Influence of diet on oocyst output and intestinal lesion development in replacement broiler breeders following live oocyst coccidiosis vaccination

• Published in: Journal of applied poultry research Vol. 21; no. 3; pp. 445 - 459
• Main Authors: Oden, L. A., Lee, J. T., Pohl, S. K., Klein, A. E., Anderson, S. A., Dougherty, S. D., Broussard, C. T., Fitz-Coy, S. H., Newman, L. J., Caldwell, D. J.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Oxford University Press 01-09-2012
• Subjects: oocyst shedding; live oocyst vaccination; lesion development; broiler breeder; protein
• ISSN: 1056-6171; 1537-0437
• DOI: 10.3382/japr.2010-00264

SUMMARY
Two consecutive experiments were conducted to evaluate the influence of diet on oocyst shedding and lesion development in replacement broiler breeders of 2 different genetic lines after coccidiosis vaccination. The first experiment was conducted on fresh pine shavings as the litter source, whereas the second trial was conducted on the used litter from the first experiment. Dietary formulation was based on either breeder-specific recommendations or formulations of a broiler integrator. Fecal samples were collected every other day beginning on d 6 and continuing throughout the experiment to determine oocyst shedding. Lesion assessment was performed at selected time points in both experiments to evaluate gross and microscopic intestinal lesions. In experiment 1, multiple peaks in oocyst output were observed in both genetic lines, with the first peak occurring at approximately 16 to 18 d after placement. This peak tended to have the highest observed magnitude and corresponded with the highest level of intestinal lesions observed during experiment 1. Oocyst cycling in experiment 2 followed a somewhat different pattern. Peaks were delayed and at a lower magnitude. Dietary interactions were observed in both experiments, with amount and duration of oocyst shedding and severity of lesion development being influenced by diet in both male and female genetic lines. Increased lesion severity was observed in both genetic lines fed the integrator diet as compared with the breeder-recommended diet; however, the relationship of shedding and diet was dependent on genetic line and sex. Therefore, nutrient density affects oocyst cycling and lesion development during coccidiosis vaccination in replacement broiler breeders.