Evaluation of humoral immune response, body weight and blood constituents of broilers supplemented with phytase on infectious bursal disease vaccination

Abstract

Phytase inclusion in phosphorus (P) deficient diet increases the bioavailability of nutrients and plays, indirectly, a role in biological function of many metabolic processes. The possibility of using phytase in diet might influence immune, growth and blood performances of animals. The objective of the study was to assess the effect of local bacterial phytase on humoral immunity in association with weight and blood characteristics of infectious bursal disease (IBD) vaccinated broilers. Male-day-old Cobb-broilers were assigned into four groups based on phytase treatments (0, 500, 1,000 and 1,500 fitase units per kg of diet) with 12 cages comprising three replicates per treatment, each treatment containing 15 birds. They were vaccinated with an IBD vaccine (IBD UPM93) and were fed formulating P (0.19%) deficient diet from 1 to 42 day of age. Results indicated that although serum IBD antibody, IgM, and IgG were not increased, mucosal IgA contents were increased with increasing phytase doses. Data on bird's growth performance revealed that cumulative live weights were increased significantly (p < 0.05) to graded levels of phytase and the highest enzyme level commenced best performance. Results suggest that the local phytase supplementation in low phosphorus diet will improve mucosal IgA contents and body weights of birds.