Epidemiological investigation of infectious Bursal disease in Bangladesh

An epidemiological investigation of infectious bursal disease (IBD) was conducted from January 2000 to December 2001. A total of 1056 farms were surveyed for epidemiological investigation. Clinical diseases mostly occur between 3 and 6 weeks of age. Highest morbidity and mortality were observed in cockerel (49.4% and 25.5%) followed by layer (33.4% and 17.2%) and broiler (33.0% and 16.3%) chickens. Highest morbidity (36.3%) and mortality (19.7%) were observed between 21 to 30 days. The mortality observed in vaccinated and non-vaccinated commercial breeds was 17% and 82%, respectively. Similar morbidity and mortality were found in heavy and light birds. It was observed that continuous antibiotic supplementation and stress factors reduced antibody production.