Abstract
A study was conducted on the impact of aflatoxin in the feed on immunization against infectious bursal disease (IBD) in chickens using an attenuated live vaccine. Three-hundred-and-ninety broiler chicks were used. The aflatoxin feeding of 100 and 200 parts/10(9) of AFBI started when chicks were 10 days old and continued for 8 weeks. An attenuated live IBD virus vaccine was administered in drinking water at 2 and 5 weeks of age. A field IBD virus strain was used for challenge. The antibody titres, bursal indices, bursal lymphocyte counts and feed conversion ratios were monitored. The impact of aflatoxin on reduced body weights and lower antibody titres was shown to be highly significant (P<0.0001).