Performance influenced by diet in coccidiosis-vaccinated broiler breeders
Integrators rearing replacement broiler
breeders should take into account the
finding that early flock performance can
be influenced by dietary composition,
depending on the genetic line and gender,
Leslee A. Oden, of Texas A&M University,
said at the American Association of Avian
Pathologists annual meeting held last July.
Oden and associates conducted a study to
determine the effect of diet on oocyst output,
gross lesion development and performance
in replacement broiler breeders from two
genetic lines that received Coccivac-D,
a live-oocyst coccidiosis vaccine, at 1
day of age.
There were two lines of breeders in the
study — Line A and Line B — and in each
group there were 240 males and 576 females.
After delivery from the hatchery, birds
received either the integrator diet or a diet
recommended by the primary breeder of
each line, Oden said. The protein concentration
was higher in the breeder-recommended
diets than in the integrator diets.
Oocyst shedding was evaluated and gross
lesion scores were determined, as well as
average bodyweight and flock uniformity,
she said.
In Line A, oocyst peaks varied with gender
and the dietary program. Breeders fed the integrator diet had significantly higher lesion scores in the upper region of the small intestine when compared to breeders fed the breeder-recommended diet. There were no differences in bodyweight during the course of the trial, but on days 28 and 42, males fed the integrator diet had improved uniformity, she said.
In Line B, breeders fed both diets had oocyst
peaks between days 14 and 18; the peaks
varied with gender and the dietary program.
Males on the integrator diet had an
increased lesion score in the mid-intestine
compared to birds on the breederrecommended
diet. Females fed the
breeder-recommended diet had increased
bodyweight from days 21 to 42 and improved
uniformity on days 28 and 42 compared to
birds on the integrator diet, Oden said.
Lesion development and oocyst output are
related and tend to be at their highest levels
around day 17 when rearing replacement
broiler breeders on fresh pine shavings,
Oden concluded. The magnitude of oocyst
output and number of identifiable peaks are
influenced by genetic line, gender and
dietary composition.
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