Outbreak of infectious bursal disease in a flock of 14 weeks old ISA brown pullets, Sokoto State, Nigeria

This study reported the clinical signs and pathological effects of Infectious bursal disease (IBD) virus in 14 week old Isa brown IBD- vaccinated pullets. Clinical signs, pathologic lesions, morbidity as well as mortality rates on the natural outbreak of infectious bursal disease (IBD) in pullets under deep litter system in a commercial poultry farm in Sokoto, Nigeria were observed and recorded. Tissues of bursa of Fabricius (BF) were collected and fixed in 10% buffered formalin and processed for histopathological examinations. During the outbreak, morbidity and mortality rate of 40% and 22% respectively were recorded and the disease course lasted for 7 days. The disease was diagnosed based on clinical signs, gross- and histo- pathologic lesions as well as agar gel immunodiffusion test (AGID). Clinical signs, gross lesions, and histopathological findings were characteristic of very virulent infectious bursal disease.