Technically Speaking
Dr. Phillip Hargis on formulating feeds for birds that have been vaccinated for coccidiosis
Phillip Hargis, Ph.D.
Nutritionist
Hargis & Associates
Batesville, Arkansas
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Introduction
The goals of every poultry feed program
are to provide the cheapest feed
cost per pound of meat produced,
improve corporate profits, and foster
acceptable feed mill production and
bird processing.
However, the introduction of coccidial
vaccines, such as Coccivac-B, has
created additional dietary goals necessary
to support the new style of coccidiosis
control and the trend toward
larger bird size. These goals are to support
gut integrity, control broiler
growth and maintain the success of the
overall anticoccidial program.
Five Key Points
For a successful Coccivac-B program,
there are at least five points of nutritional
consideration required. These do
not constitute a complete list of considerations;
these are not necessarily the
top five, nor are they in any order of
importance; they simply provide some
sense of the nutritional effort needed
for a successful broiler production cycle
using Coccivac-B.
1. Total vitamin/trace mineral supplementation.
Vitamin and trace mineral
supplementation is a must since
vitamin absorption is reduced due to
gastrointestinal tract irritation. Vitamin
D3-related chronic skeletal problems
are an example of reduced nutrient
intake.
Trace mineral intake is challenged
due to gut irritation, so stress-related
minerals are needed. Zinc must be
increased. Organic selenium is a plus.
A critical review of premix specifications
is required. Premixes must be tailored
for the coccidiosis control program
and take into account feed performance
capabilities, the mixing situation
at the feed mill, broiler housing
conditions and genetics. One example
of a premix modification might be a 2X
to 3X increase in Vitamin E.
2. Diet quality. The goal is to reduce
gut irritation that may occur after coccidial
vaccination. For birds to develop
immunity to coccidia organisms after
vaccination, the live oocysts they
receive from the vaccine must invade
the intestinal tract and reproduce. In
the process, the gut may become
stressed, increasing the risk for development
of necrotic enteritis. The diet,
however, can be designed to provide
nutrients that enable the epithelial tissue
to recover, minimizing the impact
of enteritis.
A good-quality diet would include
highly digestible animal proteins.
Elevated initial peroxide value ingredients
should be controlled and microbial-
containing ingredients monitored.
Abrasive or less digestible ingredients
in the diet should be replaced with
highly digestible ones.
For example, it is helpful to include
fish meal and fish oil into analog proteins.
A diet with corn rather than
wheat may reduce the incidence of
enteritis. Poultry fat may be preferable
to blended fat in the diet.
Beware, however, that summer corn
may be subject to mold and other damage
and be of poor quality, whereas
new fall and winter corn crops generally
are of higher quality.
3. Pulling feed during heat. Pulling
feed during heat reduces the intake of
companion drugs so that the drug
intake per bird per day is below effective
levels. For the drugs to be effective,
their dietary level must match daily feed
intake. This can be accomplished by
feeding 20 grams virginiamycin/ton of
feed, for example, versus 10 to 15
grams/ton.
Birds coming out of the off-feed
period tend to gorge on feed, which
stresses the gastrointestinal system.
Coupled with the reduced intake of
companion drugs, the risk for enteritis
is increased. Feed restriction programs
on broilers in a coccidial vaccine program
should be severely reduced if not
eliminated.
4. Dietary profile of feeds must fit
the situation. The broiler feed program
for birds vaccinated with
Coccivac-B must be tailored to meet the
needs of the birds according to age and
growth stage.
Between one and 16 to 21 days,
birds should be provided a slow to
moderate start with starter feed
designed to help heal the gut and maintain
gut health. Dietary changes should
be avoided at ages 18 to 20 days of age.
The dietary nutrient profile up to 21
days of age should support structural
development.
From days 16 to 33 days of age,
healing the gut and maintaining gut
health remains an important goal in
order to avoid enteritis problems. The
dietary nutrient profile of this grower
feed should support drastic bird growth
over a short time. In other words, it's
time to fill up the gas tank with high
test fuel.
From 33 to 60 days of age, the goal
is fast growth with withdrawal feed.
There is no time for healing, so the
healing process should be complete by
this time.
5. Right companion drug for the
situation. Companion drugs administered
with Coccivac-B include virginiamycin,
tylosin, bacitracin MD, zinc bacitracin,
lincomycin and bambermycins.
Companion drugs can be either growth
promoters, bacterial control agents or
both. It is important to match the drug
capability with the time of year, with
gastrointestinal tract challenges and the
general bird health in the field at the
time of Coccivac-B use.
Feed Mill Impact
Coccivac in broilers can produce the
same feed cost per pound of meat that
can be attained with an anticoccidial
drug program. This can be accomplished
by designing a feed program
that promotes healing and nutrient
absorption, thus supporting broilers
during the challenge periods presented
by use of the vaccine. In other words,
an investment in the Coccivac feeding
program enables birds to overcome
intestinal challenges and perform up to
expectations.
The Coccivac feeding program can
be much simpler than a traditional
feeding program utilizing in-feed coccidiostats.
Milling costs can be reduced,
there are fewer variations per ton of finished
feed and feed delivery is less
complicated. The result is a slightly
cheaper feed cost per pound of meat
produced.
Milling is reduced by decreasing the
number of drugs in the microsystem,
which streamlines the mixing
process. The Coccivac
feeding program allows you
to feed the finisher/withdrawal
feed for longer periods
of time. This allows the
feed mill to run its finisher/
withdrawal production
cycle for several shifts
before changing the batch
run. Milling costs are slightly
reduced. Longer withdrawal feeding
periods also can reduce the cost of
hauling feed, increasing tons hauled
per manhour worked.
Conclusion
Coccivac-B can be successfully used in all larger bird situations if the feeds support the birds during the gastrointestinal tract challenges brought to the program by Coccivac-B. There may be some scares due to weight gain delay during the growing period, but the final results will compete with any drug program.