This research program included a series of experiments to investigate the effect
of starter diet protein level on the performance of broilers vaccinated with Coccivac®-B
and subsequently challenged with a mixed species Eimeria challenge compared to nonvaccinated
broilers. Pre-challenge performance data indicates that vaccination may
decrease body weights and increase feed conversion ratio (FCR) with vaccination. The
time period associated with the observed effects is between 13 to 17 d of age. This
reduction in performance of vaccinated broilers versus non-vaccinated broilers was
eliminated by the conclusion of the experiments (27 d) in the higher protein diets.
Vaccination was effective at generating protective immunity against the Eimeria
challenge evidenced by significantly increased body weight gains, improved feed
conversions, reduced post-challenge mortality, and reduced lesion development in
vaccinated broilers compared to non-vaccinated.
The final experiment included the comparison of Coccivac®-B to Bio-Cox®
(salinomycin) for controlling field strain Eimeria in broilers reared on two different dietary rations varying in protein concentration. Diet A had a lower protein
concentration than Diet B. On day 14, Eimeria collected from commercial broiler farms
in Texas were spray applied to the litter in all pens. Broilers reared on Diet B were
heavier at Day 40 while body weights at day 50 were similar for all groups. Broilers fed
Diet B had lower FCR during the starter and finisher diets. Broilers fed salinomycin had
lower FCR for the starter and grower diets while vaccinated broilers had lower FCR
during the withdrawal period. Cumulative FCR for the entire grow out period were
similar for all groups.
These data indicate that vaccination can be utilized as an anticoccidial preventive
and are suggestive that reduced protein concentration of starter diets can lead to
significant losses in broiler performance when utilizing a vaccination program to prevent
coccidiosis. Feeding an appropriately formulated diet while vaccinating broilers with
Coccivac®-B as an alternative to the use of salinomycin yields at least equivalent if not
elevated performance in the presence of field-strain Eimeria during grow-out with no
effect on the cost of production.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/4713 |
| Date | 25 April 2007 |
| Creators | Lee, Jason Thomas |
| Contributors | Caldwell, David J. |
| Publisher | Texas A&M University |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Dissertation, text |
| Format | 361490 bytes, electronic, application/pdf, born digital |
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