Prevalence of Infectious Bursal Disease in Commercial Layer Chickens in Niger State

This study determines the prevalence of infectious bursal disease (IBD), also known as Gumboro disease, in commercial layer flocks in Niger State, located in Nigeria's North Central geopolitical zone. IBD, caused by the infectious bursal disease virus (IBDV), causes immunosuppression and mortality in young chickens and remains a significant constraint on poultry production profitability in Nigeria. Using a cross-sectional design, 25 commercial layer farms in three agricultural zones of Niger State were surveyed. Serum samples were collected from 300 chickens aged six to sixteen weeks and tested for IBDV antibodies using ELISA. Bursa of Fabricius from 80 birds that had died on the farms during the study period were examined histopathologically for characteristic IBD lesions. Farm management data including vaccination schedules, biosecurity practices, and flock history were obtained by structured interviews with farm managers. Findings revealed an overall IBDV antibody prevalence of 76 percent across surveyed farms. Histopathological evidence of bursal lymphoid depletion consistent with IBD was detected in 58 percent of examined bursae. Farms with inadequate vaccination programmes and those receiving chicks from multiple hatcheries showed significantly higher IBD seroprevalence. The study recommends the review of vaccination protocols, sourcing of chicks from single certified hatcheries, and the adoption of more virulent vaccine strains appropriate for high-challenge environments in Niger State. Keywords: infectious bursal disease, layer chickens, Niger State, vaccination, seroprevalence.