EFFECTS OF DIFFERENT TIMING OF ROUTINE VACCINATION SCHEDULES ON GROWTH PERFORMANCE MORTALITY RATE AND BLOOD PARAMETERS OF BROILERS
This study was conducted to find the effect of the delayed routine vaccination schedules on growth performance, blood parameters and immunity levels of broilers reared in a humid tropical part of Nigeria. A total of 90 broiler chickens were procured and sorted into three treatments (control, 1 week delay in vaccination and 2 weeks delay in vaccination). The results showed significant differences (P < 0.05) in all growth parameters studied with lower values for broilers with delayed vaccination schedules (Treatment 2 and 3). Shank length and gains in shank length were not significantly (P>0.05) affected by delayed vaccination schedule. The blood parameters (PCV and WBC) values were significantly (P<0.01) lower in birds whose vaccination schedule was delayed for two weeks, (Treatment 3) compared to other treatments while immunity levels were significantly (P<0.01) lower in Treatment 3 compared to Treatments 2 and 1 respectively. It was concluded that delayed vaccination schedule of up to two weeks considerably affected growth performance and immunity status of broilers.