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ALTERNATE DAY FEEDING: AN EFFECTIVE STRATEGY FOR PRODUCING
BROOK TROUT STOCKERS
Stephen G. Stowell, John R. Foster & Brent C. Lehman
Fisheries, Wildlife & Environmental Science Department
State University of New York, Cobleskill, NY 12043
In many state hatcheries, trout reared for sport
fisheries typically take 16 months to reach a
stocking size of 8.5 -12 inches (216-305 mm).
These hatcheries focus
on meeting a minimum
stocking size, not on
maximizing growth.
Maintenance requirements of the alternate day fed
tank were significantly lower than the daily fed tank.
Growth rate of fish fed daily was .66 mm day.
Alternate day fed fish grew at .44 mm day.
Water Quality was significantly better among alternate
day feeding, with higher oxygen and lower ammonia.
Further, state hatcheries
are often asked to
maintain production on
decreased budgets.
This study examined the feasibility of producing
stocker size brook trout, Salvelinus fontinalis, utilizing
an alternate day feeding strategy to reduce labor
& feed costs and improve water quality.
Feed Assimilation was initially lower for
alternate day feeding, but after the first few
months it did not differ from the daily feeding.
Feed Assimilation Rate
100
Alternate Day
90
% Feed Assimilation
This study was conducted at the State University
of New York at Cobleskill’s cold-water hatchery.
Alternate day feeding could be a cost effective
strategy for producing brook trout stockers.
Daily
Over a 16 month grow-out period, alternate day
fed fish would reach the target stocking range of
8.5-12 in.
80
70
60
50
Similar to Ali et al. (2010), alternate day feeding
resulted in lower feed costs, better water quality,
and less labor costs for feeding and cleaning.
40
30
20
10
0
Winter
Two, 500-gallon circular tanks were stocked with
200 brook trout (171 mm mean length) and fed
Zeigler Gold 3/16th floating trout diet.
One tank was fed daily
(morning-afternoon), and
the other tank was fed
twice every other day.
Lengths and weights of 30
randomly selected fish
from each tank were used
to
calculate
condition,
growth
and
feed
assimilation,
Temperature and dissolved
oxygen were measured
each
day,
nitrite
&
ammonia were measured
weekly.
Spring
Summer
Fall
Feed assimilation of alternate day feeding
improved throughout the study suggesting that
more efficient food utilization was occurring with
alternate day fed fish (Bolivar et al., 2006).
Condition in the first month of the experiment
was lower for alternate day fed fish.
Condition of alternate day fed fish did not differ
significantly from daily fed fish.
SUNY Cobleskill Fisheries & Aquaculture students helped
conducted this study.
NYSDEC Hatchery Manager Scott Wanner (Rome) and
NYSDEC Fish Culturist Anthony Bruno (Chateaugay)
provided valuable advice and information.
Bolivar, B., Boy, E., Jimenez, T., Brown, C.L. 2006. Alternate-Day
Feeding Strategy for Nile Tilapia Grow Out in the Philippines: Marginal
Cost-Revenue Analyses. N. Am. J. of Aquaculture. Vol. 68, (2).
Ali, M., Hayward, R.S., Bajer, P.G., Whitledge, G.W. 2010.
Maintenance-Submaximum Feeding Schedules for Reducing Solid
Wastes and Improving Feed Conversion in Aquaculture. Journal of the
World Aquaculture Society. I3) 319-331.