Seroprevalence of Infectious Bursal Disease in Flocks of Indigenous Nigerian Ducks (Anas platyrhynchos)

A serological survey was conducted to determine the prevalence of Infectious Bursal Disease (IBD), using the quantitative Agar Gel Precipitin Test (AGPT), in flocks of apparently healthy, unvaccinated adult indigenous Nigerian ducks in Oyo and Osun states of Nigeria. Of the 126 sera tested, 24 (19.1%) were positive for IBDV precipitins. None of the 15 samples from Farm A was positive but 9 (30.0%) from Farm B and 15 (18.5%) from backyard flocks were positive for IBDV antibodies. 15 of the positive samples had a titre of 1:16, 6 had titre of 1:32 while 3 had titre of 1:64. The Geometric Mean Titre (GMT) for the Farm B and indigenous duck samples were 21 and 23, respectively. This range of antibody titres detected in unvaccinated ducks is an indication of previous exposure to IBDV and is sufficiently high to suggest that indigenous Nigerian ducks have an important role in the natural history of IBD and could serve as carriers of the virus, thereby complicating IBD control measures.