103
Colostrum ........................................................................... 104
Feeding Milk to Calves ....................................................... 105
Milk Replacers .................................................................... 107
Nutrient Requirements of Calves Fed Milk
or Milk Replacer Only ................................................... 109
Calf Starter .......................................................................... 110
Conventional versus ‘Accelerated’
Calf Feeding Programs .................................................. 111
Nutrient Requirements of Calves Fed Milk
or Milk Replacer and Starter ......................................... 112
Feeding Hay to Calves ........................................................ 113
Weaning .............................................................................. 115
Feeding Calves from Weaning to Breeding ....................... 116
Nutrient Requirements of Weaned Calves ......................... 117
Bred Heifers
Feeding Bred Heifers .......................................................... 119
Nutrient Requirements of Springing Heifers ...................... 121
Lactating Cows
Feeding Lactating Cows ..................................................... 122
Total Mixed Rations ............................................................. 124
Lactation Curves ................................................................ 126
Dry Matter Intake by Lactating Cows................................. 127
Condition Score Targets ..................................................... 128
Nutrient Requirements of Early Lactation Cows ............... 130
Nutrient Requirements of Mid LactationCows .................. 131
Dry Cows
Feeding Dry Cows .............................................................. 132
Nutrient Requirements of Dry Cows .................................. 133
Nutrition & Health
Effects of Nutrition on Health .................................................. 134
Nutritional & Metabolic Disorders
Rumen Acidosis .................................................................. 136
Bloat .................................................................................... 137
Displaced Abomasum ........................................................ 138
Fat Cow Syndrome ............................................................. 140
Fatty Liver Syndrome ......................................................... 141
Grass Tetany ........................................................................ 142
Ketosis ................................................................................. 143
Milk Fever ........................................................................... 144
Retained Placenta ............................................................... 146
Udder Edema ..................................................................... 147
Ration Formulation ......................................................... 148
Typical Analyses of Western Canadian Feeds ................. 149
Glossary of Terms ............................................................. 153
Index ................................................................................ 169
Feeds & Feeding 19
GC
GREEN
CERTIFICATE
CURRICULUM
Feed Analysis &
Interpretation
DPP
TOC
DPP
INDEX
The purpose of feed analysis is to estimate its nutritional value
for livestock. The methods of analysis and the calculations
applied to those analyses have their limitations and, therefore,
the results must be interpreted with an understanding of
these limitations.
A typical feed analysis report is shown on the next page. Each
line in the results is linked to an explanation of the method
used to derive the values given.
Typical analyses of feedstuffs used in western Canadian dairy
diets are presented in Appendix A.
Lab Number: 99377
Feed Type: ALFALFA SILAGE
Producer: ROCKY VIEW
Sample Description: August 02 Haylage
Workorder Number: 563458
Client Feed Code:
Sender Sample Number: 02-2643
Client:
Address:
Phone:
Fax:
UNIFEED
5902 - 48 AVENUE
OLDS, AB
T4H 1V1
Moisture %
Dry Matter %
Crude Protein %
Heat Damaged Protein %
Available Protein %
Soluble Protein %
Percent Soluble %
Digestible Protein (est) %
Acid Detergent Fiber %
Neutral Detergent Fiber %
Ether Extract %
Net Energy for Lactation Mcal/kg
Net Energy for Maintenance Mcal/kg
Net Energy for Gain Mcal/kg
Digestible Energy Mcal/kg
Non-Structural Carbohydrates %
Relative Feed Value (RFV)
Phosphorus (P) %
Calcium (Ca) %
Potassium (K) %
Magnesium (Mg) %
Sodium (Na) %
Copper (Cu) ppm
Iron (Fe) ppm
Manganese (mn) ppm
Molybdenum (Mo) ppm
Zinc (Zn) ppm
Selenium (Se) ppm
Sulfur (S) %
Nitrate (as KNO3) %
Chloride (Cl) %
Analyst
Date Processed: Sep 14, 2002
Note:
As Received
64.5
35.5
6.3
0.4
6.3
3.4
4.3
12.0
16.0
0.9
0.49
0.49
0.24
0.9
9.0
0.08
0.58
0.76
0.12
0.04
2.4
126
14
0.8
10
0.08
0.1
0.18
0.23
Approved
403-556-3395
403-556-8660
Dry Result
0.0
100.0
17.7
1.0
17.7
9.6
54
12.2
33.9
45.0
2.5
1.35
1.39
0.68
2.6
25.3
129
0.23
1.64
2.15
0.33
0.10
6.7
355
39
2.3
27
0.23
0.30
0.50
0.65
Feeds & Feeding 21
GC
GREEN
CERTIFICATE
CURRICULUM
NIR or Wet Chemistry?
DPP
TOC
DPP
INDEX
The standard methods of feed analysis described here are
primarily based on assays requiring the use of chemical
reagents—they are ‘wet chemistry’ methods. Over the past 20
years, an increasing number of analyses have been performed
by Near Infrared Reflectance Spectroscopy (NIR or NIRS) which is
an indirect method of estimating feed composition.
In NIR, a finely ground sample of feed is exposed to a range of
wavelengths in the near infrared range of the visible light
spectrum. Characteristics of the organic components of the
feed sample cause some of that light to be reflected. For
example, the unique bond between carbon and nitrogen in
proteins reflects light at very specific wavelengths. By
detecting the amount of light reflected at a large number of
wavelengths, the NIR spectrometer can determine the
sample’s chemical composition.
To produce analysis results that have meaning for animal
nutrition, the NIR method has to be calibrated using samples
whose composition has been determined by wet chemistry.
For example, to determine Neutral Detergent Fibre (NDF)
levels in alfalfa haylages, NIR has to be calibrated against a set
of alfalfa haylage samples with predetermined and widely
varying NDF levels. This makes it possible to associate a
particular NIR reflectance spectrum with a specific NDF
concentration in that type of forage.
When properly used, NIR can be an accurate and economical
method for analysing feeds. Improperly used, NIR can yield
erroneous results having no value. For example, the analysis of
red clover silage using an alfalfa calibration is likely to yield
incorrect results. And, since NIR measures characteristics of the
organic constituents in feed, it is a stretch to assume that
mineral levels measured by NIR are reliable.
Feeds & Feeding 22
GC
GREEN
CERTIFICATE
CURRICULUM
Dry Matter and
Moisture
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
The Dry Matter (DM) content of a feed is determined by
weighing a sample before and after complete drying, usually
at 70-80°C. For example, if a sample of silage weighs 100
grams before drying and 40 grams after, it contains 40% DM.
Since most of the weight lost during drying is water, the
original sample contained approximately 60% moisture.
Drying may also evaporate other volatile compounds which
may have nutritional value, particularly from silages.
DM and moisture content of feeds can be measured
on-farm using a Koster Crop Tester or microwave oven.
Most feed labs report analysis results on both a wet
and a dry basis. The wet basis may be referred to by
the terms: as is, as fed or as received. The 100% dry
basis is usually referred to as: dry, DM, dry basis or dry
result. You can convert from one basis to the other
using the following formulas:
As Fed basis = DM basis x (Dry Matter % / 100)
DM basis =
The Koster Crop Tester consists of a heater/fan drying
unit, a screen-bottomed
sample container and a
simple spring scale.
As Fed basis
(Dry Matter % / 100)
When diets are formulated for dairy cattle, analysis
results quoted on a DM basis are used. Forage quality results
are also normally quoted on this basis. However, analysis
guarantees on manufactured feeds are stated on an ‘as fed’
basis. If no Moisture % or Dry Matter % is given for the
product, it can be assume to be 90% dry matter. Before using
manufactured feeds in a ration formulation, their guaranteed
analysis levels must be converted to the DM basis using the
second formula above. For example, a 16% Dairy Ration will
contain 17.8% crude protein [16 / (90/100)] on a DM basis.
Feeds & Feeding 23
GC
GREEN
CERTIFICATE
CURRICULUM
Microwave Oven Dry
Matter Estimation
DPP
TOC
DPP
INDEX
Forage dry matter levels can be accurately estimated using an
inexpensive microwave oven and a $70-80 electronic postal
scale. Mechanical postal scales are generally not accurate
enough to indicate gram differences in dry weights.
Here’s how it’s done :
1 Weigh a microwave-safe container large enough to hold
100-200 grams of wet forage (a paper bag is a good
choice). Record the weight of the container (WC) or, if your
scale has a tare adjustment, set the scale at zero (WC = 0).
2 Weigh 100-200 grams of wet forage into the container
(WW). The larger the sample, the more accurate your
determination can be.
idea: put a javascript
calculator here
3 Place a drinking glass or glass jar containing 250 ml of
water in the back corner of the oven. The water serves as a
‘ballast’ to absorb excess energy, preventing ignition of the
sample. If your sample does ignite, turn off the oven,
unplug the power but don’t open the door until the
sample has burned completely.
4 Heat the forage sample at 80-90% of maximum power for 5
minutes. Re-weigh and record the weight.
5 Repeat step 4 until the weight is less than 5 grams lower
than the previous weight.
6 Heat the sample at 30-40% of maximum power for 1
minute. Re-weigh and record the weight.
7 Repeat step 6 until the weight is less than 1 gram lower
than the previous weight. This is the dry weight (WD).
8 Calculate Dry Matter (DM) % as follows :
DM% = WD - WC x 100
WW - WC
Feeds & Feeding 24
GC
GREEN
CERTIFICATE
CURRICULUM
Acid Detergent Fibre
DE (Mcal/kg DM)
3.0
DE = 3.575 - 0.0238 x ADF
A
2.8
2.6
2.4
25
R2 = 0.5437
B
30
35
40
Acid Detergent Fibre %
This graph shows the relationship between acid detergent
fibre (ADF) and Digestible
Energy (DE) for a set of
Alberta grass forage samples.
In this example, ADF value
accounted for only 54% of the
variation in DE values.
DPP
INDEX
For the determination of Acid Detergent Fibre (ADF), feed
samples are boiled in a solution containing sulfuric acid and
the detergent, Cetyl Trimethyl Ammonium Bromide.
Hemicelluloses and cell wall proteins are dissolved, with the
residue containing cellulose, lignin, lignified nitrogen, cutin,
silica and some pectins. ADF% is simply the weight of the
residue expressed as a percentage of the original sample.
Go To Typical Analyses of
Western Canadian Feeds
3.2
DPP
TOC
45
It is assumed that the digestibility of a feed is
inversely proportional to its ADF content and
therefore, ADF is used to estimate feed energy
values (digestibility). However, the relationship
between ADF and digestibility is often poor, ADF
usually accounting for less than 65% of the
variance in digestibility (r2< 0.65).
Feeds & Feeding 25
GC
GREEN
CERTIFICATE
CURRICULUM
Neutral Detergent
Fibre
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
For the determination of Neutral Detergent Fibre (NDF), feed
samples are boiled in a solution containing Sodium Lauryl
Sulfate. This detergent extracts lipids, sugars, organic acids
and other water soluble components as well as pectin, Nonprotein Nitrogen (NPN) compounds, soluble protein and
some of the silica and tannin. NDF is the insoluble residue
made up of cellulose, hemicellulose, lignin, lignified
nitrogen, some protein, minerals and cutin. NDF% is the
weight of the residue expressed as a percentage of the original
sample.
Since it provides the most complete measure of cell wall
components, NDF is used to balance fibre requirements in the
formulation of dairy diets. A common recommendation is that
75% of the total NDF requirement for lactating cows should be
provided as forage. Other schemes, including the Cornell Net
Carbohydrate and Protein System, attempt to assign an
effective NDF value to each feed, based on both its chemical
NDF content and the ability of that NDF to provoke chewing
and salivation.
Feeds & Feeding 26
GC
GREEN
CERTIFICATE
CURRICULUM
Non-Fibre
Carbohydrates
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Non-fibre Carbohydrates (NFC) represent feed carbohydrates,
including starch, pectin and sugars, which are more rapidly
degradable in the rumen relative to the cell wall carbohydrates
measured as Neutral Detergent Fibre (NDF). NFC content is
not measured directly, but is calculated by difference:
NFC = 100 - Crude Protein - Crude Fat - NDF - Ash
A variation on NFC is Non-structural Carbohydrates (NSC), used
in the Cornell Net Carbohydrate and Protein System, where:
NSC = 100 - Crude Protein - Crude Fat
- (NDF - Neutral Detergent Insoluble Protein) - Ash
In the NSC equation, the Crude Protein associated with the
NDF fraction is subtracted so that it is not accounted for twice;
in both CP and NDF fractions.
Feeds & Feeding 27
GC
GREEN
CERTIFICATE
CURRICULUM
Energy Estimates
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Most feed labs calculate forage energy estimates from Acid
Detergent Fibre (ADF) concentrations. Equations vary from
lab to lab, so it is important to determine whether differences
in reported energy values between labs is due to different ADF
values or different equations or both. Typical equations used
to calculate Net Energy for Lactation (NEL) are as follows (see
table on following page):
• for forages which are greater than 75% legume:
NEL (Mcal/kg) = 2.302 - 0.0262 x ADF %
• for forages which are a mixture of grasses and legumes, with
neither making up greater than 75% of the total:
NEL (Mcal/kg) = 2.398 - 0.028 x ADF %
• for forages which are greater than 75% grass:
NEL (Mcal/kg) = 2.392 - 0.0273 x ADF %
• for small grain (e.g. Barley) silages and greenfeeds:
NEL (Mcal/kg) = 1.75 - 0.0076 x ADF %
• for Corn silage:
NEL (Mcal/kg) = 2.302 - 0.0273 x ADF %
The following equations can be used to convert between
energy units:
Total Digestible Nutrients (TDN, %) = [(NEL (Mcal/kg) + 0.12) / 0.0245]
Digestible Energy (DE, Mcal/kg) = TDN % x 0.04409
Metabolizable Energy (ME, Mcal/kg) = 1.01 x DE (Mcal/kg) - 0.45
Net Energy for Maintenance (NEM, Mcal/kg)
= 1.37 x ME - 0.138 x ME2 + 0.0105 x ME3 - 1.12
Net Energy for Gain (NEG, Mcal/kg)
= 1.42 x ME - 0.174 x ME2 + 0.0122 x ME3 - 1.65
... continued
Energy Estimates
(continued)
Appendix A includes a table which can be used to convert
energy levels quoted as NEL to NEM, NEG and TDN.
Estimates of the energy contributed by concentrate feeds are
most commonly based on values published in tables of feed
composition. An alternative method of estimating energy
values for all feeds was proposed in the 2001 edition of
Nutrient Requirements of Dairy Cattle, published by the US
National Research Council. This method is based on
calculating TDN from estimates of the true digestibility of feed
fractions.
Energy values calculated from
forage acid detergent fibre
concentrations using the
equations on the previous
page.
ADF
%
TDN
%
DE
ME
NEM
NEG
NEL
--------------------- Mcal/kg -------------------
Forages >75% Legume
25
72.1
3.18
2.76
30
66.8
2.94
2.52
35
61.4
2.71
2.29
40
56.08
2.47
2.05
Mixed Grass/Legume Forages
25
74.2
3.27
2.85
30
68.5
3.02
2.60
35
62.8
2.77
2.35
40
57.06
2.52
2.09
Forages >75% Grass
25
74.7
3.29
2.88
30
69.1
3.05
2.63
35
63.5
2.80
2.38
40
58.0
2.56
2.13
Small Grain Forages
25
68.6
3.02
2.60
30
67.0
2.95
2.53
35
65.5
2.89
2.47
40
63.9
2.82
2.40
Corn Silage
25
71.0
3.13
2.71
30
65.4
2.88
2.46
35
59.9
2.64
2.22
40
54.3
2.39
1.97
1.83
1.63
1.42
1.20
1.20
1.02
0.83
0.63
1.65
1.52
1.39
1.25
1.91
1.69
1.47
1.24
1.27
1.08
0.88
0.67
1.70
1.56
1.42
1.28
1.93
1.72
1.50
1.27
1.28
1.10
0.91
0.70
1.71
1.57
1.44
1.30
1.70
1.64
1.58
1.52
1.08
1.03
0.98
0.92
1.56
1.52
1.48
1.45
1.79
1.57
1.35
1.12
1.16
0.97
0.77
0.56
1.62
1.48
1.35
1.21
Feeds & Feeding 29
GC
GREEN
CERTIFICATE
CURRICULUM
Relative Feed Value
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Relative Feed Value (RFV) is an index of forage quality
calculated from Acid Detergent Fibre (ADF) % and Neutral
Detergent Fibre (NDF) % using the following formula:
RFV =
[(88.9 - (0.78 x ADF %)) x (120 / NDF %)]
1.29
Notice that RFV does not account for the Crude Protein % of
the forage. It is based only on fibre levels and is, therefore, an
index of forage digestibility and potential intake.
Feeds & Feeding 30
GC
GREEN
CERTIFICATE
CURRICULUM
Relative Feed Quality
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Relative Feed Quality (RFQ) is a new variation on Relative
Feed Value (RFV), designed to account for differences in
Neutral Detergent Fibre (NDF) digestibility between forages.
Two forages with the same levels of Acid Detergent Fibre
(ADF) and NDF will have the same calculated Relative Feed
Values. However, if the NDF digestibility of one of these
forages is higher , it will have a higher Relative Feed Quality.
NDF digestibility values for haylage (for example) can range
from less than 30% to greater than 60%.
RFQ is a more accurate index of the value of a forage for milk
production. Studies at Michigan State University showed that
a 1 percentage unit increase in NDF digestibility was
associated with a 0.17 kg increase in dry matter intake leading
to a 0.23 kg increase in daily 4% fat-corrected milk production.
The base equation used to calculate RFQ is:
RFQ = (DMI, % of body weight) x (TDN, % of DM) / 1.23
Dry Matter Intake (DMI) is estimated using one of two
equations—one for forages containing legumes, a second for
grasses. TDN (Total Digestible Nutrients) is calculated
according to equations in the 2001 edition of Nutrient
Requirements of Dairy Cattle, published by the US National
Research Council.
Feeds & Feeding 31
GC
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CURRICULUM
Crude Protein
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
The Crude Protein (CP) concentration in feeds is determined
using the Kjeldahl procedure. A dried sample is first digested
in concentrated sulfuric acid, which converts most of the
nitrogen (N) to ammonium sulfate (N present as nitrate is only
partially converted). This mixture is cooled, diluted with water
and neutralized using sodium hydroxide, resulting in the
dissociation of ammonium sulphate. Distillation drives off
ammonia and the distillate is titrated with acid to determine
its ammonium concentration, from which the N level in the
original sample is calculated.
Since most feed proteins contain about 16% N, CP% is
estimated by multiplying the N concentration in the feed by
6.25 - the inverse of 16% (1 ÷ 0.16 = 6.25). However, some
portion of the N in most feeds is found as Non-protein
Nitrogen (NPN) and, therefore, the value calculated by
multiplying N x 6.25 is referred to as Crude rather than true
protein.
Feeds & Feeding 32
GC
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Non-Protein Nitrogen
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Crude Protein (CP) is composed of two nitrogen-containing
feed fractions: True protein and Non-protein Nitrogen (NPN). To
separate these two fractions, True Protein is precipitated out of
solution using either tungstic acid or trichloroacetic acid (TCA).
The NPN left in solution is measured using the Kjeldahl
procedure as described for the determination of CP.
NPN, including compounds such as urea, ammonium salts,
amino acids, small peptides and nucleic acids, represents the
fraction of Crude Protein most rapidly degradable in the
rumen.
Feeds & Feeding 33
GC
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Soluble Protein
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
The Soluble Protein (SP) content of a feed is estimated by
mixing a sample in borate-phosphate buffer solution. Crude
Protein (CP) which is soluble in the buffer is measured using
the Kjeldahl procedure.
SP estimates the amount of CP which will readily dissolve
when a feed enters the rumen. It is assumed that this fraction
represents CP (both true protein and non-protein nitrogen)
which is rapidly degraded by rumen microbes. The CP of most
forages is 40-50% soluble. Higher SP levels are often found in
silages which are put up very wet (less than 30% dry matter).
When this is the case, the Rumen Undegradable Protein
(RUP) value of the forage should be discounted.
Feeds & Feeding 34
GC
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CURRICULUM
Acid Detergent
Insoluble Nitrogen
Go To Typical Analyses of
Western Canadian Feeds
Photo of heat damaged
haylage.
DPP
TOC
DPP
INDEX
When silage is put up too dry (greater than 50% dry matter) or
hay too wet (less than 85% dry matter), excessive heating may
cause some of the protein in the crop to become irreversibly
bound to lignin. Heating during the processing of feeds (e.g.
pelleting) can have the same effect.
The severity of heat damage is estimated in the feed lab by
measuring the amount of nitrogen (N) associated with the
Acid Detergent Fibre (ADF) residue. Depending on the feed
lab, this fraction may be reported as Acid Detergent Insoluble
Nitrogen (ADIN), Acid Detergent Insoluble Protein (ADIP), Acid
Detergent Fibre Nitrogen (ADF-N), Acid Detergent Fibre Protein
(ADF-P) or Heat-damaged Protein, expressed as a percentage of
either total N, total crude protein or feed dry matter. Nitrogen
values are multiplied by 6.25 to convert to Protein values.
In most feeds, 3-8% of total CP will be associated with the ADF
residue, even in the complete absence of heating. Therefore,
most feed labs do not discount the total CP value for heat
damage unless ADIN values are excessive. Others assume that
a fixed proportion (e.g. 70%) of ADIN is unavailable.
Discounted CP (Total CP - ADIP or Total CP - excess ADIP)
values are often reported as Adjusted Crude Protein (ACP).
Feeds & Feeding 35
GC
GREEN
CERTIFICATE
CURRICULUM
Neutral Detergent
Insoluble Nitrogen
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Neutral Detergent Insoluble Nitrogen (NDIN) represents
nitrogen associated with the cell wall, measured by subjecting
the Neutral Detergent Fibre (NDF) residue to the Kjeldahl
procedure. Neutral Detergent Insoluble Protein (NDIP) is NDIN x
6.25.
A fraction of NDIP will be both degradable by rumen microbes
and digestible in the small intestine. A second fraction will be
completely indigestible. In the Cornell Net Carbohydrate
and Protein System, it is assumed that the completely
indigestible fraction is estimated as Acid Detergent Insoluble
Nitrogen x 6.25. The degradable/digestible fraction is,
therefore, calculated by difference: [(NDIN - ADIN) x 6.25].
Feeds & Feeding 36
GC
GREEN
CERTIFICATE
CURRICULUM
Rumen Degradable
Protein
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Rumen Degradable Protein (RDP) is the fraction of Crude
Protein (CP) consumed which is broken down by rumen
microbes. In the 1989 edition of Nutrient Requirements of Dairy
Cattle, RDP was referred to as Degradable Intake Protein (DIP).
The degradability of the protein in any particular diet or feed
ingredient is dependent upon both the feed itself and the
animal to which it is fed. When feed intake is low (e.g., dry
cow), passage of feed through the rumen is slower and RDP
may be higher because time of exposure to microbial
degradation is increased. Conversely, high intakes (e.g., peak
lactation cow) accompanied by high feed passage rates result
in lower RDP values.
RDP is estimated by measuring the disappearance of CP from
feed samples incubated in porous nylon bags in the rumen of
a fistulated animal such as the one shown on the left. The
procedure is labourious and expensive, limiting its use to
research facilities. Results obtained with this method have
been quite variable both within and between laboratories.
A much simpler benchtop method has been proposed, in
which feed samples are incubated with a mixture of proteindegrading enzymes extracted from the rumen. Although
several commercial labs offer RDP analysis using this method,
lack of standardization of both protocols and enzymes makes
it difficult to place confidence in results.
Soluble Protein and Non-protein Nitrogen (NPN) are crude
protein fractions considered to be rapidly and completely
degraded in the rumen. Since these two fractions can be
readily measured in the feed lab, they have been used as
indicators of feed protein degradability.
Feeds & Feeding 37
GC
GREEN
CERTIFICATE
CURRICULUM
Crude Fat
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Crude Fat content is estimated by extracting a ground feed
sample with diethyl ether. The ether soluble components
(ether extract) may include true fats and oils, fatty acid esters,
compound lipids and fat-soluble vitamins or provitamins
such as the carotenoids, all of which may have nutritional
value. However, ether extract may also contain significant
concentrations of indigestible waxes, resins and essential oils.
The measurement of Crude Fat was an important part of the
historical method of proximate analysis where it represented
feed components with a caloric value 2.25 times that of
carbohydrate or protein. Today it is used to estimate fat
content of a feed for formulation of total dietary fat level and
for calculation of Non-fibre Carbohydrate (NFC) by difference:
NFC = 100 - Crude Protein - Crude Fat - NDF - Ash
Feeds & Feeding 38
GC
GREEN
CERTIFICATE
CURRICULUM
Minerals
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
The total mineral content of a feed sample is estimated by
burning off the organic matter. The amount of ash remaining
is mainly used in other calculations, such as those for Nonfibre Carbohydrates and Non-structural Carbohydrates.
Individual minerals are measured using a variety of chemical
methods, including:
• colorimetry;
• atomic absorption spectrophotometry;
• inductively coupled plasma spectrophotometry (ICP).
Often, the levels of Calcium, Phosphorus, Sodium and
Potassium reported by feed analysis labs are estimated by NIR
(Near Infrared Reflectance Spectroscopy). The accuracy of
mineral analysis results using this method are questionable.
Feeds & Feeding 39
GC
GREEN
CERTIFICATE
CURRICULUM
Vitamins
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Vitamin concentrations in feed are measured using a variety of
costly chemical and spectral methods. Few labs offer these
analyses as part of their standard feed analysis packages.
Because of the expense of vitamin analyses and the
uncertainty involved in estimating vitamin levels, it is usually
assumed that basal dietary ingredients contribute little or
nothing to the vitamin requirements of livestock.
Supplementation in the form of injection or feed premix is
used to assure that the animals receive the vitamins they
require.
Feeds & Feeding 40
GC
GREEN
CERTIFICATE
CURRICULUM
Silage pH
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
The degree of acidity in silage is measured as pH. Pure distilled
water with no dissolved gases or other ions (charged atoms)
has a pH of 7. Strong acid will have a pH of 2 to 3; a strong
base will have a pH of 11 to 12. Before fermentation begins,
the pH of wet forage is usually in the 6.0-6.5 range. As bacteria
in the forage ferment soluble sugars to produce acid, pH falls.
Ideally, silage will have a pH in the 3.8-5.0 range. At this level of
acidity, the silage will not be subject to the growth of moulds
which can impair its feed quality.
Corn and small cereal silages generally reach a low pH with
little difficulty thanks to their high sugar content. Legume
silages seldom reach pH levels below 5.0 because of their low
sugar content and high buffering capacity (buffers are
chemicals that resist pH changes). Grasses have intermediate
levels of both sugar and buffers, usually producing silages with
pH levels in the upper end of the ideal range.
Paper pH test strips can be
used to estimate silage pH.
Silage pH can be measured relatively easily in the field using
either a pH test strip or a portable pH metre. A 100 gram
sample of silage is thoroughly mixed with 100 millilitres of
water and the liquid is poured into a test vial. The pH metre or
test strip is simply dipped into the liquid sample to determine
the pH of the silage.
Feeds & Feeding 41
GC
GREEN
CERTIFICATE
CURRICULUM
Bulk Density
Average
Diameter
Height
Go To Typical Analyses of
Western Canadian Feeds
48
37
49
48
51
DPP
INDEX
Bulk density is the weight of a standard volume of grain. In the
past, this was measured as bushel weight but, since adoption
of the metric system, kilograms per hectolitre (kg/hL) is used
as the standard unit of measure. Although bulk density is a
generally accepted measure of grain quality, its relationship to
nutritional value is not clear. Most assume that grain of higher
density is worth more as a dietary ingredient.
To determine bulk density you will need a small pail, a ruler
and a scale. The method is as follows:
1 Determine the empty weight of the pail in kg (WE).
lbs per kgs per
bushel hectolitre
Barley
Oats
Rye
Triticale
Wheat
DPP
TOC
62
48
63
62
65
Bulk density standards for
western Canadian feed
grains.
2 Measure the average diameter and height of the pail in
centimetres and calculate its volume in litres using this
formula:
height (cm) x (avg diameter (cm) ÷ 2)2
volume (litres) =
1000 cubic centimetres per litre
For example, if the average diameter of the pail is 30 cm
and the height is 20 cm, its volume is: 20 x (30 ÷ 2)2 = 4500
cubic centimetres ÷ 1000 = 4.5 litres
3 Fill the pail with grain. Use the ruler to even off the top of
the grain with the top of the pail.
4 Determine the kg weight of the pail filled with grain (WF).
5 Calculate bulk density using the following formula:
Bulk Density (kg/hL) = WF (kg) - WE (kg) x 100 litres per hL
volume (litres)
For example, if the grain weighs 3 kg, the bulk density is
3 kg ÷ 4.5 litres x 100 litres per hL = 66.7 kg/hL.
6 Compare your measured value with the reference values in
the table on the left.
Feeds & Feeding 42
GC
GREEN
CERTIFICATE
CURRICULUM
Particle Size
The Penn State Forage
Particle Separator
DPP
TOC
DPP
INDEX
Fibre has a particularly important role in ruminant nutrition.
It is important to distinguish between chemical fibre and
physical fibre. Chemical fibre is measured in the feed lab as
Acid Detergent Fibre (ADF) and Neutral Detergent Fibre
(NDF). Physical fibre, or structured roughage, stimulates
chewing and salivation which keeps the rumen functioning
normally. Since long particles require more chewing than
short particles, it is useful to estimate the distribution of
particle sizes in forages and complete diets.
Forage particle size distributions can be estimated
using the Penn State Forage Particle Separator shown
on the left. The separator consists of three screens
with hole sizes decreasing from top to bottom plus a
bottom pan. A sample of forage or total mixed ration
(TMR) is placed on the top screen, the separator is
shaken and the amount of forage remaining in each of
the 4 sections is weighed.
Recommendations for different forage types vary widely.
Guidelines for TMRs fed to high producing dairy cows are:
• 2 to 8 percent of the particles in the upper sieve;
• 30 to 50 percent in the middle and lower sieves, and;
• no more than 20 percent in the bottom pan.
Feeds & Feeding 43
GC
GREEN
CERTIFICATE
CURRICULUM
Processing Index
DPP
TOC
DPP
INDEX
To be efficiently digested by dairy cattle, feed grains need to
be processed by either grinding or rolling. This is because the
fibrous hull of the whole grain kernel limits access to its
starchy core by both microbes in the rumen and digestive
enzymes in the lower digestive tract. Conversely, Barley which
is finely processed is rapidly digested in the rumen—an
advantage in terms of maximizing microbial protein sythesis
but a disadvantage due to a higher risk of rumen acidosis.
Processing index (PI) is a measure of the degree of grain
processing. As grain is rolled more finely, its bulk density
decreases. PI is the bulk density of grain after processing
expressed as a percentage of its bulk density before
processing. For example, if a sample of Barley had a bulk
density of 60 kg/hL before rolling and 42 kg/hL after, we would
assign the rolled grain a PI of 70% (42/60 x 100%). To put PI
values into perspective, steam-rolled Barley samples obtained
from 10 southern Alberta feedmills had PI values which varied
from 63 to 79%, with most in the 65 to 70% range. In contrast,
dry- or temper-rolled samples from 9 feedlots had PI values
between 72 and 91%.
In a lactating cow study conducted in southern Alberta, Barley
rolled to a PI of 64% gave the best results in terms of
maximum production with limited risk of acidosis, in diets
formulated to contain 22% NDF from forage. Had lower forage
diets been fed, optimum PI would likely have been higher.
Conversely, a diet containing more forage might have allowed
the feeding of Barley with a lower PI without increasing the
risk of acidosis.
Feeds & Feeding 44
GC
GREEN
CERTIFICATE
CURRICULUM
Perennial Grasses
Go To Typical Analyses of
Western Canadian Feeds
100
80
% leaves
70
60
% NDF in stems
50
40
DPP
INDEX
Perennial grasses are fed to dairy animals in the form of
pasture, green chop (cut and carried, fed fresh), hay (also
referred to as green feed) and silage. When ensiled, perennial
grasses and legumes are often called hay-crop silages to
differentiate them from grain-crop (cereal) silages.
Smooth Bromegrass
90
DPP
TOC
The intake potential and nutritional quality of
grasses are largely dependent on their stage of
maturity. As the grass plant matures, the stem
elongates, the proportion of leaf to stem
decreases, fibre content increases and Crude
Protein declines. These relationships are
shown in the graphs on the left, where
bromegrass is used as an example.
% NDF in leaves
30
Perennial grasses commonly used in western
Canadian dairy diets include:
20
% CP in leaves
Bromegrass: there are two types of
bromegrass—a southern type and a northern
0
May June
July
Aug
Sept
Oct
type. In western Canada, the northern type is
Immature Full bloom Mature
Dormant
more vigorous and has higher seed yields than
Early bloom Milk stage Overripe
the southern type. It is tolerant of drought and
extreme temperatures and can be grown
Changes in composition of
alone or mixed with other grasses and legumes.
smooth bromegrass as plants
Bromegrass is the most commonly used companion to
mature.
alfalfa in mixtures grown on dryland.
10
% CP
in stems
Orchardgrass is used for pasture, silage and hay. It has a deep,
competitive root system and can interfere with nutrient
uptake in legumes so the two should not be grown
together, especially when heavily fertilized with nitrogen.
...continued
Perennial Grasses
(continued)
Perennial Ryegrass is rarely grown in the prairie provinces
although it is very common in south coastal British
Columbia. A short-lived bunch grass with a shallow root
system, it is very palatable and nutritious when harvested
at the correct maturity.
Reed Canarygrass is particularly tolerant of low, poorly drained
areas. Canarygrass is palatable to cattle as long as it is not
allowed to become too mature as it becomes coarse with
age. It is often used to stabilize the banks of waterways
because of its ability to develop a dense sod.
Tall Fescue can grow even on the poorest of soils. It is tolerant
of both acidic and alkaline soils and, although it has a low
moisture requirement, tall fescue does especially well
under moist conditions. It can also be used to control soil
erosion.
Timothy is used for both pasture and hay; it grows well with
legumes; and is easy to harvest. Overmature timothy is
very fibrous, limiting intake.
Wheatgrass: there are several different types of wheatgrass:
crested, intermediate, pubescent, slender, streambank and
tall. This plant is persistent, drought resistant, and it can be
found throughout the Canadian Prairies.
Smooth Bromegrass
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
Orchardgrass
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
Perennial Ryegrass
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
Tall Fescue
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
Timothy
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
Wheatgrass
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
Feeds & Feeding 52
GC
GREEN
CERTIFICATE
CURRICULUM
Annual Grasses
Go To Typical Analyses of
Western Canadian Feeds
Annual (Italian) ryegrass,
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
DPP
TOC
DPP
INDEX
Other than the grain crop forages, annual grasses are not
commonly used in western Canadian dairy diets. The one
exception is Annual (Italian) Ryegrass, a quick growing, highyielding species which establishes easily. Although
most commonly used for grazing, Italian Ryegrass
makes good quality hay or silage when harvested at
the correct stage of maturity. Changes in
composition with advancing maturity are similar to
those for perennial grasses.
Feeds & Feeding 53
GC
GREEN
CERTIFICATE
CURRICULUM
Grain Crop Forages
Go To Typical Analyses of
Western Canadian Feeds
DPP
TOC
DPP
INDEX
Grain crops (members of the grass family Gramineae)
including Barley, Corn, Oats, Rye, Triticale and Wheat are
common forage sources in western Canadian dairy diets—
primarily fed as silage.
Barley grows best in well drained, fertile soils. This plant has
also adapted to growth in sandy soils. The disadvantage to
using Barley is the presence of awns on the stems which
are spiky and decrease palatability.
Corn silage is highly palatable and a good source of digestible
energy (due to grain content). It is, however, low in
digestible protein.
Rye is well suited for pasture because of its high productivity.
A disadvantage of using Rye as pasture is that it quickly
becomes unpalatable as it matures.
Oats can be grazed or stored as hay (greenfeed) or silage.
Particular varieties (e.g., Foothills) have been bred for use as
high quality forages.
Triticale is the result of a cross between Wheat and Rye. It has
the potential to be higher yielding than Barley but many
attempts to feed Triticale silage to lactating cows have
been disapppointing due to low intakes.
Wheat can be used for pasture, silage or hay. It is a quality crop
that is palatable, high in protein and energy and low in
fibre.
As pasture, these crops can be grazed during winter months
(in climates where weather permits) and into early spring
without reducing the harvest yields of the grain. When
ensiling Barley, Triticale, Rye or Wheat the moisture content
should be 62-68 % to avoid excessive air in the stems and a
stronger concentration of butyric acid in the silage.
Feeds & Feeding 54
GC
GREEN
CERTIFICATE
CURRICULUM
Legume Forages
Go To Typical Analyses of
Western Canadian Feeds
100
90
% leaves
80
% NDF in stems
60
50
% NDF in leaves
40
30
% CP in leaves
20
10
DPP
INDEX
Legume forages are primarily fed to dairy animals as hay and
silage. They are seldom offered as pasture or as fresh-cut
forage because of their potential to cause bloat. When ensiled,
perennial grasses and legumes are often called hay-crop
silages to differentiate them from grain-crop (cereal) silages.
Ladak Alfalfa
70
DPP
TOC
Like grasses, the intake potential and
nutritional quality of legumes are largely
dependent on their stage of maturity. As the
plants mature, their stems elongate, the
proportion of leaf to stem decreases, fibre
content increases and Crude Proteindeclines.
These relationships are shown in the graphs on
the left, where alfalfa is used as an example. In
comparison to grasses, legumes are higher in
protein, calcium, magnesium, sulphur and
copper, but lower in manganese and zinc.
% CP in stems
The feeding of fresh legumes can pose a
significant risk of developing frothy bloat.
Due to their high fermentability and protein
content, a stable foam is produced during
Early bloom Milk stage Overripe
rumen fermentation, making it impossible for
Changes in composition of
the animal to expel excess gas by belching. As a result, gas
alfalfa as plants mature.
pressure accumulates and the animal appears to be choking.
New research in legume genetics is being directed toward
making bloat free strains to reduce the incidence of pasture
bloat in ruminants.
0
May June
July
Immature Full bloom
Aug
Sept
Oct
Mature
Dormant
continued...
Legume Forages
(continued)
Common legume crops fed to dairy cattle in western Canada
include:
Alfalfa is a perennial legume that can survive in both cold and
warm climates. Alfalfa can be used for silages, hay or
grazing. This plant can not withstand drought for long
periods of time nor can it tolerate acidic soil or a high
water table. Ingestion of this
legume can cause bloat in
ruminants. Several
companies in western
Canada produce high
quality dehydrated alfalfa
pellets and cubes for animal
feeding.
Birdsfoot Trefoil is a perennial
legume grown in temperate
to cold climates. It is tolerant
of drought and acidic soils
and can be used for hay or
pasture. Trefoil is palatable
and nutritious but also has
the potential to cause bloat.
Dehydrated alfalfa pellets.
Cicer Milkvetch is a perennial
that can grow in cold climates. It is tolerant of salty soil,
drought, flooding and acidic and alkaline conditions.
Because the crop does not cause bloat, it is commonly
used for pasture and less frequently for hay.
Red Clover is a perennial that can be grown in moist
conditions in cold, warm and acidic soils. It will, however,
not tolerate drought. There are two types of red clover:
single-cut and double-cut. Single cut varieties flower later,
are able to withstand winter better and are larger. Red
clover of both types are suitable for pasture and hay.
Alfalfa
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
Red Clover
drawing by Norman Criddle
from G.H. Clark and M.O.
Malte, Fodder and Pasture
Plants, Canada Department of
Agriculture, 1923
Feeds & Feeding 86
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GREEN
CERTIFICATE
CURRICULUM
DPP
TOC
DPP
INDEX
The Digestive System
The main parts of the cow’s digestive system are illustrated in
the diagram below. Ingested feed is chewed, mixed with saliva
and formed into a bolus before it passes down the esophagus
into the reticulum and rumen, the first two
rectum
dorsal sac of rumen
sections of the four compartment
anus
esophagus ruminant stomach. Later, boluses
duodenum
(cuds) of feed are regurgitated and
further broken down by chewing.
omasum
cecum
Whenever feed is chewed, saliva is
reticulum
secreted from salivary glands in the
abomasum
mouth. Over the course of a day, a
spiral colon
ventral sac of rumen
lactating cow will secrete more than
small intestine
200 litres of saliva which has three main
functions:
The main parts of the cow’s
• it lubricates feed as it moves down the esophagus;
digestive system.
• it provides the liquid flow which carries feed particles into
the omasum, and;
• it contains buffers which prevent rumen pH from falling too
Click here to see a video
low as microbes produce acids from feed fermentation.
about ruminant digestion
video clip used with permission
of Penn State University
STARCH
GRANULE
Electron photomicrograph of
bacteria and protozoa digesting Barley starch granules.
BACTERIA
PROTOZOA
BACTERIA
On entering the rumen, an
extremely varied population of
bacteria, protozoa and fungi
attach themselves to feed and
begin the breakdown process.
Enzymes are secreted onto the
feed and into the fluid
contents of the rumen.
Distinct microbial populations
digest specific types of feed.
For example, starch digesters
are distict from fibre digesters.
continued...
The Digestive System
(continued)
The inner lining of the rumen is not unlike pile carpet, having
innumerable small, flat projections called papillae. These
serve two primary functions. They vastly increase the area for
absorption of nutrients and they also provide attachment sites
for additional, specific populations of bacteria. For example,
the bacteria responsible for digesting urea are mainly found
attached to papillae.
Continual mixing of rumen contents is essential to efficient
fermentation. The muscular walls of the rumen and reticulum
produce waves of contraction travelling their combined
lengths at about half-minute intervals. This process, in
addition to mixing the rumen contents, facilitates both
regurgitation for further cud-chewing and eructation, which
releases gases produced by fermentation (mainly hydrogen
and methane). Under some conditions (e.g., grain overload)
these contractions may stop, resulting in rumen stasis and
placing the animal at serious risk of bloating.
After the feed has been sufficiently chewed and broken down
by microbial action, digesta enter the omasum. Flow into this
third segment of the stomach is regulated by a small opening
called the reticulo-omasal orifice which prevents large
particles from leaving the rumen. The omasum is a muscular
organ which is thought to have two main functions. The first is
the extraction of water from the digesta, yielding a product for
further digestion which has a significantly higher proportion
of dry matter. Secondly, the omasum serves as a pump,
propelling digesta from the rumen and reticulum into the
fourth segment of the stomach, the abomasum.
The ruminant abomasum is analogous to the true stomach of
monogastric animals such as humans, pigs, dogs and cats. The
digestion of proteins, fats and oils is initiated by acids and
enzymes secreted by the tissue lining the abomasum. As
these initial stages progress, the digesta pass to the
duodenum, the first segment of the small intestine. Here, bile
from the liver and gall bladder along with digestive enzymes
from the pancreas are added. Digestion and absorption of its
products progress as the digesta pass through the two lower
segments of the small intestine, the jejunum and the ileum.
The Digestive System
(continued)
Digestion is almost complete by the time the unabsorbed
digesta reach the large intestine. One of the main functions of
this part of the system is the absorption of water and minerals.
In addition, some further breakdown is carried out here by a
permanent population of microbes (bacteria and protozoa)
with some of the products being absorbed into the blood.
Food material which has escaped both enzymatic and
microbial digestion is excreted.
Feeds & Feeding 89
GC
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CERTIFICATE
CURRICULUM
Carbohydrate
Digestion
DPP
TOC
DPP
INDEX
Plant carbohydrates are the main source of energy in dairy
diets. Bacteria, protozoa and fungi in the rumen and
reticulum (rumen microbes) secrete enzymes that degrade
carbohydrates to produce volatile fatty acids (VFAs)—
primarily acetic, propionic and butyric acids. After absorption
into the bloodstream, these VFAs are used by body tissues to
synthesize protein, fat and other essential carbohydrates such
as glucose.
When diets containing large amounts of Non-structural
Carbohdrates are fed, the rate of VFA production may exceed
their rate of removal from the rumen. The resulting
accumulation of acid may cause rumen pH to decline, leading
to acidosis. Structural Carbohydrates are degraded more
slowly, resulting in a much lower rate of VFA production.
Carbohydrate degradation rates in the rumen also depend
upon the physical structure of feeds. For example,
unprocessed grain is poorly digested in the rumen because
the starch contained in the grain kernel is inaccessible to
microbial attack. Conversely, the starch in finely ground grain
is degraded very rapidly (see processing index). Although the
differences are not as great, fine chopping and aggressive
crushing of forages will also increase rates of degradation.
Non-structural Carbohdrates that escape degradation in the
rumen may be digested as they pass further down the
digestive tract either by animal enzymes secreted into the
small intestine or by microbial enzymes in the large intestine.
Mammals do not produce enzymes capable of digesting
Structural Carbohydrates. Once they pass from the rumen, the
only remaining, but limited, opportunity for further digestion
of these plant components is in the large intestine.
Feeds & Feeding 90
GC
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CERTIFICATE
CURRICULUM
Lipid Digestion
DPP
TOC
DPP
INDEX
Unless supplemental fats or oils are added, dairy diets
contain low concentrations of lipid—2-3% of dietary dry
matter is typical. Because cattle digest lipids very inefficiently,
dietary concentrations should never exceed 5-6%.
Lipid digestion in the rumen begins with cleavage of
glycerides into glycerol and free fatty acids. Glycerol is used
by rumen microbes for the synthesis of propionic acid.
Unsaturated fatty acids are hydrogenated to make them
completely saturated.
TRIGLYCERIDE
Lipids are composed of fatty acids (FA) in
free form (FFA) and as di- and triglycerides.
The FA ‘backbone’ is a long chain of 12-22
carbon atoms. A saturated FA has 2 hydrogen (H) atoms attached to each carbon (the
end carbon always has 3). When a single
pair of H atoms are missing from adjacent
carbons, the FA is monounsaturated
(MUFA); when more than one pair are
missing it is termed polyunsaturated
(PUFA). In the diagram on the right, 16:0 is
a 16-carbon (C16) FA with zero H atoms
missing—it is saturated. 18:2 is a polyunsaturated C18 FA with 2 pairs of H atoms
missing.
16:0
FFA
The saturated fatty acids then move through the digestive
tract to the small intestine where they are mixed with bile salts
and pancreatic juices. Once they have been thoroughly
emulsified, the fatty acids are absorbed into the lymph system
then slowly released into to the bloodstream for delivery to
muscles, adipose (fat) tissue, the liver and the mammary
gland for further use.
18:1
18:2
12:0
OXYGEN
CARBON
HYDROGEN
MISSING HYDROGEN
Feeds & Feeding 91
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CERTIFICATE
CURRICULUM
Protein Digestion
1
N 0
N N 7
6
17
N N
N
1
4 1
7
N
N 2
1
17
N N
N 16
N 9 13
11 N
1
12
3 N
N 16
1
1
N
N
20
18 N
N
DPP
INDEX
Crude Protein in feed is composed of both true proteins and
Non-protein Nitrogen. As illustrated in the diagram below,
true proteins are composed of long chains of amino acids.
8 N N
N 19
7
N N
N 4 11
1
DPP
TOC
13 N N
N 12
3
True proteins are composed
of long chains of amino acids.
The chain of each unique
protein (e.g., milk casein,
blood albumin) is a specific
sequence of 20 different
amino acids. Each amino acid
contains at least one atom of
nitrogen.
When feed proteins enter the rumen, those that are
degradable are broken down by microbial enzymes into
shorter chains (peptides), individual amino acids, organic acids
and ammonia. Rumen microbes use these breakdown
products to manufacture their own microbial protein. As
digestion progresses, microbes are carried out of the rumen.
In the small intestine, digestive enzymes release amino acids
from microbial protein for use by the cow. Undegradable feed
proteins pass through the rumen without being digested.
Unless they are completely resistant, they will also be digested
in the small intestine.
The blend of amino acids available to the cow is a combination
of those released by intestinal digestion of both microbial and
undegraded feed proteins. When the available blend is not
exactly what the cow requires, excess amino acids are broken
down in the liver, much of the nitrogen (N) being released as
urea and excreted.
Dietary Non-protein Nitrogen is rapidly and completely
degraded to ammonia by rumen microbial enzymes.
Feeds & Feeding 92
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The Role of Energy in
Dairy Cattle Nutrition
GROSS ENERGY IN FEED
79.8 Mcal
DIGESTIBLE ENERGY
63.8 Mcal
METABOLIZABLE
ENERGY
52.3 Mcal
NET
ENERGY
33.2 Mcal
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DPP
INDEX
When carbohydrates, fats and proteins are digested, energy
is released. While a portion of the released energy is lost, much
of the remainder is captured, to be used in the growth and
maintenance of body tissues and in the synthesis of milk.
The diagram on the left illustrates the loss and capture of
energy as feed is digested and the products of digestion are
used by the animal. Gross Energy can be estimated by
burning a sample of feed in an atmosphere of
oxygen and measuring the amount of
FECES
16 Mcal heat produced. Some of this is
unavailable to the animal because it is
indigestible, passing right through the
digestive tract to be excreted as feces. Of the
GASES
energy
released by digestion (Digestible
12 Mcal
URINE
Energy), portions are lost from both ends of
the digestive tract in the form of gas and some
is lost through urinary excretion.
HEAT OF
PRODUCTION Metabolizable Energy is available to the
19 Mcal
animal for maintenance, growth and milk
production. These processes result in the loss
of heat (Heat of Production) which, when
MAINTENANCE
ambient temperature is low, serve to keep the
10.3 Mcal
body warm. The remaining Net Energy represents
GAIN 2.6 Mcal
the amount that is actually captured by processes
GESTATION 3.1 Mcal
which require the synthesis of new organic
compounds—carbohydrates,
fats, proteins and
LACTATION
17.2 Mcal
nucleic acids. When describing feed energy values
and animal energy requirements, net energy is
Partitioning of energy in a 3rd lactation
defined by the specific process it supports: Net
cow, weighing 650 kg, producing 25 kg/
Energy for Maintenance (NEM), Net Energy for Gain
day of 3.5% bf milk, gaining 0.5 kg/day
(NE
G) or Net Energy for Lactation (NEL).
at 300 days in milk, 220 days pregnant.
Feeds & Feeding 93
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The Role of Fibre in
Dairy Cattle Nutrition
The rumen fibre mat functions
as a particle sorting system
and stabilizes fermentation by
trapping fine, dry particles.
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INDEX
Ruminant animals require physical fibre in their diets to keep
the rumen functioning normally. Chewing is required to break
down large fibre particles and chewing promotes salivation. A
cow producing 30 to 40 kg of milk may secrete as much as 200
litres of saliva daily. This amount of fluid being produced high
up in the digestive tract washes feed particles through the
rumen into the lower parts of the system. In addition, saliva
contains buffers which serve to prevent the contents of the
rumen from becoming too acidic.
Physical fibre also provides a ‘tickle factor’ which stimulates
rumen contractions. These help to keep the rumen contents
well mixed and to force fluid and small particles further down
the digestive tract. A third function of long forage
is the maintenance of a fibre mat which floats in
GAS
the rumen and functions as a particle sorting
ESOPHAGUS
FIBRE MAT
system. Long particles near the top of the
mat are the first to be regurgitated for cud
chewing. Chewing subdivides and adds
water to the particles. When they re-enter the
EXIT FROM RUMEN
rumen, they ‘float’ at a lower level than the
longer, drier particles they were derived from.
A functional mat also stabilizes rumen
fermentation by trapping fine particles,
slowing their rate of breakdown by reducing
exposure to rumen microbes.
Feeds & Feeding 94
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The Role of Protein in
Dairy Cattle Nutrition
DPP
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INDEX
Dairy cattle manufacture a huge array of different proteins,
ranging from milk casein to actin in muscle, hemoglobin which
carries oxygen in blood and pepsin which digests dietary
protein in the small intestine. To synthesize these proteins, the
animal requires amino acids, the basic subunits of all proteins.
Of the 20 common amino acids, 10 are essential—they must
be available from the digestive tract because animals cannot
make them.
Ruminant animals do not require dietary amino acids or True
Protein to support maintenance or very low levels of
production. This is because the animals’ amino requirements
are satisfied by digesting microbial protein that passes down
UNDEGRADABLE
DEGRADABLE
INTAKE
PROTEIN
The high producing dairy cow
requires both degradable and
undegradable dietary true
protein to supply the amino
acid requirements of rumen
microbes and the cow herself.
AMMONIA
AMINO ACIDS
MICROBIAL
PROTEIN
INDIGESTIBLE
DIGESTIBLE
AMINO
ACIDS
BODY
PROTEIN
MILK
PROTEIN
continued...
The Role of Protein in
Dairy Cattle Nutrition
(continued)
the digestive tract from the rumen. Rumen bacteria are able to
manufacture microbial protein from dietary Non-protein
Nitrogen sources that yield ammonia after entering the
rumen. For example, urea is broken down to ammonia by
bacteria that produce the enzyme urease.
To support anything beyond very low production, a few of the
essential amino acids are required in the diet to support the
efficient processing of forages by rumen microbes. At the very
high levels of production expected of today’s lactating dairy
cow, high quality protein which is resistant to microbial
degradation must also be fed. Such Rumen Undegradable
Protein must be digestible in the small intestine and must
supply a mixture of amino acids which complements the
amino acids provided by microbial protein.
C
N
E
S
S
£
C
I
N
Ø
A
N E
S N
Ø S
N
I
I
£ A C
A
I
A
C
S
The blend of amino acids available to the cow is a
combination of those released by intestinal
A digestion of both microbial and undegraded feed
proteins. The total amount of protein available to
C
the animal for metabolism is referred to as
£
Metabolizable Protein. When the blend of amino
acids available in Metabolizable Protein is not exactly what the
cow requires, excess amino acids are broken down in the liver,
much of the nitrogen (N) being released as urea and excreted.
This process is illustrated in the diagram on the left.
£
C
I
CASEIN
S CASEIN
I
N
A
Ø
In this illustration, letters of the
alphabet represent amino
acids. Synthesis of milk
protein requires equal proportions of the 6 letters that spell
the word CASEIN. Here, the
letter E is limiting so only two
words can be synthesized.
The other letters are surplus
and cannot be used.
Ø
Net Protein is that fraction of metabolizable protein which
contributes to lean tissue growth and milk production.
Another major fraction is required for tissue turnover, a
process by which tissues are continually replaced by new
tissue.
Feeds & Feeding 96
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CURRICULUM
The Role of Minerals in
Dairy Cattle Nutrition
DPP
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INDEX
A number of minerals are essential for maintenance, growth,
production and reproduction of dairy animals. Those required
in large amounts are referred to as macrominerals and
include calcium, phosphorus, sodium, chlorine, potassium,
magnesium, and sulfur. The macrominerals are important
structural components of bone and other tissues and serve as
important constituents of body fluids. They play vital roles in
the maintenance of acid-base balance, osmotic pressure,
membrane electric potential and nervous transmission.
Minerals required in smaller amounts are referred to as microor trace minerals. . This group includes cobalt, copper, iodine,
iron, manganese, molybdenum, selenium, zinc, and perhaps
chromium and fluorine. The trace minerals are present in body
tissues in very low concentrations and often serve as
components of enzymes and hormones.
Specific functions of the essential minerals and signs of their
deficiency are as follows:
Macrominerals:
Calcium (Ca): A component of body fluids, muscle, bone and
the blood clotting mechanism. Regulates heart beat, muscle
function and nerve impulses.
Signs of Deficiency: softened, deformed, bones; Rickets and
Osteomalacia.
Chlorine (Cl): Responsible for the regulation of fluids and acidbase balance in body systems; secreted as HCl in the
abomasum.
Signs of Deficiency: unthrifty appearance, rough coat, rapid
weight loss.
...continued
The Role of Minerals in
Dairy Cattle Nutrition
(continued)
Magnesium (Mg): Has a role in skeletal structure, nerve
transmission and enzyme function.
Signs of Deficiency: In calves: poor growth and deformed
bones. In mature cattle: Grass Tetany.
Phosphorus (P): Responsible for bone formation; constituent of
body tissues, blood, phospholipids, nucleotides and
enzymes.
Signs of Deficiency: Rickets, Osteomalacia, eating dirt,
reproductive problems.
Potassium (K): Maintains fluid balance; responsible for nerve
impulses, muscle contraction, oxygen and carbon dioxide
transport, acid-base balance and enzyme activation.
Signs of Deficiency: Weight loss and decreased appetite
Sodium (Na): Regulation of body fluids and acid-base balance;
responsible for the active transport of glucose and amino
acids throughout the body; involved in muscle contraction
and bile function.
Signs of Deficiency: Same as for chloride.
Sulphur (S): Required in amino acids, vitamins and coenzymes;
regulates acid-base balance and carbohydrate and lipid
metabolism; found in most body fluids, blood cells and
heparin (which regulates blood clotting).
Signs of Deficiency: Decreased weight gain.
Trace Minerals:
Cobalt (Co): Used by rumen microbes to synthesize Vitamin B12.
Signs of Deficiency: Rough coat, scales, anestrus, abortion,
emaciation, anemia.
Copper (Cu): A component of enzyme systems.
Signs of Deficiency: Anemia, lack of hair pigment, lesions
and hemorrhages.
Iron (Fe): Required in hemoglobin in blood and myoglobin in
muscles; a component of enzymes.
Signs of Deficiency: Anemia.
Iodine(I): A component of thyroxine which is secreted by the
thyroid gland to regulate basal metabolism, growth,
reproduction and lactation.
Signs of Deficiency: When dams are deficient, newborns will
have goitre.
...continued
The Role of Minerals in
Dairy Cattle Nutrition
(continued)
Manganese (Mn): Component of bone matrix; responsible for
the maintenance of equilibrium; a constituent of enzymes,
glycoproteins and transferases; has a role in lipid and
carbohydrate metabolism
Signs of Deficiency: Enlarged joints, stiffness, twisted legs,
general weakness and reduced bone strength.
Selenium (Se): Enzyme component; works as an antioxidant
along with Vitamin E.
Signs of Deficiency: White muscle disease in calves;
reproductive problems in adults.
Zinc (Zn): constituent of enzymes, particularly those involved in
carbohydrate metabolism; has a role in the structure of DNA
(deoxyribonucleic acid) and RNA (ribonucleic acid);
important role in the synthesis of some proteins, especially
keratin (the protein of skin, hoof and horn).
Signs of Deficiency: Dermatitis, slowed growth, anorexia,
rough coat, bone density, hypogonadism, suppression of
secondary sex characteristics, dwarfism, delayed wound
healing.
Feeds & Feeding 99
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DPP
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INDEX
The Role of Vitamins in Vitamins are classified as either fat-soluble or water-soluble.
Water soluble vitamins include thiamine (B1), riboflavin (B2),
Dairy Cattle Nutrition
niacin, pantothenic acid, folic acid, biotin, choline, myoinositol,
para-aminobenzoic acid, vitamins B6, B12, and C. These
vitamins can all be synthesized either by microbes or within
body tissues, so they are not normally supplemented.
However, they are not stored in the body and there is some
evidence that supplementation of folic acid and vitamin B12 in
the diets of high producing cows might be beneficial. Biotin
supplementation has been shown to reduce the incidence of
some types of hoof lesions and, Niacin is often included in
transition diets for fat cows although evidence to support this
use is inconclusive.
Fat soluble vitamins include A, D, E, and K. These vitamins are
transported through the body in association with lipids. They
are also absorbed and stored with fat in the body. Vitamin K
can be synthesized by rumen microbes and does not need to
be supplemented. Vitamins A, D, and E must either be
provided in the diet or administered by intramuscular or
subcutaneous injection.
Specific functions of the vitamins and signs of their deficiency
are as follows:
Vitamin A: Essential to the development of the epithelial cells,
reproductive success, bone growth and proper vision.
Natural sources of Vitamin A include green plants and organ
tissues.
Signs of Deficiency: Tough skin, reproductive disorders,
reduced bone growth, blindness, thinning, diarrhea and
nervous behaviour.
...continued
The Role of Vitamins in Vitamin D: Prevention of Milk Fever in lactating cows by
increasing the absorption of calcium and phosphorus in the
Dairy Cattle Nutrition
small intestine and mobilization from bone. Vitamin D is
(continued)
produced in the skin of animals exposed to sunlight. If
animals are housed indoors, then Vitamin D must be
supplemented. Natural sources of Vitamin D include good
quality forages and fish oils.
Signs of Deficiency: Rickets, Osteomalacia, Osteoporosis.
Vitamin E: In conjunction with selenium, vitamin E is an
antioxidant. Natural sources include germ or germ oils of
plant seeds and green plants.
Signs of Deficiency: White Muscle Disease in newborn
calves; reproductive disorders in mature animals.
Feeds & Feeding 101
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The Role of Water in
Dairy Cattle Nutrition
DPP
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INDEX
Water is the most important nutrient for dairy cattle. It is
required for all of life’s processes:
• transport of nutrients and other compounds to and from
cells;
• digestion and metabolism of nutrients;
• elimination of waste materials as urine, feces and respiratory
water vapour;
• removal of excess heat from the body through evaporation;
• maintenance of fluid and ion balance, and;
• provision of a fluid environment for the developing fetus.
The total body water content of dairy cattle is 56 to 81 percent
of body weight, depending on physiologic stage and body
composition. Cows in early lactation have more body water
(69% of body weight) than cows in late lactation (62%). Late
gestation dry cows are intermediate in body water content
(65%). Fat cows have lower body water content than thin
lactating cows and younger, leaner animals have a higher
water content than older animals.
Body water is divided into intracellular and extracellular
compartments. Intracellular (within the cell) water is the
largest compartment, accounting for about two-thirds of the
water in the body. The extracellular (outside the cell) fluid
includes water around cells and connective tissue, water in
plasma, and water in the gastrointestinal tract. Intestinal water
accounts for 10-35 percent of body weight—in early lactation
cows it is about 15%; in pregnant and late lactation cows it is
about 10-11%.
Feeds & Feeding 102
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Growth Targets
Standard curves for weight
and hip height growth of US
Holsteins.
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The ultimate objective of a successful calf and heifer rearing
program is to achieve maximum first lactation milk production
from an animal who produces her first calf at 24±2 months of
age. The two graphs below illustrate standard growth curves
for US Holstein females between 1 and 24 months of age. As
shown, growth of individual animals will vary, depending upon
both genetics and nutrition.
800
700
BodyWeight,kg
600
500
le
nti
e
rce tile erag
e
v
p
a
n
th ce
95 h per
t
ile
5
7
ent
erc ntile
p
h
e
25t perc
5th
400
300
200
First bred TBW = 55% of MSBW
100
0
First post-calving TBW = 82% of MSBW
0
2
4
6
8 10 12 14 16 18 20 22 24
Age, months
160
Hip Height, cm
Second post-calving TBW = 92% of MSBW
The table below gives some examples:
140
tile
cen
per entile
h
t
95 perc
h
ile
75t ercent
p
le
i
t
h
25t percen
h
t
5
120
100
ge
avera
80
0
Growth targets can be stated with reference
to mature shrunk body weight (MSBW) which
is the weight of a cow after she delivers her
third calf and following an overnight fast
without feed or water. The potential MSBW of
a heifer can be predicted from the weight of
her dam. Target body weights (TBW) are as
follows:
0
2
4
6
8 10 12 14 16 18 20 22 24
Age, months
Predicted
MSBW, kg
550
600
650
700
750
Target Body Weights, kg
First
First
Second
Bred Post-Calf
Post-Calf
303
330
358
385
413
451
492
533
574
615
506
552
598
644
690
Feeds & Feeding 103
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DPP
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INDEX
Monitoring Heifer
Growth
The success of a heifer-rearing program can be evaluated by
monitoring the height and weight of calves and heifers and
comparing the results against breed averages for a specific
age group. Although most dairy producers, consultants,
Proper placement of weigh tape
feed industry representatives, and veterinarians can
Heart girth Withers
recognize underconditioned or overconditioned
animals, it is difficult to visually determine whether
a heifer’s height or weight is normal for her age.
To estimate a dairy animal’s body weight, use a
weight tape, which is accurate to within 5 to 7 percent of
the actual body weight. Make certain that the animal is
standing with her head upright. Pull the weight tape snug,
but not too tight, around the heart girth just behind the front
legs and shoulder blades.
65”
Proper placement
of measuring stick
When measuring a heifer’s wither height, stand her on a clean,
hard, level surface, hold her head upright and make sure that
she is standing comfortably without pulling against her halter.
Measure at the highest point of the withers. Hip height can be
measured with less concern about
the orientation of the head.
Level
Read here
Close-up of heifer
measuring stick
25”
source: J. Heinrichs and B. Lammers, Monitoring Dairy Heifer Growth, Penn
State University
Feeds & Feeding 104
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Efficiency of Intestinal
Immunoglobulin Absorption (%)
Colostrum
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At birth, the calf has no protection against infectious diseases.
She acquires immunity by consuming colostrum, a rich source
of both essential nutrients and antibodies which provide
immunity to infection. To assure absorption of antibodies,
colostrum must be fed immediately after birth. As illustrated
in the diagram on the left, the calf’s ability to
absorb antibodes declines very rapidly after
Maximum Absorption
birth.
50
40
Colostrum is the first milk produced by the dam.
Once it is removed, subsequent milkings yield
secretions which are much lower in nutrients
and antibodies than the first. This is shown in
the table below.
30
20
Average Absorption
10
0
0
Birth
6
12
18
Hours After Birth
Absorption of colostrum
through the calf’s intestine
declines very rapidly after birth.
24
A 55 kg calf requires 3 litres of colostrum within
an hour after birth and another 3 litres within
the next 4 hours. Smaller calves should be fed
proportionately less. Hand feeding is the only
way to assure consumption.
1
Item
Milking number
(cows milked twice daily)
2
3
4
5
11
Whole
Colostrum ---Transitional Milk--- Milk
Total solids, %
Total protein, %
Casein, %
Immunoglobulins, %
Fat, %
Lactose, %
Minerals, %
Specific gravity
23.9
14.0
4.8
6.0
6.7
2.7
1.11
1.056
17.9
8.4
4.3
4.2
5.4
3.9
0.95
1.040
14.1
5.1
3.8
2.4
3.9
4.4
0.87
1.035
13.9
4.2
3.2
0.2
4.4
4.6
0.82
1.033
13.6 12.9
4.1 4.0
2.9 2.5
0.1 0.09
4.3 4.0
4.7 4.9
0.81 0.74
1.033 1.032
Feeds & Feeding 105
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Feeding Milk to Calves
DPP
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Four to six litres of colostrum must be fed within the first few
hours after birth for the calf to absorb the antibodies which
will provide passive immunity for the first few months of life.
After these initial feedings, colostrum and transition milk
should be fed as long as they are available—usually for 3 to 4
days. Both contain significantly higher concentrations of
nutrients than the milk which is secreted later.
After receiving colostrum and transition milk for the first few
days of life, calves are fed either milk or milk replacer until
weaning. The majority of calves on western Canadian dairy
farms receive ‘hospital’ milk—milk which is unsuitable for
shipping due to its poor quality or because the cow from
which it is taken has been treated with antibiotics. Marketable
(in-quota) milk may be fed when insufficient hospital milk is
available but its high value compared to milk replacer makes it
too expensive to feed routinely.
There are risks inherent in feeding hospital milk:
• It may contain infectious organisms that can cause disease in
the calves. Johne’s Disease, Mycoplasma, E. coli, Bovine Virus
Diarrhea and Pasteurella are of particular concern.
• Antibiotic residues can inhibit the development of the
bacteria that normally populate the healthy gut.
To reduce the risk of passing infection to the calves,
some producers pasteurize their hospital milk.
Commercial pasteurizers, such as the one shown on
the left, are available for this purpose but generally
require the feeding of 300+ calves per day to make
them economically feasible.
continued...
Feeding Milk to Calves
(continued)
When kept with her dam, a week-old calf will nurse about 10
times per day, consuming about 1 litre of milk each time—
approximately 10 litres per day. When allowed unlimited
consumption of milk from an artificial teat, calves nurse an
average of 25 times/day, consuming about 8.5 litres of milk per
day at 7 days of age. However, many calves are fed only 2 litres
of milk twice per day regardless of their size or the ambient
temperature. It is strongly recommended that the amount be
increased to 3 litres twice a day for larger calves and when
ambient temperatures below -10oC significantly increase
maintenance energy requirements.
Traditional liquid feeding programs for calves deliberately
restrict intake and growth. The rationale for this is that liquid
feeds are expensive and that calves will compensate for their
slower early growth by growing more quickly after weaning
onto solid feeds. In the past several years, there has been
increasing interest in ‘accelerated’ growth programs for
calves on liquid diets.
Feeds & Feeding 107
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Milk Replacers
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Although most dairy farms in western Canada rely on
‘hospital’ milk for feeding to their calves, milk replacers are
fed in some situations:
• when the supply of hospital milk is limited;
• when it is recognized that hospital milk poses significant risk
to the health of the calves;
• when the price of milk replacer is significantly less that the
market value of shippable milk.
Milk replacers vary in composition and quality. The table on
the left compares protein, fat and energy levels in several
commercial products with those in whole milk. ‘All-milk’
products contain only milk protein, usually
Protein Fat
MEa
derived from whey. When the price of skim milk
Example
%
%
Mcal/kg
powder is low, they may also contain milk
caseins—the proteins that are used to make
A
22
12
4.41
cheese. Less expensive milk replacers may
B
22
20
4.80
contain soy- or fish-derived proteins, some of
C
18
21
4.78
which are not well digested by young calves.
D
20
20
4.78
E
20
20
4.78
Fat content is another important aspect of milk
F
28
17
4.75
replacer quality, primarily affecting the energy
G
28
15
4.65
value of the product. Both fat and protein quality
Whole Milk
25
30
5.33
affect the ease with which milk replacers mix with
a
ME is Metabolizable Energy
water and stay in suspension.
Composition comparison of
several commercial milk
replacers versus wholemilk.
In the US, antibiotics are commonly added to milk replacers in
an attempt to protect calves from infection. Although
permitted, this practice is less common in Canada.
continued...
Milk Replacers
(continued)
Milk replacers are typically fed at a daily rate of about 500
grams of powder dissolved in 4 litres of water, split into two
equal feedings. It is recommended that this rate be increased
by approximately 50% for larger calves and when the ambient
temperature falls below -10oC. Increased feeding rates can be
achieved either by adding more powder to the same amount
of water (e.g., 750 grams in 4 litres) or by feeding more mixed
replacer at the usual dilution rate (e.g., 750 grams in 6 litres).
Feeds & Feeding 109
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Nutrient Requirements
of Calves Fed Milk or
Milk Replacer Only
Live Daily
Weight Gain
kg
g
25
30
40
45
50
0
200
400
0
200
400
0
200
400
600
0
200
400
600
0
200
400
600
DM
Intakea
kg
0.24
0.32
0.42
0.27
0.36
0.47
0.34
0.43
0.55
0.69
0.37
0.46
0.59
0.74
0.40
0.45
0.63
0.78
DPP
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The following table is adapted from the US National Research
Council’s ‘Nutrient Requirements of Dairy Cattle’, 7th Revised
Edition, published in 2001.
--------------- Energy --------------NEM
NEG
ME
DE
Mcal
Mcal
Mcal
Mcal
0.96
0.96
0.96
1.10
1.10
1.10
1.37
1.37
1.37
1.37
1.49
1.49
1.49
1.49
1.62
1.62
1.62
1.62
0
0.26
0.60
0
0.28
0.65
0
0.31
0.72
1.16
0
0.32
0.75
1.21
0
0.34
0.77
1.26
1.12
1.50
2.00
1.28
1.69
2.22
1.59
2.04
2.63
3.28
1.74
2.21
2.82
3.50
1.88
2.37
3.00
3.70
1.17
1.56
2.08
1.34
1.76
2.31
1.66
2.13
2.74
3.41
1.81
2.30
2.94
3.64
1.96
2.47
3.13
3.86
---- Protein ---ADP
CP
g
g
18
65
113
21
68
115
26
73
120
168
28
76
123
170
31
78
125
173
20
70
121
23
73
124
28
79
129
180
30
81
132
183
33
84
135
185
Vitamin
A
IU
2,750
2,750
2,750
3,300
3,300
3,300
4,400
4,400
4,400
4,400
4,950
4,950
4,950
4,950
5,500
5,500
5,500
5,500
a Dry Matter intake necessary to meet ME requirements for calves fed milk or milk replacer
containing primarily milk proteins and containing 4.75 Mcal ME/kg of dry matter.
Feeds & Feeding 110
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Calf Starter
photo of calf starter
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Dry feed intake drives rumen development. The sooner the
calf is consuming dry feed, the sooner can she be weaned.
Palatable, highly nutritious starter along with fresh water
should be offered by a week of age. Small quantities, placed in
a clean pail should be offered and cleaned out daily. Calves
can be weaned when they are regularly consuming 1 kg of
starter a day. Starter feeding should continue until the calf is
consuming 2 kg daily. Well managed calves in a clean, dry
environment will normally consume this amount by about 8
weeks of age.
Calf starter should contain 20-22% Crude Protein (dry matter
basis). Protein ingredients should be of high quality because,
at this stage of development, the calf’s digestive system is
similar to that of a single-stomached animal—the rumen is
only just starting to become functional. Soymeal is the most
common choice of protein ingredients due to its good balance
of amino acids and its palatability. Fresh ingredients, textured
grains, added flavour and intact pellets with minimal fines will
improve palatability and intake.
Calf starter should contain a coccidiostat such as Deccox®,
Bovatec® or Rumensin® to control coccidia, a parasite that
frequently inhabits the gut of young calves.
Feeds & Feeding 111
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Conventional versus
‘Accelerated’ Calf
Feeding Programs
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Traditionally, calves have been fed limited amounts of milk or
milk replacer to promote dry feed consumption, rumen
development and early weaning. As long as they remain
healthy, calves generally exhibit compensatory (‘catch up’)
growth after weaning. Under most milk and feed pricing
situations, there is an economic advantage to this strategy.
In recent years, researchers have proposed programs where
calves are offered nutrient intakes which are closer to those
they would achieve if left with their dams. Results have been
mixed. The photo below illustrates differences in growth of
calves reared conventionally versus those on an accelerated
program. In some trials, accelerated calves have maintained
their growth advantage well beyond weaning. In others, the
conventionally fed calves have gained more rapidly after
weaning, reducing or eliminating the early growth advantage
of the accelerated calves.
Calves raised on conventional
liquid feeding program (left
calf in each photo) compared
with calves raised on accelerated program (right calf in
each photo) at 8 weeks of age
(left photo) and 14 weeks of
age (right photo).
Feeds & Feeding 112
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Nutrient Requirements The following table is adapted from the US National Research
Council’s ‘Nutrient Requirements of Dairy Cattle’, 7th Revised
of Calves Fed Milk or
Milk Replacer and Starter Edition, published in 2001.
Live Daily
DM
Weight Gain Intakea
kg
g
kg
40
45
50
55
60
a
0
200
400
600
0
200
400
600
0
200
400
600
800
0
200
400
600
800
0
200
400
600
800
0.40
0.51
0.66
0.83
0.44
0.56
0.71
0.88
0.47
0.60
0.76
0.94
1.13
0.51
0.63
0.80
0.99
1.18
0.54
0.67
0.84
1.04
1.24
--------------- Energy --------------NEM
NEG
ME
DE
Mcal
Mcal
Mcal
Mcal
1.37
1.37
1.37
1.37
1.49
1.49
1.49
1.49
1.62
1.62
1.62
1.62
1.62
1.74
1.74
1.74
1.74
1.74
1.85
1.85
1.85
1.85
1.85
0
0.31
0.72
1.16
0
0.32
0.75
1.21
0
0.34
0.77
1.26
1.78
0
0.35
0.80
1.30
1.84
0
0.36
0.83
1.34
1.90
1.66
2.14
2.76
3.44
1.81
2.31
2.96
3.67
1.96
2.48
3.15
3.89
4.69
2.11
2.64
3.33
4.10
4.93
2.25
2.80
3.51
4.31
5.16
1.78
2.29
2.95
3.68
1.94
2.47
3.16
3.93
2.10
2.65
3.37
4.17
5.02
2.25
2.83
3.57
4.39
5.27
2.41
3.00
3.76
4.61
5.52
---- Protein ---ADP
CP
g
g
25
78
128
178
31
80
130
180
33
83
133
183
233
36
85
135
185
236
38
88
138
188
238
33
90
148
205
36
93
151
209
38
96
154
212
270
41
99
157
215
273
44
102
159
217
275
Vitamin
A
IU
4,400
4,400
4,400
4,400
4,950
4,950
4,950
4,950
5,500
5,500
5,500
5,500
5,500
6,050
6,050
6,050
6,050
6,050
6,600
6,600
6,600
6,600
6,600
Dry Matter Intake is the total necessary to meet ME requirements for calves fed milk or
milk replacer (MR) plus starter assuming milk or MR contains ME at 4.75 Mcal/kg of DM and
starter ME at 3.28 Mcal/kg. It is also assumed that MR provides 60 percent and starter 40
percent of dry matter intake; thus, dry matter consumed contained ME at 4.16 Mcal/kg.
Feeds & Feeding 113
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Feeding Hay to Calves
Differences in development of
the rumen in 6 week old calves
fed milk only (A), milk and hay
(B) or milk and grain (C).
A
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For many years, it was believed that feeding hay to young
calves would promote rumen development. The rationale was
that physical ‘scratch’ was needed to start the rumen working.
It is now known that the main stimulus to rumen development
is volatile fatty acid (VFA) production from feed fermentation.
Because the amounts of VFA produced from grain are higher
than those from forage, the rumen develops much faster when
grain-based diets are fed, as shown in the photographs below.
For this reason, hay should not be offered to calves until after
they are weaned.
B
C
Another reason for not feeding hay to calves before weaning is
that the small amount they can consume contributes little to
their nutrient requirements. Any hay that they do consume
video clip used with permission will limit starter intake and reduce total daily nutrient intake.
of Penn State University
Most of the hay they do not consume becomes bedding.
Click here to see a video
about rumen development
continued...
Feeding Hay to Calves
(continued)
Although not required by calves before weaning, forage is
important later, to promote the growth of the muscular layer
of the rumen and to maintain the health of the papillae—the
small projections lining the inside of the rumen (shown in
photo C on the previous page). Rumen papillae can grow too
rapidly in response to high levels of VFA. When this happens,
they may clump together, reducing the surface area available
for absorption. Also, some ‘scratch’ is needed to keep the
papillae from forming layers of keratin (skin-like tissue), which
can also inhibit VFA absorption.
A common recommendation is to start offering high quality
hay immediately after weaning at 5 to 7 weeks of age. If calves
are not weaned until 8 to 10 weeks of age, feed a limited
amount (500 grams/day) of the best hay available from about
6 weeks of age. The amount should be limited to ensure that
hay consumption will not significantly reduce starter intake.
Feeds & Feeding 115
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Weaning
Typical starter intake pattern
for well-managed Holstein
heifer calves.
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Many producers wean calves when they reach a particular
age—often 8-10 weeks. Although this might be effective for
most, some calves are not ready to be weaned at that
particular age while many are ready much earlier. The critical
question is: ‘How well developed are their rumens?”. Since you
can’t actual monitor rumen development, the next best
indicator is dry feed intake.
4
Starter Intake, kg/day
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A healthy calf routinely consuming a kilogram of
starter daily can be weaned immediately. The
age at which she has achieved that level of intake
is mainly a function of management. Calves
raised in a clean, dry environment who are
offered fresh, nutritious and palatable starter and
water in clean containers each day from their first
week of life can usually consume that level of
starter by 6 weeks of age.
3
2
1
0
0
1
2
3
4 5 6 7
Calf Age, weeks
8
9
10
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Feeding Calves from
Weaning to Breeding
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Between weaning and conception at 15 months of age, the
heifer will gain from 200 to 400 kg and grow in height by 30 to
50 cm. Expected growth rates, derived from standard curves
for US Holstein heifers, are given in the table below.
Continue feeding starter and start offering high quality hay
immediately after weaning. If calves are not weaned until 8 to
Expected growth rates for
10 weeks of age, feed a limited amount (500 grams/day) of the
Holstein heifers.
best hay available from about 6 weeks of age. A grower ration,
containing 16-18% crude protein (dry matter basis)
Weight Height
and Rumensin® (to improve feed efficiency) can
kg
mm
replace starter when calves are around 4 months of
gain per day
age and consuming 2 kg of starter daily. The grower
protein level and the amount to feed will depend on
5th percentile
0.54
83
hay consumption and quality. Recognize the difference
25th percentile
0.68
96
between the amount of hay offered and the amount
Median
0.78
103
consumed—much of the hay offered can become
75th percentile
0.85
109
bedding if feeders are not well designed.
Beginning at about 6 months of age, heifers can be fed a
silage-based total mixed ration (TMR), where all ingredients
are combined in a single mix. This strategy provides better
control of diet composition and intake than does separate
feeding of forage and concentrate. In either case, an
ionophore such as Rumensin® is normally added to the
concentrate portion of the ration to promote efficient growth.
The few months before a heifer reaches puberty (normally at
9-10 months of age) is a critical time for offering a wellbalanced ration, designed to support lean tissue growth. If the
diet contains excess energy, the heifer will begin to gain body
condition (fat). Fat that is laid down in the developing
mammary gland can have negative effects on milk secretory
tissue development and milk production later in life.
Feeds & Feeding 117
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Nutrient Requirements
of Weaned Calves
Live Daily
DM
Weight Gain Intakea
kg
g
kg
60
70
80
90
100
600
700
800
600
700
800
600
700
800
600
700
800
900
600
700
800
900
1.56
1.71
1.87
1.70
1.86
2.03
1.83
2.00
2.18
2.09
2.28
2.48
2.68
2.22
2.42
2.63
2.84
DPP
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The following tables are adapted from the US National
Research Council’s ‘Nutrient Requirements of Dairy Cattle’,
7th Revised Edition, published in 2001.
--------------- Energy --------------NEM
NEG
ME
DE
Mcal
Mcal
Mcal
Mcal
1.85
1.85
1.85
2.08
2.08
2.08
2.30
2.30
2.30
2.51
2.51
2.51
2.51
2.72
2.72
2.72
2.72
1.34
1.62
1.90
1.42
1.71
2.00
1.49
1.79
2.10
1.55
1.87
2.19
2.52
1.61
1.94
2.27
2.62
4.83
5.31
5.80
5.26
5.77
6.29
5.68
6.21
6.75
6.07
6.62
7.19
7.78
6.45
7.02
7.62
8.22
5.23
5.70
6.19
5.66
6.16
6.67
6.07
6.59
7.13
6.46
7.00
7.57
8.15
6.83
7.40
7.99
8.59
---- Protein ---ADP
CP
g
g
213
241
269
219
247
275
225
253
281
231
260
288
317
237
265
294
323
284
322
359
292
330
367
300
337
375
309
346
385
423
316
354
392
430
Vitamin
A
IU
6,600
6,600
6,600
7,700
7,700
7,700
8,800
8,800
8,800
9,900
9,900
9,900
9,900
11,000
11,000
11,000
11,000
abbreviations: BW - Body Weight; ADG - Average Daily Gain; DMI - Dry Matter Intake; TDN Total Digestible Nutrients; NEM - Net Energy for Maintenance; NEG - Net Energy for Gain;
ME- Metabolizable Energy; RDP - Rumen Degradable Protein; RUP - Rumen Undegradable
Protein; CP - Crude Protein; Ca - Calcium; P - Phosphorus
continued...
BW
kg
150
200
250
300
350
400
450
ADG DMI TDN
--- kg/d --- %
0.5
0.7
0.9
1.1
0.5
0.7
0.9
1.1
0.5
0.7
0.9
1.1
0.5
0.7
0.9
1.1
0.5
0.7
0.9
1.1
0.5
0.7
0.9
1.1
0.5
0.7
0.9
1.1
4.1
4.2
4.2
4.2
5.1
5.2
5.2
5.2
6.0
6.1
6.2
6.2
6.9
7.0
7.1
7.1
7.7
7.9
8.0
8.0
8.5
8.7
8.8
8.8
9.3
9.5
9.6
9.6
58.4
61.7
65.3
69.2
58.4
61.7
65.3
69.2
58.4
61.7
65.3
69.2
58.4
61.7
65.3
69.2
58.4
61.7
65.3
69.2
58.4
61.7
65.3
69.2
58.4
61.7
65.3
69.2
NEM NEG ME RDP RUP
------ Mcal/d ------ ---- g/d ----
RDP RUP CP
--------- % ---------
Ca
P
--- g/d ---
3.57
3.57
3.57
3.57
4.44
4.44
4.44
4.44
5.24
5.24
5.24
5.24
6.01
6.01
6.01
6.01
6.75
6.75
6.75
6.75
7.46
7.46
7.46
7.46
8.15
8.15
8.15
8.15
8.9
9.4
10.0
10.6
8.9
9.4
10.0
10.6
8.9
9.4
10.0
10.6
8.9
9.4
10.0
10.6
8.9
9.4
10.0
10.6
8.9
9.4
10.0
10.6
8.9
9.4
10.0
10.6
23
30
37
43
24
30
37
43
25
31
37
43
27
33
38
44
28
34
40
45
30
35
41
46
33
36
42
47
0.84
1.22
1.61
2.00
1.05
1.51
1.99
2.49
1.24
1.79
2.36
2.94
1.42
2.05
2.70
3.37
1.59
2.30
3.03
3.78
1.76
2.55
3.35
4.18
1.93
2.80
3.67
4.58
8.6 364
9.3 393
9.9 421
10.6 446
10.7 452
11.5 488
12.3 522
13.1 554
12.6 534
13.6 577
14.6 617
15.5 655
14.5 612
15.6 661
16.7 707
17.7 751
16.2 687
17.6 742
18.8 794
19.9 843
18.0 760
19.4 821
20.7 878
22.0 931
19.8 831
21.0 898
22.4 963
24.0 1015
167
230
292
352
148
205
260
314
131
182
232
280
114
161
205
248
99
141
181
218
86
124
159
192
75
108
139
180
4.1
5.5
6.9
8.3
2.9
4.0
5.0
6.0
2.2
3.0
3.7
4.5
1.7
2.3
2.9
3.5
1.3
1.8
2.3
2.7
1.0
1.4
1.8
2.2
0.8
1.1
1.4
1.9
13.0
14.9
16.9
18.9
11.9
13.4
15.0
16.6
11.1
12.4
13.7
15.1
10.6
11.7
12.9
14.1
10.2
11.2
12.3
13.3
9.9
10.9
11.8
12.8
9.7
10.7
11.6
12.5
11
13
16
18
12
14
17
19
13
15
17
19
14
16
18
20
15
17
19
21
16
18
20
22
17
19
21
23
abbreviations: BW - Body Weight; ADG - Average Daily Gain; DMI - Dry Matter Intake; TDN Total Digestible Nutrients; NEM - Net Energy for Maintenance; NEG - Net Energy for Gain;
ME- Metabolizable Energy; RDP - Rumen Degradable Protein; RUP - Rumen Undegradable
Protein; CP - Crude Protein; Ca - Calcium; P - Phosphorus
Feeds & Feeding 149
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Appendix A: Typical
Analyses of Western
Canadian Feeds
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The table on the following pages presents typical analysis
results for ingredients used in western Canadian dairy rations.
These estimates are not intended to substitute for the routine
analysis of feeds available on a particular farm.
When analysis results are received from the lab, compare them
with these ‘book’ values and with previous analyses of similar
feeds from the same farm. Results which are markedly higher
or lower should be questioned. Spurious values may be due to
poor sampling or errors in analysis. In either case, sampling
and analysis should be repeated until you are confident in the
results. It makes little sense to design feeding programs
around questionable analysis values.
Typical Analyses
Estimates
DM ADF NDF CP CF Ash
Ca
P
RUP NELa
% ---------------------- % of DM ---------------------- % CP Mcal/kg
Alfalfa
Hay, early vegetative
Hay, late vegetative
Hay, early bloom
Hay, mid bloom
Hay, full bloom
Silage, typical
Dehy, 17% protein
Dehy, 20% protein
Barley
Grain, typical
Silage, typical
Beet Pulp, typical
Blood Meal
Brewers Grains, wet, typical
Bromegrass
Fresh, early vegetative
Fresh, mature
Hay, late vegetative
Hay, late bloom
Canola
Meal, typical
Seeds, typical
Corn
Distillers Grains, typical
Grain, typical
Gluten Meal, typical
Silage, typical
Feather Meal, typical
Fish Meal, typical
87
87
87
87
87
40
90
90
28
29
31
35
37
31
35
31
38
40
42
46
50
42
45
42
23
20
18
17
15
18
18.9
22.2
4
10.2
3.5
9.2
3
9.6
2.6
9.1
2
8.9
3
9.6
3
10.6
3.7 11.3
1.8
1.54
1.41
1.41
1.25
1.41
1.52
1.74
0.35
0.29
0.22
0.24
0.22
0.22
0.25
0.3
20
22
24
27
30
23
59
59
1.50
1.42
1.35
1.30
1.23
1.32
1.38
1.40
88.5 7
37 32
91 33.6
90
22 23
19
54
48.4
42
12.7
11.2
9.3
97.2
28
2.1
2.1
0.5
1.1
6.5
2.6
7.6
5.3
4.8
4.8
0.06
0.55
0.66
0.33
0.35
0.36
0.27
0.11
0.28
0.6
25
25
36
80
49
1.94
1.50
1.79
1.50
1.50
34
57
88
89
31
44
35
43
56
72
65
68
18
6.4
16
10
3.7 10.7
2.2 10
2.6
9.4
2.3
8.4
0.5
0.2
0.32
0.3
0.3
0.26
0.37
0.35
40
50
44
48
1.69
1.28
1.55
1.33
90
95
19
8
24
26
39
30
3.9
42
0.7
0.4
1.2
0.66
35
30
1.74
3.85
93
88
90
32
93
93
17.0
3.0
3.9
30.5
-
42.0
9.0
13.3
50.0
-
29.0
10.0
73.0
8.8
89.2
77.4
8.7
7.6
4.3
1.6
2.2
2.0
3.0 10.0
7.5
4.2
10.8 11.8
0.38
0.03
0.11
0.29
0.22
3.87
1.30
0.29
0.78
0.24
0.81
2.37
54 1.99
52 1.96
55 1.99
30 1.60
71 1.35
60 1.72
continued...
6.8
4
abbreviations: DM - Dry Matter; ADF - acid detergent fibre; NDF - Neutral Detergent Fibre;
CP - Crude Protein; EE - Ether Extract (Lipids); Ca - Calcium; P - Phosphorus; RUP - Rumen
Undegradable Protein; NEL - Net Energy for Lactation
aconversions to other energy units follow this table
Typical Analyses
Estimates
DM ADF NDF CP CF Ash
Ca
P
RUP NELa
% ---------------------- % of DM ---------------------- % CP Mcal/kg
Oats
Grain, typical
Hay, boot stage
Orchardgrass
Fresh, early vegetative
Hay, early bloom
Hay, late bloom
Silage, typical
Pea
Seeds, typical
Perennial Ryegrass
Hay, typical
Silage, typical
Soy
Beans, typical
Meal, typical
Timothy
Hay, late vegetative
Hay, early bloom
Hay, mid bloom
Hay, full bloom
Hay, late bloom
Wheat
Grain, typical
Millrun, typical
90
86
16.0 32.0 11.6
32.0 58.0 17.5
23
89
91
35
31.0
34.0
45.0
39.5
3.4
6.5
0.07
0.41
0.32
0.21
17
25
1.77
1.64
55.0 18.4 4.9 11.3
61.0 15.0 2.8
8.7
72.0 8.4 3.4 10.1
60.0 12.5 3.0 10.0
0.58
0.27
0.26
0.57
0.54
0.34
0.30
0.40
40
46
48
27
1.64
1.47
1.20
1.31
3.6
0.12
0.45
25
2.01
86
35
30.0 41.0 8.6 2.2 11.5
39.5 60.0 12.5 3.0 10.0
0.65
0.57
0.32
0.40
46
27
1.45
1.42
92
89
11.0 13.0 42.8 18.8
6.0 8.0 54.0 1.7
5.5
7.3
0.27
0.22
0.65
0.73
26
28
2.11
1.94
89
90
89
89
88
29.0
32.0
36.0
38.0
40.0
55.0 17.0 2.8
61.0 15.0 2.9
67.0 9.1 2.6
68.0 8.1 3.1
70.0 7.8 2.8
7.1
5.7
6.3
5.2
5.4
0.66
0.53
0.48
0.43
0.38
0.34
0.25
0.22
0.20
0.18
30
34
38
42
46
1.50
1.38
1.30
1.25
1.20
90
90
4.0 11.4 15.9 1.6
13.3 20.0 17.8 4.4
2.0
9.1
0.06
0.11
0.40
1.00
25
25
2.04
1.82
90
9.0 19.3 23.4
5.1
2.6
1.4
abbreviations: DM - Dry Matter; ADF - acid detergent fibre; NDF - Neutral Detergent Fibre;
CP - Crude Protein; EE - Ether Extract (Lipids); Ca - Calcium; P - Phosphorus; RUP - Rumen
Undegradable Protein; NEL - Net Energy for Lactation
aconversions to other energy units follow this table
Table for Conversion of Feed NEL Values to NEM, NEG and TDN
NEL
NEM
NEG
TDN
NEL
NEM
NEG
TDN
NEL
NEM
NEG
TDN
1.10
1.11
1.12
1.13
1.14
1.15
1.16
1.17
1.18
1.19
1.20
1.21
1.22
1.23
1.24
1.25
1.26
1.27
1.28
1.29
1.30
1.31
1.32
1.33
1.34
1.35
1.36
1.37
1.38
1.39
1.40
1.41
1.42
0.96
0.97
0.99
1.00
1.02
1.03
1.05
1.06
1.07
1.09
1.10
1.12
1.13
1.14
1.16
1.17
1.19
1.20
1.21
1.23
1.24
1.26
1.27
1.28
1.30
1.31
1.32
1.34
1.35
1.36
1.38
1.39
1.40
0.41
0.43
0.44
0.45
0.47
0.48
0.49
0.51
0.52
0.53
0.55
0.56
0.57
0.58
0.60
0.61
0.62
0.64
0.65
0.66
0.67
0.69
0.70
0.71
0.72
0.74
0.75
0.76
0.77
0.79
0.80
0.81
0.82
49.8
50.2
50.6
51.0
51.4
51.8
52.2
52.7
53.1
53.5
53.9
54.3
54.7
55.1
55.5
55.9
56.3
56.7
57.1
57.6
58.0
58.4
58.8
59.2
59.6
60.0
60.4
60.8
61.2
61.6
62.0
62.4
62.9
1.43
1.44
1.45
1.46
1.47
1.48
1.49
1.50
1.51
1.52
1.53
1.54
1.55
1.56
1.57
1.58
1.59
1.60
1.61
1.62
1.63
1.64
1.65
1.66
1.67
1.68
1.69
1.70
1.71
1.72
1.73
1.74
1.75
1.42
1.43
1.44
1.46
1.47
1.48
1.50
1.51
1.52
1.54
1.55
1.56
1.58
1.59
1.60
1.61
1.63
1.64
1.65
1.67
1.68
1.69
1.70
1.72
1.73
1.74
1.75
1.77
1.78
1.79
1.81
1.82
1.83
0.83
0.85
0.86
0.87
0.88
0.89
0.91
0.92
0.93
0.94
0.95
0.96
0.98
0.99
1.00
1.01
1.02
1.03
1.04
1.06
1.07
1.08
1.09
1.10
1.11
1.12
1.13
1.14
1.16
1.17
1.18
1.19
1.20
63.3
63.7
64.1
64.5
64.9
65.3
65.7
66.1
66.5
66.9
67.3
67.8
68.2
68.6
69.0
69.4
69.8
70.2
70.6
71.0
71.4
71.8
72.2
72.7
73.1
73.5
73.9
74.3
74.7
75.1
75.5
75.9
76.3
1.76
1.77
1.78
1.79
1.80
1.81
1.82
1.83
1.84
1.85
1.86
1.87
1.88
1.89
1.90
1.91
1.92
1.93
1.94
1.95
1.96
1.97
1.98
1.99
2.00
2.01
2.02
2.03
2.04
2.05
2.06
2.07
2.08
1.84
1.86
1.87
1.88
1.89
1.91
1.92
1.93
1.94
1.95
1.97
1.98
1.99
2.00
2.02
2.03
2.04
2.05
2.06
2.08
2.09
2.10
2.11
2.12
2.14
2.15
2.16
2.17
2.18
2.20
2.21
2.22
2.23
1.21
1.22
1.23
1.24
1.25
1.26
1.28
1.29
1.30
1.31
1.32
1.33
1.34
1.35
1.36
1.37
1.38
1.39
1.40
1.41
1.42
1.43
1.44
1.45
1.46
1.47
1.48
1.49
1.50
1.51
1.52
1.53
1.54
76.7
77.1
77.6
78.0
78.4
78.8
79.2
79.6
80.0
80.4
80.8
81.2
81.6
82.0
82.4
82.9
83.3
83.7
84.1
84.5
84.9
85.3
85.7
86.1
86.5
86.9
87.3
87.8
88.2
88.6
89.0
89.4
89.8
Feeds & Feeding 153
GC
GREEN
CERTIFICATE
CURRICULUM
Glossary of Terms
DPP
TOC
DPP
INDEX
abomasum: the fourth compartment of the ruminant stomach;
function similar that of the monogastric stomach (e.g., the
human stomach) in its secretions of hydrochloric acid and
digestive enzymes.
acetic acid: one of the primary volatile fatty acids produced
by the microbial fermentation of feeds in the rumen and in
silage; the acid found in vinegar; chemical formula - C2H4O2.
active immunity: resistance to disease or infection developed
as a result of an animal’s own immune system producing
antibodies following infection or vaccination.
active transport: transport of ions, nutrients or other molecules
into a cell against a concentration gradient, requiring the
expenditure of energy.
adipose tissue: fatty tissue; refers to the body’s fat stores.
ad libitum: without restriction; refers to the practice of
allowing animals to consume feed or water to the limit of
their appetites.
alkaline: refers to a water solution having a pH greater than 7.
amino acid: one of 20 nitrogen-containing organic molecules
that appear in unique sequences joined by peptide bonds
to form peptides and proteins; 10 amino acids are
considered essential to mammals—they cannot be
synthesized by mammalian tissues.
ammonia (NH3): a colourless gas which is soluble in water.
Glossary of Terms
(continued)
ammonium salts: chemical compounds which, in water
solution, dissociate into ammonium cations (NH4+) and
anions such as chloride (Cl–) or sulphate (SO4=).
anemia: a condition where there is a lower than normal
amount of hemoglobin in the blood and red blood cell
production is reduced.
anestrus: absence of a heat or estrus cycle.
anion: a negatively charged atom or molecule such as chloride
(Cl–) or sulphate (SO4=).
antibiotic: a chemical substance such as penicillin or
tetracycline that is able to kill or inhibit the growth of
pathogenic (disease-causing) microorganisms.
antibody: blood proteins (immunoglobulins) which counteract
toxins or participate in the destruction of foreign
organisms.
antioxidant: a substance which will inhibit the oxidation of
other compounds.
ash: the residue remaining when a feed is burned in an
oxygen-enriched atmosphere; used to determine the total
mineral content of a feed.
atomic absorption spectrophotometry: a method of chemical
analysis in which atoms and molecules are identified by
the wavelength of radiation that they absorb.
bacterium: a sigle-celled micro-organism lacking a membranebound, structurally discrete nucleus and other subcellular
compartments possessed by higher organisms including
protozoa.
basic pH: on a scale of 1-9, a pH above 7 is considered basic, or
alkaline.
bloat: a condition in ruminants resulting from the build-up of
gas in the rumen and the inability to expel it.
Glossary of Terms
(continued)
bolus: the amount of feed in one swallow that passes through
the esophagus to the rumen-reticulum or in the reverse
direction for rumination (cud chewing).
borate-phosphate buffer: a solution containing salts of boric
and phosphoric acids used to estimate the solubility of
feed proteins.
bushel: a unit of volume used in measuring the bulk density
of feed grains; 1 bushel = 36.369 litres = 8.00 Imperial
gallons.
butyric acid: one of the primary volatile fatty acids produced
by the microbial fermentation of feeds in the rumen and in
silage; chemical formula - C4H8O2.
B-vitamins: a group of water soluble vitamins including
thiamine (B1), riboflavin (B2), niacin, pantothenic acid, folic
acid, biotin, choline, myoinositol, para−aminobenzoic acid,
vitamins B6, B12.
calorie: the amount of heat (energy) required to the raise the
temperature of one gram of water from 14.5° C to 15.5° C.
carbohydrate: a chemical compound or molecule composed
of carbon, oxygen and hydrogen in the ratio of 2H:1C:1O;
carbohydrates can be simple sugars such as sucrose and
fructose or complex polysaccharides such as cellulose and
starch.
carbon dioxide (CO2): a simple compound composed of one
atom of carbon and 2 of oxygen; green plants use CO2 to
manufacture carbohydrates and other organic
compounds; when mammals digest these compounds, CO2
is released.
carotene: a carotenoid pigment that gives a reddish color to
plants such as carrots and tomatoes; carotene is often
used as a vitamin supplement because animals can
convert it into Vitamin A.
carotenoid: one of a group of fat soluble red, orange, purple or
yellow pigments found in plants and some fungi.
Glossary of Terms
(continued)
cation: a positively charged atom or molecule such as
Ammonium (NH4+), Sodium (Na+) and Calcium (Ca2+).
cellulose: a complex structural carbohydrate (polysaccharide)
found in plants, consisting of long chains of glucose
subunits; although cellulose cannot be digested by
mammalian enzymes, certain rumen microbes can.
cetyl trimethyl ammonium bromide: an acidic detergent used in
the laboratory analysis of feeds for Acid Detergent Fibre.
chemical fibre: the fibre content of a feed, determined in the
laboratory as Acid Detergent or Neutral Detergent Fibre.
chlorophyll: the green plant pigment involved in capturing
solar energy which the plant uses in the process of
photosynthesis to manufacture carbohydrates from
carbon dioxide and water.
Coccidiosis: a disease caused by protozoa which colonize the
small intestine; signs include: bloody stool, strained
defecation and mild fever.
coccidiostat: a chemical substance such as Bovatec®, Deccox®
or Rumensin® that is able to kill or inhibit the growth of the
protozoa which cause Coccidiosis.
coenzyme: an organic, nonprotein molecule that binds with an
apoenzyme (a protein molecule) to form an active enzyme;
vitamins often function as coenzymes.
colorimetry: a laboratory analysis method in which chemical
concentrations are measured through changes in colour or
colour intensity.
compensatory growth: rapid growth in a young animal
following a period in which maximum growth has been
impaired by limited availability of nutrients; sometimes
called ‘catch-up’ growth.
concentrate: a feed ingredient other than forage.
coring tool: used to take feed samples by boring into a stack of
hay or concentrate mix and removing a core sample.
Glossary of Terms
(continued)
Cornell Net Carbohydrate and Protein System (CNCPS): a method
of determining animal requirements and formulating diets,
developed by scientists at Cornell University.
corticosteroid: an anti-inflammatory steroid hormone
produced by the cortex (inside layer) of the adrenal gland,
located near the kidney.
Crude Protein: nitrogen concentration multiplied by 6.25; used
to approximate the amount of protein in feed, based on
the assumption that feed proteins contain approximately
16% (1 ÷ 6.25) nitrogen.
cutin: a wax which, together with cellulose, forms the surface
layer of many plants.
degradability: the potential for a feed ingredient or
component to be broken down in the rumen.
deoxyribonucleic acid (DNA): the molecule that encodes
genetic information in the nucleus of every cell.
dermatitis: inflammation of the skin.
detergent: a chemical or agent used for cleaning.
diethyl ether: an organic chemical used to extract lipids and
oils from feeds to determine their Crude Fat content.
digesta: digested and undigested feed residues found in the
digestive tract.
digestibility: the potential for a feed ingredient or component
to be digested as it passes through the digestive tract.
Digestible Energy: the difference between the Gross Energy
consumed and the fecal energy excreted for a particular
feed component is properly called Apparent Digestible
Energy; true Digestible Energy also accounts for the
contribution to fecal energy of endogenous losses such as
secretions and cell sloughing from the digestive tract.
diuretic: a substance that causes urination to increase.
Glossary of Terms
(continued)
Dry Matter Intake: the amount consumed of the moisture-free
portion of a diet.
duodenum: the first segment of the small intestine after the
stomach (abomasum in ruminants).
dwarfism: the condition of being abnormally smaller than the
average size for the species.
effective fibre: the amount or proportion of fibre in the diet
which is capable of provoking chewing and salivation;
usually related to the amount or proportion of long
forage particles; there is currently no strictly quantitative
definition.
emulsion: A mixture of two normally unmixable liquids (e.g., oil
and water) in which one exists as tiny, suspended particles
within the other.
epithelial cells: the layer of cells on the surface of skin and
mucous membranes.
ergot: a fungal disease of Rye and other cereals that replaces
the grain kernal with a long, dark, horny body.
eructate: to expel gas from the stomach via the mouth.
esophagus: the tube-like upper portion of the digestive tract
which carries food and fluid from the mouth to the
stomach and boluses of digesta back to the mouth for
rumination (cud-chewng).
essential amino acid: one of 10 amino acids which cannot be
synthesized by mammalian tissues, they are arginine,
histidine, isoleucine, leucine, lysine, methionine,
phenylalanine, threonine, tryptophan and valine.
essential oil: a vegetable oil having the distinct odour of the
plant from which it was derived (e.g., peppermint oil).
ethyl alcohol (ethanol): an organic alcohol produced from the
aerobic fermentation of starch or other organic matter;
the intoxicating ingredient in beer, spirits and wine.
fat: a lipid which is a solid at 20°C, suggesting the presence of
a low proportion of short chain fatty acids and a high
proportion of saturated long chain fatty acids.
fat soluble vitamins: a group of vitamins which are insoluble in
water, soluble in organic solvents and stored in body fat,
including vitamins A, D, E amd K.
fatty acid: an organic compound with an acid group (HOC–) on
one end and hydrogen (H) atoms attached to a backbone
of carbon (C) atoms; when 2 H atoms are attached to each
non-terminal C, the fatty acid is saturated; when pairs of H
atoms are missing from adjacent C atoms, it is unsaturated.
FFA
Glossary of Terms
(continued)
18:1
Oxygen
Carbon
Hydrogen
Missing Hydrogen
fatty acid ester: an organic compound formed by combining a
fatty acid with an organic alcohol, most commonly
glycerol.
fibre: the parts of a plant whose cell walls contain cellulose,
hemicellulose and lignin.
fistula: a surgically implanted device which provides an open
connection from the exterior of the animal to an internal
organ; fistulas (in some cases called cannulas) are
commonly installed to facilitate sample collections during
experimental procedures.
free fatty acid: a fatty acid whose acid group is not linked to
another compound (e.g., esterified to an organic alcohol);
when body fat (adipose tissue) is mobilized, it enters the
bloodstream as free fatty acids.
fructose: a 6-carbon sugar commonly found in fruit.
fungi: a group of rumen micro-organisms that absorb food in
solution directly through their cell walls and reproduce
through spores (e.g., yeasts and moulds)
galactose: a 6-carbon sugar imilar to glucose.
germ or germ oil: products made from the developing cells of a
seed (e.g. , Wheat germ is the embryo of Wheat seed).
gestation: pregnancy.
glucose: a 6-carbon sugar found in fruits, animal tissues and
animal fluids; glucose is about half as sweet as sucrose
(table sugar); also called dextrose.
glyceride: a lipid which consists of a glycerol molecule with
one, two or three fatty acids attached to it; these are called
monoglycerides, diglycerides, and triglycerides, respectively;
fat is stored in the animal body in the form of glycerides.
C
O
H
C OH
H
C OH
Fatty Acid
H
Monoglyceride
Gly
cer
ol
H
H
H
H
C
O
Fatty Acid
H
C
O
Fatty Acid
H
C OH
H
Diglyceride
Gly
cer
ol
H
Gly
cer
ol
Glossary of Terms
(continued)
H
C
O
Fatty Acid
H
C
O
Fatty Acid
H
C
O
Fatty Acid
H
Triglyceride
glycerol: a colourless, odourless liquid alcohol; sweet tasting
and syrupy; obtained from natural lipids.
glycoprotein: a carbohydrate and protein combination.
goitre: enlargement of the thyroid gland causing a swelling of
the neck just below the lower jaw.
grass tetany: a metabolic disorder causing nervous signs and
resulting from a low blood Magnesium concentration
(hypomagnesemia); usually a result of being fed on young
pastures high in sodium and potassium.
green chop: fresh forage which is ‘cut and carried’ to animals.
Glossary of Terms
(continued)
green feed: in some areas, green feed refers to green chop; on
the prairies, green feed usually refers to a cereal crop
harvested for hay.
Gross Energy: the total amount of heat (calories) produced
from the combustion of feed in an atmosphere of pure
oxygen.
hay: forage stored with a moisture level below 20%.
haylage: a hay-crop stored as silage with a moisture level
typically between 30 and 60%.
heat of production: the heat produced as the products of
digestion are metabolized.
hemicellulose: a complex, branched-chain polysaccharide
composed of subunits including a number of different
simple sugars; closely associated with lignin in the plant
cell wall.
hemoglobin: the protein responsible for conveying oxygen, via
red blood cells, to organs and tissues throughout the body.
hydrochloric acid (HCl): the acid secreted from mucosal cells
lining the abomasum; responsible for lowering the pH of
digesta entering the small intestine.
hydrogenation: the addition of hydrogen atoms to
unsaturated fatty acids to increase their degree of
saturation; vegetable oils which are liquid at 20°C are
hydrogenated to produce solid margarine.
hydrolysis: chemical breakdown involving the addition of
water (H2O).
hypocalcemia: low blood Calcium concentration; Milk Fever
may occur when blood Calcium concentration falls below 7
mg/dl (milligrams per decilitre).
hypogonadism: decreased function of the gonads; retardation
of sexual development and growth.
Glossary of Terms
(continued)
hypomagnesemia: low blood Magnesium concentration;
Grass Tetany may occur when blood Magnesium
concentration falls below 1 mg/dl (milligrams per decilitre).
ileum: the third section of the small intestine, draining into the
large intestine.
immunity: resistance to infection by disease-causing
(pathogenic) organisms.
immunoglobulin: a blood protein having antibody activity,
transferred from dam to calf via colostrum.
inductively coupled plasma spectrophotometry: a laboratory
method used to measure very low concentrations of
minerals.
intramuscular: refers to the injection of drugs or nutrients into
muscular tissue.
intrauterine: refers to the administration of drugs into the
body of the uterus.
intravenous: refers to the injection of drugs or nutrients
directly into the bloodstream through a vein.
ion: an atom or molecule having either a positive charge
(cation) or a negative charge (anion).
jejunum: the middle segment of the small intestine, between
duodenum and ileum.
laminae: the ridged area of attachment between the horn-like
walls of the hoof and the underlying tissues.
laminitis: inflammation of the laminae of the hoof.
lignified nitrogen: represents protein which has become
bound to lignin through heating; such ‘heat-damaged’
protein is indigestible.
lipid: an organic compound (fat or oil) primarily composed of
free fatty acids and/or glycerol esters of fatty acids—
mono-, di- and triglycerides.
Glossary of Terms
(continued)
macromineral: a mineral element required in relative large
amounts by animals (e.g., Sodium, Chlorine, Calcium).
metabolic disorder: non-infectious disease resulting from
abnormal biochemical processes in the body (e.g., Ketosis,
Milk Fever).
metabolism: the biochemical process which take place in
living organisms.
Metabolizable Energy: energy available for biochemical
processes within the animal.
Metabolizable Protein: true protein available to the animal for
metabolism.
metalloenzyme: an enzyme containing a metal ion.
microbial protein: cellular protein produced by the bacteria,
fungi and protozoa that inhabit the rumen; as microbial
cells are carried out of the rumen and into the lower
digestive tract, microbial protein becomes available for
digestion and absorption by the host animal.
micromineral: a mineral element required in relative small
amounts by animals (e.g., Copper, Selenium, Zinc).
Milk Fever: a metabolic disorder resulting from low levels of
calcium available in the blood; signs of the disease include:
staggering gait, paralysis, and coma.
mineral: an inorganic element (e.g., Calcium, Sodium, Sulphur).
mycotoxin: a toxic chemical produced by mould.
myoglobin: a muscle protein which is responsible for taking up
the oxygen required for muscle contraction.
Net Energy: energy available to support maintenance, growth
and milk production.
Net Protein: true protein and amino acids available to
support maintenance, growth and milk production.
Glossary of Terms
(continued)
nitrate (NO3–): the primary form of nitrogen absorbed by plants
from soil; forages harvested under conditions where they
have accumulated excess nitrate (frost, drought, heavy
application of N fertilizer or manure) can be toxic to animals.
non-essential amino acid: one of 10 amino acids which can be
synthesized by mammalian tissues, they are alanine,
aspartic acid, cysteine, cystine, glutamic acid, glycine,
hydroxyproline, proline, serine and tyrosine.
nucleic acid: a complex molecule which encodes genetic
information in a long chain consisting of unique sequences
of the nucleotides adenine, guanine, cytosine, thymine and
uracil; nucleotides contain phosphorus as well as carbon,
hydrogen, nitrogen and oxygen.
oil: a lipid which is liquid at 20°C, suggesting the presence of a
high proportion of short chain and/or long chain
unsaturated fatty acids.
omasum: the third compartment of the ruminant stomach;
responsible for extracting water from digesta and
propelling digesta from the rumen and reticulum into the
abomasum.
organic: refers to chemical compounds primarily composed of
carbon, hydrogen and oxygen.
organic acid: an organic compound with an acid group (OCO–)
at one end.
osteomalacia: softening of mature bone due to deficiency of
Calcium and Phosphorus mineralization when bone cells
are replaced as part of normal turnover.
osteoporosis: decreased density of bones.
papillae: short projections lining the wall of the rumen which
increase the surface area for absorption of nutrients.
parity: the number of times a cow has calved; primiparous
cows have calved once, multiparous cows have calved
more than once.
Glossary of Terms
(continued)
passive immunity: resistance to infection acquired through the
intake of antibodies in colostrum or other medium; see
also active immunity.
pectin: a polysaccharide, rich in galacturonic acid, which
cements together the other compounds in the plant cell
wall (cellulose, hemicellulose, lignin).
pelleting: a type of feed processing where feeds are ground,
treated with steam and forced through a small diameter
die at high pressure.
pentosans: a class of polysaccharides whose subunits are five
carbon sugars.
pentose: a five carbon sugar.
peptide: a short chain of amino acids, usually no more than 10
amino acids long; a polypeptide is a longer single chain.
perennial forage: a forage species having a life span of greater
than two years.
phospholipid: a triglyceride that has a phosphorous-containing
compound bound to it in place of one of the 3 fatty acids.
physical fibre: structured roughage; plant material that, when
consumed, provokes chewing and salivation.
polysaccharide: a carbohydrate composed of long straight
and/or branched chains of simple sugars (e.g., cellulose,
pectins, pentosans).
propionic acid: one of the primary volatile fatty acids
produced by the microbial fermentation of feeds in the
rumen and in silage; chemical formula - C3H6O2.
Diagram of porcine insulin
showing the 3-dimensional
relationships of its six chains.
protein: a large molecule composed of one or more chains of
amino acids linked in a specific order through peptide
bonds; proteins are required for the structure, function,
and regulation of the bodys cells, tissues, and organs; each
protein has unique functions; examples are hormones (see
diagram of insulin on left), enzymes, and antibodies.
Glossary of Terms
(continued)
protozoa: a single-celled micro-organism having a membranebound, structurally discrete nucleus and other subcellular
compartments which are absent in bacteria.
provitamin: a compound that an organism can transform into
a vitamin (e.g., carotene gives rise to Vitamin A).
resin: a non-volatile, solid or semi-solid organic plant exudate.
reticulum: the first section of the ruminant stomach marked by
the distinctive ‘honeycomb’ appearance of its inside
surface (see photo on left).
ribonucleic acid (RNA): the nucleic acid responsible for
transfering the genetic information encoded in DNA to the
cell machinery responsible for synthesizing proteins.
rickets: softening of the bones due to a deficiency of Vitamin D
or calcium.
The inside surface of rumen
(upper) and reticulum (lower)
in the stomach of a young calf.
rumen: the second and largest section of the ruminant
stomach, home to a varied population of bacteria, fungi
and protozoa which digest feed in an anaerobic (without
oxygen) environment.
Rumen Acidosis: a metabolic disorder that occurs when the
cow is unable to buffer the acids produced by rumen
fermentation; rumen digesta become more acidic, rumen
pH dropping below 5.6.
Rumen Degradable Protein (RDP): Crude Protein in feed which
has the potential to be broken down by rumen microbes.
Rumen Undegradable Protein (RUP): Crude Protein in feed
which has the potential to escape degradation by rumen
microbes, passing to the lower digestive tract where it may
be digested or excreted; also referred to as bypass or
escape protein.
salivary glands: glands in the mouth responsible for the
secretion of saliva which protects and coats the digestive
system, buffers rumen contents, dissolves nutrients for
absorption and carries feed down the digestive tract.
Glossary of Terms
(continued)
saturated: refers to fatty acids in which all carbon atoms carry
a complete complement of hydrogen atoms.
silage: a forage crop stored at a moisture level normally in the
30-60% range.
silica: silicon dioxide (SiO2); appearing naturally as quartz,
sand and flint.
Sodium Lauryl Sulphate: a detergent used in the determination
of Neutral Detergent Fibre.
starch: a white, tasteless, solid carbohydrate composed of
chains of glucose subunits; found in the kernel of seeds
and other plant parts.
steroid: a chemical sustance containing the core structure of
cholesterol (e.g., hormones such as estrogen and cortisol,
vitamin D).
subcutaneous: under the skin.
sugar: simple carbohydrates, including monosaccharides such
as glucose (blood sugar) and fructose and disaccharides
such as lactose (milk sugar) and sucrose (table sugar).
tannin: chemical compounds which impart a bitter taste to
plants and are thought to provide protection from insects
and animals; tannins bind to, and may reduce digestibility
of proteins.
temper rolling: rolling of grain after soaking in water; reduces
shattering of grain kernels, resulting in fewer small starch
particles which are degraded very rapidly by rumen
microbes.
thyroxine: a hormone produced by the thyroid gland which
controls basal meatabolic rate.
thyroid gland: a ductless gland found on either side of the
neck, responsible for the regulation of metabolism and
growth through secretion of the hormone thyroxine.
Glossary of Terms
(continued)
trace mineral: a mineral element required in relative small
amounts by animals (e.g., Copper, Selenium, Zinc).
transferase: an enzyme that facilitates the transfer of a
chemical group from one molecule to another.
transition milk: milk produced by the cow after colostrum but
before milk of normal composition is seen.
true protein: chemical compounds composed of chains of
amino acids linked through peptide bonds; used to
distinguish from Crude Protein.
tungstic acid (H2O4W): used to precipitate protein in the
determination of true protein.
unsaturated: refers to fatty acids in which hydrogen atoms are
missing from adjacent carbon atoms in the chain.
urea: a nitrogen-containing compound excreted in urine;
used in rations as a source of non-protein nitrogen.
urease: an enzyme produced by rumen bacteria which breaks
down (hydrolyses) urea to produce ammonia and carbon
dioxide.
variance: a statistical estimate of the amount of variation
within a group of measurements.
volatile fatty acids: short chain (2-5 carbons) fatty acids which
evaporate at 20ºC; the primary end-products of rumen
fermenation.
White Muscle Disease: a metabolic disease resulting from a
deficiency of selenium and/or Vitamin E; often seen in
calves of dams who were deficient in selenium or Vitamin E
in late gestation; signs include: weak, hard muscles and an
inability to stand or walk with a normal gait.
Feeds & Feeding 169
GC
GREEN
CERTIFICATE
CURRICULUM
DPP
TOC
Index
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
R
S
T
U
V
W
Y
Z
A
abomasum
definition .......................................................................................................... 153
accelerated calf feeding. See calves: feeding
acetic acid
definition .......................................................................................................... 153
from rumen fermentation ............................................................................ 89
acetoacetic acid ....................................................................................................... 143
acetone ....................................................................................................................... 143
Acid Detergent Fibre
and estimation of feed energy value ........................................................ 24
method of feed analysis ................................................................................ 24
Acid Detergent Fibre Nitrogen. See Acid Detergent Insoluble Nitrogen
Acid Detergent Fibre Protein. See Acid Detergent Insoluble Nitrogen
Acid Detergent Insoluble Nitrogen
as estimate of heat-damaged protein ...................................................... 34
method of feed analysis ................................................................................ 34
Acid Detergent Insoluble Protein ........................................................................ 34
acidosis. See Rumen Acidosis
ACP. See Adjusted Crude Protein
active immunity
definition .......................................................................................................... 153
active transport
definition .......................................................................................................... 153
ad libitum
definition .......................................................................................................... 153
additives. See feed additives
ADF. See Acid Detergent Fibre
ADF-N. See Acid Detergent Insoluble Nitrogen
ADF-P. See Acid Detergent Insoluble Nitrogen
ADIN. See Acid Detergent Insoluble Nitrogen
ADIP. See Acid Detergent Insoluble Protein
adipose tissue
definition .......................................................................................................... 153
Adjusted Crude Protein ........................................................................................... 34
ADP. See Apparent Digestible Protein
Alfalfa ............................................................................................................................. 55
illustration .......................................................................................................... 56
alkaline
definition .......................................................................................................... 153
amino acid
definition .......................................................................................................... 153
amino acids
essential .............................................................................................................. 94
limiting ................................................................................................................ 95
ammonia
definition .......................................................................................................... 153
ammonium salts
definition .......................................................................................................... 154
anemia
definition .......................................................................................................... 154
anestrus
definition .......................................................................................................... 154
anion
definition .......................................................................................................... 154
anionic supplements ............................................................................................... 80
See also Dietary Cation-Anion Balance
antibiotic
definition .......................................................................................................... 154
antibiotics
in milk replacer ............................................................................................... 107
antibody
definition .......................................................................................................... 154
antioxidant
definition .......................................................................................................... 154
Apparent Digestible Protein
requirements
of pre-weaned calves ............................................................... 109, 112
of weaned calves .................................................................................. 117
as fed ............................................................................................................................. 22
as is ................................................................................................................................. 22
as received ................................................................................................................... 22
ash
as estimate of feed mineral content ......................................................... 38
definition .......................................................................................................... 154
atomic absorption spectrophotometry
definition .......................................................................................................... 154
B
B-vitamins
definition .......................................................................................................... 155
in plants .............................................................................................................. 12
supplementation ............................................................................................. 79
bacterium
definition .......................................................................................................... 154
bagged feeds
sampling for analysis ...................................................................................... 18
Barley
as forage ............................................................................................................. 53
grain ..................................................................................................................... 58
grain processing .............................................................................................. 58
starch
rumen degradability ............................................................ 58, 59, 62
basic pH
definition .......................................................................................................... 154
Beet Pulp ...................................................................................................................... 67
molassed............................................................................................................. 67
beta-hydroxy butyric acid .................................................................................... 143
biotin .................................................................................................................. 99, 155
Birdsfoot Trefoil .......................................................................................................... 55
bloat ............................................................................................................................. 137
definition .......................................................................................................... 154
Blood Meal ................................................................................................................... 68
dietary limit ....................................................................................................... 68
body condition
and Displaced Abomasum ......................................................................... 139
in early lactation............................................................................................. 127
body reserves ........................................................................................................... 128
bolus
definition .......................................................................................................... 155
borate-phosphate buffer
definition .......................................................................................................... 155
Bovatec®
in calf starter .................................................................................................... 110
Bovine Virus Diarrhea ............................................................................................ 105
brew mash. See Brewer’s Grains
Brewer’s Grains ........................................................................................................... 69
dietary limit ....................................................................................................... 69
Bromegrass .................................................................................................................. 44
illustration .......................................................................................................... 46
buffering capacity
of silage ............................................................................................................... 40
buffers ........................................................................................................................... 80
in saliva ........................................................................................................ 86, 93
bulk density
of grain ................................................................................................................ 41
effect of processing ............................................................................... 43
bushel
definition .......................................................................................................... 155
bushel weight
of grain ................................................................................................................ 41
butyric acid
definition .......................................................................................................... 155
from rumen fermentation ............................................................................ 89
bypass protein. See Rumen Undegradable Protein
C
Ca. See Calcium
Calcium
blood concentration
and Grass Tetany .................................................................................. 142
and Milk Fever ....................................................................................... 144
metabolism
at calving ................................................................................................. 144
requirements
of dry cows ............................................................................................. 133
of springing heifers ............................................................................. 121
of weaned calves .................................................................................. 118
role in animal health ..................................................................................... 135
role in nutrition ................................................................................................ 96
signs of deficiency ........................................................................................... 96
calf starter .................................................................................................................. 110
intake, and weaning ...................................................................................... 115
calorie
definition .......................................................................................................... 155
calves
feeding
from weaning to breeding................................................................ 116
pre-weaning programs ...................................................................... 111
weaning ............................................................................................................ 115
Canola
meal ...................................................................................................................... 70
oil
feeding ....................................................................................................... 73
for dust control in feeds ....................................................................... 73
seed ...................................................................................................................... 63
dietary limit .............................................................................................. 63
fat content ................................................................................................ 63
procesing .................................................................................................. 63
carbohydrate reserves
in plants ................................................................................................................. 7
carbohydrates
definition .......................................................................................................... 155
digestion ............................................................................................................. 89
in plants ................................................................................................................. 7
synthesis in plant growth ................................................................................6
carbon dioxide
definition .......................................................................................................... 155
role in plant growth ...........................................................................................6
carotene
definition .......................................................................................................... 155
in plants .............................................................................................................. 12
carotenoid
definition .......................................................................................................... 155
cation
definition .......................................................................................................... 156
cellulose
definition .......................................................................................................... 156
in plants ................................................................................................................. 7
cetyl trimethyl ammonium bromide
definition .......................................................................................................... 156
in Acid Detergent Fibre analysis ................................................................. 24
chemical fibre ............................................................................................................. 42
definition .......................................................................................................... 156
chewing
and salivation ............................................................................................ 86, 93
role of structured roughage ........................................................................ 42
Chlorine
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 96
signs of deficiency ........................................................................................... 96
chlorophyll
and plant growth ................................................................................................ 6
definition .......................................................................................................... 156
choline ............................................................................................................... 99, 155
Cicer Milkvetch ........................................................................................................... 55
Cl. See Chlorine
close-up period ........................................................................................................ 132
CNCPS. See Cornell Net Carbohydrate and Protein System
Co. See Cobalt
Cobalt
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
coccidia ....................................................................................................................... 110
Coccidiosis
definition .......................................................................................................... 156
coccidiostats ............................................................................................................... 80
See also Deccox®, Bovatec®, Rumensin®
definition .......................................................................................................... 156
in calf starter .................................................................................................... 110
coenzyme
definition .......................................................................................................... 156
colorimetry
definition .......................................................................................................... 156
colostrum ................................................................................................................... 104
commodity sheds ..................................................................................................... 85
compensatory growth ........................................................................................... 111
definition .......................................................................................................... 156
computer grain feeding ........................................................................................ 122
concentrates
definition .......................................................................................................... 156
sampling for analysis ...................................................................................... 16
storage ................................................................................................................ 85
condition score ........................................................................................................ 128
method ............................................................................................................. 129
Copper
requirements
of dry cows ............................................................................................. 133
role in animal health ..................................................................................... 135
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
coring tool
definition .......................................................................................................... 156
Corn
as silage ............................................................................................................... 53
distiller's grains. See Distiller’s Grains
gluten feed ......................................................................................................... 71
gluten meal........................................................................................................ 71
dietary limit .............................................................................................. 71
grain ..................................................................................................................... 59
processing ................................................................................................ 59
starch
rumen degradability ............................................................ 58, 59, 62
Cornell Net Carbohydrate and Protein System
and effective NDF ............................................................................................ 25
and non-structural carbohydrates ............................................................. 26
definition .......................................................................................................... 157
corticosteroid
definition .......................................................................................................... 157
cows
feeding
dry ............................................................................................................. 132
lactating .................................................................................................. 122
CP. See Crude Protein
Crude Fat
method of feed analysis ................................................................................ 37
Crude Protein
definition .......................................................................................................... 157
fractions .............................................................................................................. 32
method of feed analysis ................................................................................ 31
requirements
of early lactation cows........................................................................ 130
of mid lactation cows ......................................................................... 131
of pre-weaned calves ............................................................... 109, 112
of springing heifers ............................................................................. 121
of weaned calves ....................................................................... 117, 118
Cu. See Copper
cutin
definition .......................................................................................................... 157
D
DCAB. See Dietary Cation-Anion Balance
DE. See Digestible Energy
Deccox®
in calf starter .................................................................................................... 110
degradability
definition .......................................................................................................... 157
dermatitis
definition .......................................................................................................... 157
detergent
definition .......................................................................................................... 157
Dietary Cation-Anion Balance
for prevention of Milk Fever ....................................................................... 144
diethyl ether
definition .......................................................................................................... 157
in Crude Fat analysis ....................................................................................... 37
digesta
definition .......................................................................................................... 157
digestibility
definition .......................................................................................................... 157
Digestible Energy ...................................................................................................... 92
definition .......................................................................................................... 157
requirements
of pre-weaned calves ............................................................... 109, 112
of weaned calves .................................................................................. 117
values of feeds
calculation from Net Energy for Lactation .................................... 27
digestive system ........................................................................................................ 86
Displaced Abomasum ........................................................................................... 138
effect of condition score ............................................................................. 140
Distiller’s Grains .......................................................................................................... 72
with solubles ..................................................................................................... 72
diuretic
definition .......................................................................................................... 157
DM. See Dry Matter
DMI. See Dry Matter Intake
DNA. See nucleic acid
dry basis ....................................................................................................................... 22
dry cows. See cows: dry
Dry Matter
method for feed analysis ............................................................................... 22
Dry Matter Intake
decrease pre-partum.................................................................................... 132
and Displaced Abomasum ............................................................... 138
and Fatty Liver Syndrome ................................................................. 141
and Ketosis ............................................................................................. 143
definition .......................................................................................................... 158
effect of stage of lactation ............................................................... 126, 127
in calculation of Relative Feed Quality ..................................................... 30
of lactating cows ............................................................................................ 127
dry period
optimum length ............................................................................................. 132
dry result ...................................................................................................................... 22
duodenum
definition .......................................................................................................... 158
dwarfism
definition .......................................................................................................... 158
Dystocia
and Displaced Abomasum ......................................................................... 138
E
E. coli ............................................................................................................................ 105
effective fibre
definition .......................................................................................................... 158
emulsion
definition .......................................................................................................... 158
energy
balance
in lactation.............................................................................................. 127
digestible. See Digestible Energy
gross. See Gross Energy
metabolizable. See Metabolizable Energy
net. See Net Energy, Net Energy for Gain, Net Energy for Lactation,
Net Energy for Maintenance
role in animal health ..................................................................................... 134
role in nutrition ................................................................................................ 92
unit conversions ............................................................................................... 27
table .......................................................................................................... 152
values of feeds
estimation from Acid Detergent Fibre ........................... 24, 27, 28
epithelial cells
definition .......................................................................................................... 158
ergot
definition .......................................................................................................... 158
in rye grain ......................................................................................................... 61
eructate
definition .......................................................................................................... 158
esophagus
definition .......................................................................................................... 158
essential amino acid
definition .......................................................................................................... 158
essential oil
definition .......................................................................................................... 158
ethanol
definition .......................................................................................................... 158
ether extract ................................................................................................................ 37
ethyl alcohol
definition .......................................................................................................... 158
F
fat
bypass .................................................................................................................. 73
definition .......................................................................................................... 159
supplementation ..................................................................................... 73, 90
dietary limit .............................................................................................. 74
Fat Cow Syndrome .................................................................................................. 140
fat soluble vitamins
definition .......................................................................................................... 159
fatty acid
definition .......................................................................................................... 159
fatty acid ester
definition .......................................................................................................... 159
fatty liver
and Displaced Abomasum ......................................................................... 139
Fatty Liver Syndrome ............................................................................................. 141
Fe. See Iron: role in nutrition
feather meal ................................................................................................................ 75
dietary limit ....................................................................................................... 75
feed
additives ............................................................................................................. 80
analysis ................................................................................................................ 19
by NIR ......................................................................................................... 21
by wet chemistry .................................................................................... 21
report interpretation ............................................................................ 19
table .......................................................................................................... 149
digestion ............................................................................................................. 86
sampling ............................................................................................................. 13
hay ............................................................................................................... 14
silage .......................................................................................................... 15
feed intake. See Dry Matter Intake
Feedlot (grain) Bloat. See bloat
fetus
growth ............................................................................................................... 132
growth during last trimester...................................................................... 119
fibre
and rumen mat ................................................................................................. 93
definition .......................................................................................................... 159
role in animal health ..................................................................................... 134
role in nutrition ........................................................................................ 42, 93
fish meal ....................................................................................................................... 76
dietary limit ....................................................................................................... 76
palatability ......................................................................................................... 76
fistula
definition .......................................................................................................... 159
Flaxseed ........................................................................................................................ 64
dietary limit ....................................................................................................... 64
feeding effect on milk fat .............................................................................. 64
oil content .......................................................................................................... 64
folic acid ............................................................................................................ 99, 155
foo-foo dust................................................................................................................. 80
forage
grain crop ........................................................................................................... 53
legume. See legume forages
free fatty acid
definition .......................................................................................................... 159
Free-gas Bloat. See bloat
frothy bloat. See bloat
fructose
definition .......................................................................................................... 159
in plants ................................................................................................................. 7
fungi ............................................................................................................................. 160
G
galactose
definition .......................................................................................................... 160
in plants ................................................................................................................. 7
germ
definition .......................................................................................................... 160
germ oil
definition .......................................................................................................... 160
gestation
definition .......................................................................................................... 160
glucose
blood concentration
in Ketosis ................................................................................................. 143
definition .......................................................................................................... 160
in plants ................................................................................................................. 7
glyceride
definition .......................................................................................................... 160
glycerol
definition .......................................................................................................... 160
glycoprotein
definition .......................................................................................................... 160
goitre
definition .......................................................................................................... 160
grain
crops..................................................................................................................... 53
See also Barley, Corn, Oats, Rye, Triticale, Wheat
processing .......................................................................................................... 43
sampling for analysis ...................................................................................... 16
grain bins ..................................................................................................................... 85
Gramineae ................................................................................................................... 53
Grass Tetany .............................................................................................................. 142
definition .......................................................................................................... 160
grasses
annual .................................................................................................................. 52
perennial............................................................................................................. 44
Bromegrass .............................................................................................. 44
Orchardgrass ........................................................................................... 44
Perennial Ryegrass ................................................................................. 45
Reed Canarygrass................................................................................... 45
Tall Fescue................................................................................................. 45
Timothy ..................................................................................................... 45
Wheatgrass ............................................................................................... 45
green chop
definition .......................................................................................................... 160
green feed
definition .......................................................................................................... 161
Gross Energy ............................................................................................................... 92
definition .......................................................................................................... 161
growth
accelerated, of calves .................................................................................... 106
curves for US Holsteins ................................................................................ 102
monitoring in heifers .................................................................................... 103
of calves ............................................................................................................ 111
from weaning to breeding................................................................ 116
of heifers
during pregnancy ................................................................................ 119
target for heifers
at breeding ............................................................................................. 119
targets for calves and heifers .......................................................... 102, 116
H
hay
definition .......................................................................................................... 161
feeding to calves ............................................................................................ 113
moisture level ................................................................................................... 81
sampling for analysis ...................................................................................... 14
storage ................................................................................................................ 81
haylage
definition .......................................................................................................... 161
health
effect of nutrition ........................................................................................... 134
heat damage
in silage ............................................................................................................... 34
heat of production
definition .......................................................................................................... 161
Heat-damaged Protein. See Acid Detergent Insoluble Nitrogen
heifers
feeding
after breeding ....................................................................................... 119
pre-puberty ............................................................................................ 116
Rumensin® ............................................................................................. 116
springing
management ......................................................................................... 120
hemicellulose
definition .......................................................................................................... 161
in plants ................................................................................................................. 7
hemoglobin
definition .......................................................................................................... 161
hydrochloric acid
definition .......................................................................................................... 161
hydrogenation
definition .......................................................................................................... 161
hydrolysis
definition .......................................................................................................... 161
hypocalcemia
definition .......................................................................................................... 161
hypogonadism
definition .......................................................................................................... 161
hypomagnesemia
definition .......................................................................................................... 162
Hypomagnesemic Tetany. See Grass Tetany
I
I. See Iodine
ileum
definition .......................................................................................................... 162
immunity
definition .......................................................................................................... 162
immunoglobulin
definition .......................................................................................................... 162
inductively coupled plasma spectrophotometry
definition .......................................................................................................... 162
intake. See Dry Matter Intake
intramuscular
definition .......................................................................................................... 162
intrauterine
definition .......................................................................................................... 162
intravenous
definition .......................................................................................................... 162
Iodine
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
ion
definition .......................................................................................................... 162
ionophores .................................................................................................................. 80
Iron
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
Italian Ryegrass .......................................................................................................... 52
J
jejunum
definition .......................................................................................................... 162
Johne’s Disease ........................................................................................................ 105
K
K. See Potassium
Ketosis ......................................................................................................................... 143
and Displaced Abomasum ......................................................................... 138
effect of condition score ............................................................................. 140
Kjeldahl
method of feed analysis ....................................................... 31, 32, 33, 35
Koster Crop Tester ..................................................................................................... 22
L
lactating cows. See cows: lactating
lactation curve ......................................................................................................... 126
laminae
definition .......................................................................................................... 162
laminitis ...................................................................................................................... 136
and Displaced Abomasum ......................................................................... 139
definition .......................................................................................................... 162
LDA. See Displaced Abomasum
legume forages .......................................................................................................... 54
Alfalfa ................................................................................................................... 55
and bloat ............................................................................................................ 54
Birdsfoot Trefoil ................................................................................................ 55
Cicer Milkvetch ................................................................................................. 55
mineral levels .................................................................................................... 54
Red Clover .......................................................................................................... 55
lignified nitrogen
definition .......................................................................................................... 162
lignin ................................................................................................................................. 8
in plants ................................................................................................................. 7
lipids
definition .......................................................................................................... 162
digestion ............................................................................................................. 90
in plants ................................................................................................................. 9
M
macromineral
definition .......................................................................................................... 163
macrominerals
in plants .............................................................................................................. 11
Magnesium
and chlorophyll ................................................................................................ 11
blood concentration
in Grass Tetany ...................................................................................... 142
requirements
of dry cows ............................................................................................. 133
role in animal health ..................................................................................... 135
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
mammary gland
involution ......................................................................................................... 132
swelling, in Udder Edema ........................................................................... 147
Manganese
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 98
signs of deficiency ........................................................................................... 98
mature shrunk body weight ................................................................................ 102
of heifers
at breeding ............................................................................................. 119
ME. See Metabolizable Energy
Megalac® ...................................................................................................................... 73
metabolic disorders
definition .......................................................................................................... 163
effect of condition score .................................................................. 128, 140
effect of low pre-partum DMI.................................................................... 132
metabolism
definition .......................................................................................................... 163
Metabolizable Energy .............................................................................................. 92
definition .......................................................................................................... 163
reqirements
of weaned calves ....................................................................... 117, 118
requirements
of pre-weaned calves ............................................................... 109, 112
of springing heifers ............................................................................. 121
values of feeds
calculation from Net Energy for Lactation .................................... 27
Metabolizable Protein ............................................................................................. 95
definition .......................................................................................................... 163
requirements
of dry cows ............................................................................................. 133
metalloenzyme
definition .......................................................................................................... 163
Metritis
and Displaced Abomasum ......................................................................... 138
Mg. See Magnesium
microbial protein
definition .......................................................................................................... 163
microminerals
definition .......................................................................................................... 163
in plants .............................................................................................................. 11
role in animal health ..................................................................................... 135
microwave oven
for feed Dry Matter testing ................................................................... 22, 23
milk
consumption by calves ................................................................................ 106
feeding to calves ............................................................................................ 105
hospital ............................................................................................................. 107
for calves ................................................................................................. 105
replacer ............................................................................................................. 107
feeding rate ............................................................................................ 108
Milk Fever ................................................................................................................... 144
and Displaced Abomasum ......................................................................... 138
definition .......................................................................................................... 163
effect of condition score ............................................................................. 140
minerals
definition .......................................................................................................... 163
feed analysis by NIR ................................................................................ 21, 38
method of feed analysis ................................................................................ 38
premixes ............................................................................................................. 78
role in nutrition ................................................................................................ 96
supplemental .................................................................................................... 78
ad libitum (free choice) feeding ........................................................ 78
uptake by plants ........................................................................................ 6, 11
Mn. See Manganese
moisture
method for feed analysis ............................................................................... 22
MP. See Metabolizable Protein
MSBW. See mature shrunk body weight
Mycoplasma .............................................................................................................. 105
mycotoxin
definition .......................................................................................................... 163
myoglobin
definition .......................................................................................................... 163
myoinositol....................................................................................................... 99, 155
N
Na. See Sodium
NDF. See Neutral Detergent Fibre
NDIN. See Neutral Detergent Insoluble Nitrogen
NDIP. See Neutral Detergent Insoluble Protein
Near Infrared Reflectance Spectroscopy........................................................... 21
for mineral analysis ......................................................................................... 38
NEG. See Net Energy for Gain
negative energy balance ...................................................................................... 140
NEM. See Net Energy for Maintenance
Net Energy ................................................................................................................... 92
definition .......................................................................................................... 163
Net Energy for Gain .................................................................................................. 92
requirements
of pre-weaned calves ............................................................... 109, 112
of springing heifers ............................................................................. 121
of weaned calves ....................................................................... 117, 118
values of feeds
calculation from Metabolizable Energy ......................................... 27
Net Energy for Lactation ......................................................................................... 92
requirements
of dry cows ............................................................................................. 133
of early lactation cows........................................................................ 130
of mid lactation cows ......................................................................... 131
values of feeds
estimation from Acid Detergent Fibre ............................................ 27
Net Energy for Maintenance ................................................................................. 92
requirements
of pre-weaned calves ............................................................... 109, 112
of springing heifers ............................................................................. 121
of weaned calves ....................................................................... 117, 118
values of feeds
calculation from Metabolizable Energy ......................................... 27
Net Protein
definition .......................................................................................................... 163
Neutral Detergent Fibre
digestibility
and milk production ............................................................................. 30
method of feed analysis ................................................................................ 25
requirements
of dry cows ............................................................................................. 133
Neutral Detergent Insoluble Nitrogen
method of feed analysis ................................................................................ 35
Neutral Detergent Insoluble Protein .................................................................. 35
in Cornell Net Carbohydrate and Protein System................................. 35
rumen degradability ....................................................................................... 35
NFC. See Non-fibre Carbohydrates
niacin .................................................................................................................. 99, 155
NIR. See Near Infrared Reflectance Spectroscopy
NIRS. See Near Infrared Reflectance Spectroscopy
nitrates
and nitrogen fixation ..................................................................................... 10
definition .......................................................................................................... 164
role in plant growth ...........................................................................................6
nitrogen fixation
in legume forages ............................................................................................ 10
non-essential amino acid
definition .......................................................................................................... 164
Non-fibre Carbohydrates
and rumen acidosis ....................................................................................... 136
method of calculation ............................................................................ 26, 37
Non-protein Nitrogen
as fraction of Crude Protein ................................................................. 31, 32
method of feed analysis ................................................................................ 32
rumen degradability ............................................................................... 32, 36
Non-structural Carbohydrates
digestion in rumen .......................................................................................... 89
in plants ................................................................................................................. 7
method of calculation .................................................................................... 26
NPN. See Non-protein Nitrogen
NSC. See Non-structural Carbohydrates
nucleic acid
definition .......................................................................................................... 164
nutrient requirements
of dry cows ....................................................................................................... 133
of early lactation cows ................................................................................. 130
of mid lactation cows ................................................................................... 131
of pre-weaned calves ........................................................................ 109, 112
of springing heifers ....................................................................................... 121
of weaned calves ........................................................................................... 117
O
Oats
as forage ............................................................................................................. 53
grain ..................................................................................................................... 60
processing ................................................................................................ 60
oil
definition .......................................................................................................... 164
supplementation ..................................................................................... 73, 90
dietary limit .............................................................................................. 74
omasum
definition .......................................................................................................... 164
Orchardgrass ............................................................................................................... 44
illustration .......................................................................................................... 47
organic
definition .......................................................................................................... 164
organic acid
definition .......................................................................................................... 164
osteomalacia
definition .......................................................................................................... 164
osteoporosis
definition .......................................................................................................... 164
P
P. See Phosphorus
pantothenic acid ............................................................................................ 99, 155
papillae
definition .......................................................................................................... 164
para-aminobenzoic acid .............................................................................. 99, 155
parity
definition .......................................................................................................... 164
particle size
of forages ............................................................................................................ 42
and Displaced Abomasum ............................................................... 138
passive immunity
definition .......................................................................................................... 165
Pasteurella ................................................................................................................. 105
pasteurization
of hospital milk ............................................................................................... 105
Pea .................................................................................................................................. 66
varieties ............................................................................................................... 66
peak milk ......................................................................................................... 126, 128
pectins
definition .......................................................................................................... 165
in plants ................................................................................................................. 7
pelleting
definition .......................................................................................................... 165
Penn State Forage Particle Separator ................................................................. 42
pentosans
definition .......................................................................................................... 165
in plants ................................................................................................................. 7
pentose
definition .......................................................................................................... 165
in plants ................................................................................................................. 7
peptide
definition .......................................................................................................... 165
perennial forage
definition .......................................................................................................... 165
Perennial Ryegrass .................................................................................................... 45
illustration .......................................................................................................... 48
persistency ..................................................................................................... 126, 128
pH
of rumen digesta ............................................................................................. 89
in rumen acidosis ................................................................................. 136
of silage ............................................................................................................... 40
method of determination ................................................................... 40
phospholipid
definition .......................................................................................................... 165
Phosphorus
in plant protein ................................................................................................. 10
requirements
of dry cows ............................................................................................. 133
of springing heifers ............................................................................. 121
of weaned calves .................................................................................. 118
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
physical fibre ............................................................................................................... 42
definition .......................................................................................................... 165
placenta
structure in cow ............................................................................................. 146
polysaccharide
definition .......................................................................................................... 165
Potassium
in soil
and Grass Tetany .................................................................................. 142
in udder edema .............................................................................................. 147
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
processing index ....................................................................................................... 43
propionic acid
definition .......................................................................................................... 165
from rumen fermentation ............................................................................ 89
propylene glycol ........................................................................................................ 80
as Ketosis treatment ..................................................................................... 143
protein
definition .......................................................................................................... 165
digestion ............................................................................................................. 91
in plants .............................................................................................................. 10
metabolizable. See Metabolizable Protein
net. See Net Protein
role in animal health ..................................................................................... 134
role in nutrition ................................................................................................ 94
proteins
synthesis in plant growth ................................................................................6
protozoa
definition .......................................................................................................... 166
provitamin
definition .......................................................................................................... 166
pushing up
total mixed ration .......................................................................................... 125
R
Ration Formulation ................................................................................................. 148
RDP. See Rumen Degradable Protein
Red Clover .................................................................................................................... 55
illustration .......................................................................................................... 57
Reed Canarygrass ...................................................................................................... 45
Relative Feed Quality ............................................................................................... 30
Relative Feed Value ................................................................................................... 29
resin
definition .......................................................................................................... 166
Retained Placenta ................................................................................................... 146
and Displaced Abomasum ......................................................................... 138
effect of condition score ............................................................................. 140
reticulum
definition .......................................................................................................... 166
RFQ. See Relative Feed Quality
RFV. See Relative Feed Value
riboflavin ........................................................................................................... 99, 155
ribonucleic acid (RNA)
definition .......................................................................................................... 166
rickets
definition .......................................................................................................... 166
root reserves
in plants ................................................................................................................. 7
rumen
definition .......................................................................................................... 166
fermentation ..................................................................................................... 87
microbes ..................................................................................................... 86, 89
Rumen Acidosis ....................................................................................................... 136
and Displaced Abomasum ......................................................................... 139
definition .......................................................................................................... 166
Rumen Degradable Protein ................................................................................... 36
definition .......................................................................................................... 166
method of feed analysis ................................................................................ 36
requirements
of dry cows ............................................................................................. 133
of early lactation cows........................................................................ 130
of springing heifers ............................................................................. 121
of weaned calves .................................................................................. 118
requirements of mid lactation cows ............................................. 131
Rumen Undegradable Protein .............................................................................. 95
definition .......................................................................................................... 166
requirements
of dry cows ............................................................................................. 133
of early lactation cows........................................................................ 130
of mid lactation cows ......................................................................... 131
of springing heifers ............................................................................. 121
of weaned calves .................................................................................. 118
Rumensin®
in calf grower .................................................................................................. 116
in calf starter .................................................................................................... 110
in heifer ration ................................................................................................ 116
to reduce Ketosis incidence ....................................................................... 143
RUP. See Rumen Undegradable Protein
Rye
as pasture ........................................................................................................... 53
distiller's grains ................................................................................................. 72
grain ..................................................................................................................... 61
S
S. See Sulphur
salivary glands
definition .......................................................................................................... 166
salivation ...................................................................................................................... 86
role of structured roughage ........................................................................ 42
sampling
bulk concentrates ............................................................................................ 16
SARA. See Subacute Rumen Acidosis
saturated
definition .......................................................................................................... 167
Se. See Selenium
Selenium
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 98
signs of deficiency ........................................................................................... 98
silage
cereal.................................................................................................................... 44
definition .......................................................................................................... 167
effluent collection ........................................................................................... 84
grain-crop ........................................................................................................... 44
hay-crop .............................................................................................................. 44
legume ....................................................................................................... 54
sampling for analysis ...................................................................................... 15
storage ................................................................................................................ 82
silica
definition .......................................................................................................... 167
Sodium
in Udder Edema ............................................................................................. 147
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
Sodium Lauryl Sulphate
definition .......................................................................................................... 167
in Neutral Detergent Fibre analysis ........................................................... 25
Soluble Protein
method of feed analysis ................................................................................ 33
rumen degradability ............................................................................... 33, 36
sorting
of total mixed ration ..................................................................................... 124
Soy
meal ...................................................................................................................... 77
in calf starter .......................................................................................... 110
SP. See Soluble Protein
Spartan Dairy Ration Evaluator® ........................................................................ 148
starch
definition .......................................................................................................... 167
in grain kernel ...................................................................................................... 7
in plants ................................................................................................................. 7
starter. See calf starter
steroid
definition .......................................................................................................... 167
Structural Carbohydrates
digestion in rumen .......................................................................................... 89
in plants ................................................................................................................. 7
structured roughage ................................................................................................ 42
Subacute Rumen Acidosis.................................................................................... 136
See also Rumen Acidosis
subcutaneous
definition .......................................................................................................... 167
sugars
definition .......................................................................................................... 167
in plants ................................................................................................................. 7
Sulphur
in plant protein ................................................................................................. 10
requirements
of dry cows ............................................................................................. 133
role in nutrition ................................................................................................ 97
signs of deficiency ........................................................................................... 97
Sunflower
seed ...................................................................................................................... 65
dietary limit .............................................................................................. 65
oil content ................................................................................................ 65
T
Tall Fescue .................................................................................................................... 45
illustration .......................................................................................................... 49
tallow ............................................................................................................................. 73
tannin
definition .......................................................................................................... 167
target body weight ................................................................................................. 102
TBW. See target body weight
TDN. See Total Digestible Nutrients
temper rolling
definition .......................................................................................................... 167
thiamine ............................................................................................................ 99, 155
thyroid gland
definition .......................................................................................................... 167
thyroxine
definition .......................................................................................................... 167
Timothy ........................................................................................................................ 45
illustration .......................................................................................................... 50
TMR. See total mixed ration
Total Digestible Nutrients
requirements
of springing heifers ............................................................................. 121
of weaned calves .................................................................................. 118
values of feeds
calculation from Net Energy for Lactation .................................... 27
total mixed ration .................................................................................................... 124
for heifers
after breeding ....................................................................................... 119
at 6 months of age ............................................................................... 116
for lactating cows .......................................................................................... 122
trace minerals. See microminerals
transferase
definition .......................................................................................................... 168
transition milk
definition .......................................................................................................... 168
trichloroacetic acid
in True Protein analysis .................................................................................. 32
Triticale
as silage ............................................................................................................... 53
True Protein
as fraction of Crude Protein ......................................................................... 32
compared with Crude Protein ..................................................................... 31
definition .......................................................................................................... 168
separation from Non-protein Nitrogen ................................................... 32
tungstic acid
definition .......................................................................................................... 168
in True Protein analysis .................................................................................. 32
U
udder. See mammary gland
Udder Edema ............................................................................................................ 147
urea
definition .......................................................................................................... 168
urease
definition .......................................................................................................... 168
uterus
growth during last trimester...................................................................... 119
V
variance
definition .......................................................................................................... 168
VFA. See volatile fatty acids
vitamin A ...................................................................................................................... 99
requirements
of dry cows ............................................................................................. 133
of pre-weaned calves ............................................................... 109, 112
of weaned calves .................................................................................. 117
role in animal health ..................................................................................... 135
role in nutrition ................................................................................................ 99
signs of deficiency ........................................................................................... 99
supplementation ............................................................................................. 79
synthesis from carotene ................................................................................ 12
vitamin B1. See thiamine
vitamin B12 ...................................................................................................... 99, 155
vitamin B2. See riboflavin
vitamin B6 ......................................................................................................... 99, 155
vitamin C ...................................................................................................................... 99
role in animal health ..................................................................................... 135
vitamin D ...................................................................................................................... 99
requirements
of dry cows ............................................................................................. 133
role in nutrition .............................................................................................. 100
signs of deficiency ......................................................................................... 100
supplementation ............................................................................................. 79
vitamin E ....................................................................................................................... 99
requirements
of dry cows ............................................................................................. 133
role in animal health ..................................................................................... 135
role in nutrition .............................................................................................. 100
signs of deficiency ......................................................................................... 100
supplementation ............................................................................................. 79
vitamin K ...................................................................................................................... 99
vitamins
fat soluble ................................................................................................... 79, 99
in plants .............................................................................................................. 12
method of feed analysis ................................................................................ 39
role in animal health ..................................................................................... 135
role in nutrition ................................................................................................ 99
supplemental .................................................................................................... 79
water soluble ..................................................................................................... 99
volatile fatty acids
definition .......................................................................................................... 168
production in rumen ...................................................................................... 89
stimulation of rumen development ........................................................ 113
W
water
body content................................................................................................... 101
for calves ........................................................................................................... 110
role in nutrition .............................................................................................. 101
weaning. See calves: weaning
Wheat
as forage ............................................................................................................. 53
distiller's grains ................................................................................................. 72
grain ..................................................................................................................... 62
dietary limit .............................................................................................. 62
starch
rumen degradability ............................................................ 58, 59, 62
Wheatgrass .................................................................................................................. 45
illustration .......................................................................................................... 51
Y
yellow grease .............................................................................................................. 73
Z
Zinc
requirements
of dry cows ............................................................................................. 133
role in animal health ..................................................................................... 135
role in nutrition ................................................................................................ 98
signs of deficiency ........................................................................................... 98
Zn. See Zinc
Dairy Production Supervisor: Skill Training Curriculum
A
MANAGING
MILKING &
SANITATION
Monitor & manage
the milking equipment
system for proper
operation
A2 II
Develop & manage a
cleaning & sanitation
program for milk
equipment
A3 II
Develop a feeding
program & supervise
calf feeding
(0 - 3 months)
Ä
B1 II
Operate & manage
the preventative
health program for
calves
B2 II
Monitor calf health,
detect sickness &
disorders (as listed)
& take action
B3 II
Ä
Demonstrate a basic
knowledge of cattle
anatomy &
physiology
C1 II
Ä
Develop a herd health
& vaccination
program
Establish & maintain
a calving & maternity
area
Supervise the milking
routine
A1
B
MANAGING
CALF REARING
C
MANAGING
CATTLE HEALTH
C9
D
FEEDING THE
HERD
E
DAIRY
PRODUCTS
MARKETING
G
GENERAL
SUPERVISING
II
Ä
Ä
Judge & assess cattle
performance & select
animals for culling
E1
F
II
Demonstrate a basic
knowledge cattle
nutrition
D1
MANAGING
CATTLE
BREEDING
II
II
Ä
Develop a schedule &
routine & manage the
servicing of the milk
systems
A4 II
Supervise the
maintenance of milk
quality standards
Read, interpret &
demonstrate basic
knowledge of the
Dairy Code of Practice
C3 II
Ä
Demonstrate knowledge
of common respiratory
diseases & disorders &
treat a suspected case
C4 II
Demonstrate knowledge
of common digestive
diseases & disorders &
treat a suspected case
C5 II
Demonstrate knowledge
of common respiratory
diseases & disorders &
treat where possible
C6 II
Assess lab testing
options to diagnose
health problems &
take proper samples
C10 II
Set up & maintain a
multi-purpose cow
history record system
(health, breeding, etc)
C11 II
Manage the calving
program & assist
cows when calving
Develop & manage a
mastitis control
program
C12 II
C13 II
Diagnose minor
problems & carry out
basic foot trimming &
care
C14 II
Take a feed sample
for nutrient analysis &
interpret lab results
Perform a condition
scoring on a cow
Manage program &
supervise the feeding
of replacement cattle
(6 months - calving)
Ä
D4 II
Ä
Supervise the feeding
program & manage
the feeding of the
milking herd
Ä
D5 II
Ä
Perform AI and
manage the on-farm
storage of semen
Operate the DHI
program in the herd
C2
D2
Ä
II
II
Ä
Ä
Judge & select cows
& bulls for mating
E2
II
Ä
Demonstrate a basic
knowledge of milk
marketing, dairy
policy & pricing
F1 II
Ä
Manage the herd’s
production to
optimize quota
requirements
F2 II
Demonstrate use of
decision making and
problem solving
techniques
G1 II
Ä
Demonstrate effective
verbal & written
communication for
records, staff & public
G2 II
Ä
D3
II
Ä
Ä
Operate the herd
breeding program
E3
II
Ä
E4
II
Ä
A5
E5
II
II
Supervise the farm
facilities cleaning &
waste management
program
A6 II
II
Manage dry cow
health & feeding
C8
II
Supervise & manage
the operation of the
feeding equipment
Manage the pastue
grazing of cattle
D6
Develop & manage a
control program for
external & internal
parasites & pests
C7 II
Ä
D7
II
Ä
Ä
Manage the
marketing of cattle
Ä
F3
II
Demonstrate
supervisor’s time
management
competence
G3 II
Ä
Ä
Plan & manage farm
staff work schedule
Ä
G4
II
Ä
Ä
Supervise farm staff work
activities
G5
II
Ä
Ä
Conduct training of
farm staff
G6
II
Ä
Conduct production
meetings
Ä
G7
II
Ä
Ä