1. health and fitness
2. disease

Egyptian J. Anim. Prod. (2011) 48(1):77-85.
ANTIBODY RESPONSE IN EARLY HATCHED CHICKS AS
INFLUENCED BY VACCINATION AND DIFFERENT
MATERNAL ANTIBODY LEVELS
A. S. Ahmed
Department of Animal and Fish Production, College of Agriculture and Food
Science, King Faisal University, Saudi Arabia
SUMMARY
This study evaluated the antibody response to Newcastle disease (ND) and sheep
red blood cells (SRBC) of early hatched chicks as influenced by their maternal
immune capacity and early vaccination. Chicks of the current study were produced
using 32 week old three parent groups of local Saudi chickens which had been sorted
in a previous experiment into high (H) , low (L) and a random control group (C)
according to their primary antibody response at 7d post im injection with 1ml of 15%
SRBC. Parents were vaccinated late at 31 weeks of age against ND and secondarily
exposed to SRBC antigen at 32 wk of age. Three hatches from each group were
obtained. Half of each hatch was vaccinated at 3 days of age with ND vaccine (HB1)
and SRBC. The other half was left without any vaccination. Antibody titer for all
chicks against ND and SRBC were evaluated at 6, 9, and 12 days of age. Body
weights were recorded weekly and weight gain then calculated. The L group chick
body weight, and weight gain, were significantly (P< 0.05) higher than H group at
all measuring point. The unvaccinated chicks of H group were significantly (P<
0.05) higher than L group for ND titer at all measuring point and for SRBC at the
first two measuring points. The current study demonstrated that the chick antibody
response was influenced by the maternal antibody level for SRBC and ND antigen.
Results of body weight and weight gain emphasized the concept of allocation of
resources between the different needs of one bird. The study spotlighted the
importance of considering maternal antibody level before designing a vaccination
program for early hatched chicks.
Keywords: Newcastle disease, sheep red blood cells, maternal immunity, body
weight
INTRODUCTION
There are many reports in literature over time regarding chick susceptibility to
many pathogens during the first few weeks of age because their immune system is
not fully developed; hence, maternal antibodies are the primary means of antigenspecific protection until adaptive immune responses become fully effective (Hamal
et al., 2006; Davison et al., 2008).The immunoglobulin Y (IgY) is selectively
secreted via the circulation of the hen into egg yolk (Patterson et al., 1962). The
amount of IgY transferred across the follicular epithelium into the yolk is
proportional to the IgY concentration in serum (Al-Natour et al., 2004; Hammal et
al., 2006). The IgY is continuously absorbed by embryo during embryogenesis until
Issued by The Egyptian Society of Animal Production
2
Ahmed
the 2nd day after hatching, providing evidence of passive immunization protection
acquired from hen (Li et al., 1998). The time at which the newly hatched chicks start
to synthesize antibodies endogenously depends on the type of antibody (Hammal et
al., 2006). Lawrence et al. (1981) reported that IgY-secreting B cells are not
detectable in a chick’s plasma until 6 d post hatch. Endogenously synthesized IgM
and IgA antibodies have been detected in plasma of 3 to 4 d old and 12 d old chicks,
respectively (Leslie and Martin, 1973;Martin and Leslie, 1973; Leslie, 1975). The
susceptibility for many poultry diseases was shown to be partly influenced by breed
(Bumstead et al., 1991). Using the dam’s titer to predict the day-old chick’s titer
against certain pathogens would be valuable to poultry clinicians in the field(
Gharaibeh et al., 2008). In chickens, selection for the specific antibody response
against sheep red blood cells (SRBC) has been a frequently used experimental
method for investigating genetic aspects of the immune response as a part of the
adaptive (humoral) immune system (Wijga et al., 2009). Sheep red blood cells
besides their nonpathogenic characteristic were initially chosen for their multiple
antigenic sites, which may stimulate a wide range of immune cells. Because SRBC
are natural products, similarities in certain structural patterns with other natural
products (for instance, similar proteins on the cell membrane), among others
pathogenic organisms, were also expected (Kreukniet, 1995).live lentogenic vaccines
are usually derived from field viruses that have been shown to have low
pathogenicity for poultry but produce an adequate immune response. Hitchner B1
(HB1) and La Sota, became globally the most used veterinary vaccines for Newcastle
disease virus (Alexander et al., 2004). Newcastle disease virus (NDV) antibody titer
were significantly increased by vaccination and by immunization with SRBC, the
SRBC agglutination response was also positively affected by vaccination ( Van der
Zijpp et al., 1981). This study was conducted using parents from two groups
according to their antibody response to SRBC and a control group to investigate the
influence of different levels of maternal antibody to SRBC on immune response to
NDV and SRBC antigens and body weight of young chicks under early vaccination
and non-vaccination program.
MATERIALS AND METHODS
Parent flock and obtained chicks:
The chicks used in the present study were obtained from three groups of local
Saudi parents kindly provided by King Faisal university poultry experimental station.
They were previously evaluated and differed in their primary antibody response to
SRBC antigen as follow, the highest antibody titer group (H) and the lowest antibody
titer group (L) plus a random control group (C). The grouping was based on
individual total antibody titer at 7 days after primary intramuscular immunization
with 1 ml of 15% SRBC using micro heamaglutination (HI) technique (Nelson et. al.
1995). A 32 week old fifty dams and five sires were used in each group to produce
the current experimental chicks. Each parent group was placed randomly within each
group into 5 breeding pens in an open house system with ventilation fans, feeders,
drinkers, wood shave litter and trap nests. Birds were exposed to 17h/d of light
during the experimental period. Feed and water were available ad libitum. Birds were
fed a commercial layer diet with 16% protein and ME of 2700 Kcal/kg feed. The
Egyptian J. Anim. Prod. (2011)
3
regular experimental station vaccination system against NDV was achieved, where
all parents were vaccinated at 31 wk of age with Lasota strain via drinking water
route. At 32 wk of age all birds, secondary intramuscular immunized with 1 ml of
15% SRBC antigen. Average antibody titers of parents as evaluated in a previous
research work at 7 d post secondary exposure were 5.79, 4.36, and 4.08 for H, C, and
L group, respectively. Average antibody titers against ND at 32 weeks of age were
8.36, 7.75, and 6.75 for H, C, and L group, respectively. Starting from wk 32 of age
eggs were collected separately for each group and stored for 10 days at 10°C until
incubation, and then eggs were placed into incubator. Three hatches were obtained
from each group. All chicks were wing banded to identify different groups.
Experimental chicks:
Four hundred fifty one day old chicks were obtained from the three hatches of
each parent group. All chicks were wing banded, weighted to the nearest g and
housed in a five levels cage system for brooding. Feed and water were provided ad
libitum. Cages were placed in an open house system considering the optimum chicks
brooding criteria. Half of the chicks of each hatch for each group were vaccinated
with ND vaccine (HB1 stain) at 3 d of age via eye drop route. Also subcutaneously
injected with 0.5 ml of 15% SRBC suspended in phosphate buffer saline (vaccinated
group). The other half of chicks of each group was left without any vaccination as
(unvaccinated group).
Parameters and data collection:
Body weight was recorded for all chicks at one day old and for two other
consecutive weeks to the nearest gram. The vaccinated chicks of all groups were bled
via the jugular vein at 6, 9, 12 days of age (3, 6, and 9 days post immunization) using
a 0.5-ml insulin syringe with a 28.5-gauge needle. The serum samples were collected
after centrifugation (3000 rpm, 3min) , stored at -20˚C until the assays were run
simultaneously for both SRBC and ND antibody titer. The unvaccinated chicks of all
groups were bled via the jugular vein at 6, 9, and 12 days of age, serum samples were
collected to assess the maternal antibody against SRBC and ND antigens. SRBC
antibodies were assayed using micro heamaglutination technique (Nelson et. al.
1995). ND antibody titer was assayed using microtitre heamaglutination inhibition
(HI) test as described by OIE (2008).
Statistical Analysis
Differences in body weight, and weight gain of all chicks in addition to the
antibody response to SRBC of the unvaccinated chicks were analyzed by a one-way
ANOVA for the group effect. Differences in titers of ND for chicks were analyzed
by a two-way ANOVA for the effect of the group of dam, vaccination status and their
interactions. Data were analyzed using the general linear model procedure of SAS
software (SAS, 2000).
RESULTS
Immune response:
The unvaccinated group of chicks showed antibody response against SRBC and
NDV antigens at 6, 9, and 12 d post hatching (Table 1 and Figure 1). While the
4
Ahmed
vaccinated group showed antibody response against HB1 vaccine but not SRBC
antigen. The unvaccinated chicks hatched from H group recorded higher (P≤ 0.05)
antibody titer than L group at 6 and 9 days of age for SRBC antigen (Table 1) ; and at
6, 9, and 12 days of age for NDV too (Figure 1). No differences were detected in
antibody titer against SRBC or NDV antigen of the unvaccinated chicks hatched
from L and C groups of dams at any of the measuring points (Table 1 and Figure 1).
Table 1. Maternal antibody titer against sheep red blood cells
unvaccinated chicks
Antibody titer to SRBC
Parent group
6d
9d
H1
3.00 ±0.23 A
1.73 ±0.15 A
C
1.64 ±0.18 B
1.36 ±0.18 AB
B
L
1.50 ±0.17
1.09 ±0.18 B
(SRBC) of the
12d
1.21 ±0.09
1.00 ±0.19
1.09 ±0.07
A,B
values within a column with different superscript differ significantly (P ≤ 0.05).
H, C, and L are High, Control, and low group respectively
The titer values are log2 of the reciprocal dilution
1
Vaccinated H
9
Antibody titer (log2)
8
7
Vaccinated C
Vaccinated L
A1
B B
B
6
Unvaccinated H
Unvaccinated C
A
B
B
B
B
B
A
C
B
D
5
Unvaccinated L
C
4
BC BC
BC
3
2
1
0
Day 6
Day 9
Day 12
Figure (1) Antibody titer against Newcastle disease (ND) at 6,9, and 12 days of
age for vaccinated and unvaccinated chicks produced from H, C, and L parent
groups
1
columns within a day with different superscript differ significantly (P ≤ 0.05).
For the vaccinated chicks group the antibody titer against NDV generally had
lower values than unvaccinated group (Figure 1).whereas, the H group unvaccinated
chicks recorded the highest antibody titer within each measuring point over all
groups whether vaccinated or not. Vaccinated chicks hatched from H groups of dams
recorded the highest titer for NDV followed by C, and L groups (P≤ 0.05) at 9 days
of age, while at 12 days of age no differences between the three groups have been
noticed (Figure 1).
Egyptian J. Anim. Prod. (2011)
5
Body weight and weight gain
Chicks hatched from H group dams recorded significant (P≤ 0.05) lower body
weight at 0, 7, and 14 days after hatching than chicks hatched from L group(Table
2). In addition, the weight gain over the first 2 weeks of age of the chicks hatched
from H group recorded significant (P≤ 0.05) lower values than chicks hatched from L
group (Table 2). No significant differences were observed between chicks hatched
from L group and C group in weight gain or body weight at any measuring point
(Table 2).
Table 2. Weight gain and body weight of chicks at 0, 1, and 2 weeks of age
Wight gain
Body weight (g)
(g)
Parent
(0-14 d)
group
One day old
wk12
wk2
1
B
H
23.20±0.26
35.62±0.63B
48.10±1.05B
24.85±0.98B
AB
AB
A
C
23.78±0.27
37.24±0.62
51.72±1.03
27.29±0.96AB
A
A
A
L
24.17±0.24
38.12±0.55
52.57±0.94
28.30±0.88A
A,B
values within a column with different superscript differ significantly (P ≤ 0.05).
H, C, and L are High, Control, and low group respectively
2
weeks 1 and 2 are 7, and 14 days old respectively.
1
DISCUSSION
Grouping of parents according to the primary immune response against SRBC
showed the same trend of response in the early hatched chick response against SRBC
and NDV in this study. The trend of antibody response against NDV, which is
consistent with parent grouping according to the primary immune response to SRBC,
may be explained through the multiple antigenic sites of SRBC which have some
similarities in certain structural patterns with other pathogens (Kreukniet, 1995). The
nature of SRBC may affect the other pathogen (NDV) antibody response and showed
the same trend of response in the maternal antibody. Therefore, using the group of
parents that were selected for high titer to SRBC might be beneficiary to produce
chicks with high antibody response against some poultry diseases.
The unvaccinated chicks hatched from H group showed significant superiority
over the vaccinated group for antibody titer against NDV at 6, 9 and 12 days of age.
In addition, they were significantly superior over C and L unvaccinated chicks at all
measuring points (Figure 1). The antibody titer for the unvaccinated group is high
which may be affected by more than one factor including chicken breed. Transfer of
maternal antibody into the egg yolk is proportional to the IgY concentration in blood
serum (Al Natour et al., 2004; Hammal et al., 2006). The level of maternal antibody
transfer is a major importance when serology for disease diagnosis considered
(Sharma, 2003).The group in this study affect the serum antibody of dams which had
a high level in the H group dam this may explain the higher level of response of the
dams of H group chicks through passive transfer.
The high maternal antibody was accompanied with the low response to
vaccination in the vaccinated group using HB1 vaccine. This vaccine is a live
6
Ahmed
lentogenic vaccine and has low pathogenicity (Alexander et al., 2004(. This vaccine
strain usually is used to vaccinate chicks at early age, including layers vaccinated at
one day of age with this live vaccine (Gilad and David, 1998). This low response
may be explained as, when chicks are vaccinated while having a high levels of
maternal antibody, vaccine may be not highly effective due to vaccine neutralization.
Previous reports explained that when chicks are vaccinated while having a high level
of antibody, failure due to neutralization of the live vaccine is expected (Mondal and
Naqi, 2001; Al Natour et al., 2004). The current research results suggests
reconsidering the vaccination date of the early hatched chicks in Saudi breeds
because it may affect the level of antibody due to the high maternal antibody, which
may have an effect on the vaccine neutralization. The transfer of maternal antibody
against SRBC showed low values in comparison with ND, and declined to be less
than or equal to 1.21 for all dam groups at 12 d of age. This low transfer rate may be
due to the biological nature of the antigen where, a considerable variation for about
17 folds among transfer rate of maternal antibodies against the different pathogens
was observed (Gharaibeh, et al., 2008).
Weight gain and body weight of L group chicks were higher than H group. These
results suggested the inverse relationship between immune response and other traits,
such as body weight and growth, which have been reported previously (Martin et al.,
1990; Parmentier et al., 1996; Mashaly et al., 2000).
In conclusion, the present results suggested that maternal antibody against SRBC
and ND is successfully transferred to the offspring with different levels according to
different maternal antibody level. The results of vaccinated group suggested that the
vaccination program of early hatched chicks should consider the maternal antibody
background to avoid anticipated low response to vaccine. This study also noticed the
negative relationship between body weight of early hatched chicks and their immune
response against SRBC and ND antigens. Further studies for the comparison between
different breeds are needed to determine the effect of genetic background on the
maternal transfer of antibodies for different antigens at different ages.
ACKNOWLEDGMENTS
The author is grateful to Dr. Fahad Al Hur, Department Head for facilitating the
research work. Thanks are also extended to Agriculture Research Station of King
Faisal University for their support in conducting this research. The author also
acknowledges the technical assistance of Abdullah Alnazr, AbdulRazak Al-Abbad
and all poultry research unit staff at the Agriculture Research Station of King Faisal
University.
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‫‪9‬‬
‫)‪Egyptian J. Anim. Prod. (2011‬‬
‫إستجابة اإلجسام المضادة بالكتاكيت حديثة الفقس تحت تاثير التحصين ومستويات مختلفة‬
‫من األجسام المناعية األمية‬
‫أحمد سيد أحمد‬
‫قسم االنتاج الحيوانى والسمكى – كلية العلوم الزراعية واالغذية‪ -‬جامعة الملك فيصل – المملكة العربية‬
‫السعودية‬
‫تم اجراء هذة التجربة لتقييم االتستجببة ببالجسبم المنبعية ضد مرض النيوكبتسل وانتجين كررا الردم الرمرراء‬
‫لالغنرربم فررا ال تبكيررح يدة ررة التقررت ترررح تررب ير كترربءا مختلتررة للمنبعررة االميررة والترصررين المر ررر‪ .‬ال تبكيررح‬
‫المستخدمة ببلدراتسة تم انتبجهب من الث مجموعب من اببء الدجبج المرلا السرووى عمرر ‪ 23‬اتسررو والترا رد‬
‫تررم تصررنيتهب تسررببقب الررا مجموعررة مرتتوررة (هرر ) ومجموعررة منخت ررة ( ل) ومجموعررة كنترررول (ك) مررن ييرر‬
‫االتستجببة بود ‪ 7‬اةبم من الرقن االولا ب ‪ 1‬مرل مرن مرلرول ةرترو علرا ‪ %11‬مرن انتجرين كررا الردم الرمرراء‬
‫لالغنربم‪ .‬االبرربء ترم اتررر ترصرين لهررم علرا عمررر ‪ 21‬اتسررو ضررد مررض النيوكبتسررل وترم تورة ررهم للرقرن ال رربنا‬
‫ببنتجين كرا الدم الرمراء لالغنبم عند عمر ‪ 23‬اتسررو مرب بداةرة جمرب الرريص للرصرول علرا ال تبكيرح‪ .‬رالث‬
‫ىفوررب تترررة تررم جموهرب مررن كررل مجموعررة مررن االبرربء‪ .‬ال تبكيررح التب سررة مررن كررل مجموعررة ب ررل ىفوررة تترررة تررم‬
‫ترصين نصتهب عمر ‪ 2‬اةبم بلقبح ‪ HB1‬ببلتقطير فا الوين مب الرقن ببنتجين كرا الدم الرمراء لالغنبم بينمرب‬
‫ترك النصف االتر من ال تبكيح ب ل ىفوة تترة ىون ا تورةص لالنتجينب ‪ .‬تم تقييم مستو االجسبم المنبعيرة‬
‫ضد مرض النيوكبتسل وضد انتجين كرا الدم الرمراء لالغنبم لجميرب ال تبكيرح علرا عمرر ‪6‬و ‪ 9‬و ‪ 13‬ةروم‪ .‬ترم‬
‫تسجيل الوزن االتسروعا لل تبكيح وتم يسبب مودل الزةبىة الوزنية‪ .‬اظهرر كتبكيرح المجموعرة (ل) وزن جسرم‬
‫وزةبة وزنية اعلا بصورة مونوةة عن المجموعة (ه ) تالل جميب اعمربر القيرب ‪ .‬ال تبكيرح الييرر مرصرنة مرن‬
‫المجموعة (ه ) اظهرر ارتترب مونرو فرا مسرتو االجسربم المنبعيرة ضرد مررض النيوكبتسرل ةتروا المجموعرة‬
‫(ل) تالل جميب اعمبر القيب ببالضبفة الرا نترت االرتترب المونرو فرا مسرتو االجسربم المنبعيرة ضرد انتجرين‬
‫كرررا الرردم الرمررراء لالغنرربم ببلمقبرنررة ببلمجموعررة (ل) عنررد عمررر ‪ 6‬و ‪ 9‬ةرروم‪ .‬اوضرررح الدراتسررة الربليررة ان‬
‫االتستجببة المنبعية ضد مرض النيوكبتسل و انتجين كرا الدم الرمراء لالغنبم تب ر بمستو االجسبم المنبعيرة‬
‫االمية‪ .‬اكد نتربج وزن الجسرم وموردل الزةربىة الوزنيرة بتلر التجربرة علرا متهروم تروازن االيتيبجرب المختلترة‬
‫للطبجر الوايد‪.‬كذل القح تل الدراتسة ال وء علرا اهميرة االترذ فرا االعترربر مسرتو االجسربم المنبعيرة المنقولرة‬
‫من االم رل تصميم برام الترصين لل تبكيح يدة ة التقت‪.‬‬