| dc.description.abstract | Two consecutive experiments were conducted to evaluate the influence of dietary composition, specifically protein and amino acid profile, on performance parameters, oocyst output, and lesion development in male and female replacement broiler breeders of two different genetic lines vaccinated with a live coccidiosis vaccine. Dietary formulations were based on either breeder specific recommendations or formulations of a broiler integrator. On day 28, males of each genetic line were added to female pens to evaluate the effect of co-mingling on male performance. Lesion assessment was performed on three separate occasions per each experiment. Fecal material was collected to determine oocyst cycling patterns.
During experiment 1, flock uniformity was improved (P less than/equal to 0.05) in Line A males fed the integrator diet. Increased body weight and improved uniformity of Line B females was observed with the breeder recommended diet. Co-mingling negatively impacted (P less than/equal to 0.05) male body weight. Multiple oocyst peaks were observed in both genetic lines, with the first peak occurring at approximately 16 to 18 days post placement. This first peak tended to have the highest observed magnitude and corresponded with the highest level of intestinal lesions observed during the experiment.
In experiment 2, diet impacted (P less than/equal to 0.05) average body weight in Line A males, Line B males, and Line B females. Line A males fed the breeder recommended diet had increased (P less than/equal to 0.05) body weight at the termination of the experiment. Line B males and females fed the breeder recommended diet had increased (P less than/equal to 0.05) body weights throughout the experiment beginning on day 7. Negative effects (P less than/equal to 0.05) on male body weight resulting from co-mingling were observed. Oocyst peaks were delayed and at a lower magnitude in both genetic lines compared to peaks observed in experiment 1. Dietary interactions were observed in both experiments where magnitude of peak, duration of oocyst output, and severity of lesion development was influenced by diet in both male and female genetic lines. These data indicate that co-mingling negatively impacts male performance and dietary composition can impact male and female performance, oocyst cycling, and lesion development during coccidiosis vaccination in replacement broiler breeders and should be taken into consideration when rearing replacement broiler breeders. | en |
