Abstract
Yellow-feathered broiler chickens generally have a longer growth cycle than white broilers and therefore face different coccidiosis challenges. General single vaccine and drug regimens struggle to prevent coccidiosis for yellow broilers. In this study, a single vaccine, and a combination of coccidiostat regimens was employed to explore the preventative and control effects of different pilot regimens on coccidiosis in yellow-feathered broilers. A total of 2,000 one day old Chinese Huang Youma female broilers were allocated into 4 experimental groups, each with 5 replicates. All birds were fed the same starter feed from Days 1 to 25, and all groups were inoculated with a vaccine on Day 4. After Day 26, the groups were then fed as follows: (1) Negative control group: basal diet + vaccine (NC); (2) NC + maduramycin (NCMD); (3) NC + narasin (NCNR); and (4) NC + salinomycin (NCSL). From Days 26 to 75, the NCNR group had a lower FCR than the other groups. The 75-d BW was higher in the NCNR group than in the NCSL group but was not significantly higher than that in the NC and NCMD groups. The growth performance followed the same trend during the whole experiment (Days 1-75). Compared to the NC group, the NCNR and NCSL groups had higher intestinal mucosa SIgA concentrations at Day 40 and Day 60 (P < 0.001); however the NCMD group had lower IgG levels at Day 40 and Day 60 (P = 0.036, P = 0.006 respectively). The combination groups had significantly reduced AKP levels and urine acid concentrations at Day 60 in comparison to those of the NC group (P = 0.004). The NCNR and NCMD groups had less severe intestinal coccidiosis lesion scores than the NC and NCSL groups in older birds. Thus, a single vaccine and/or combinations with different coccidiostats had different effects on broilers. The NCNR group showed comparatively better growth performance, blood biochemical indices, immune response, and coccidiosis lesion scores.