Seroprevalence of infectious bursal disease in non-vaccinated indigenous and exotic chickens on selected farms around Gaborone, Botswana.

Sera from nine out of 30 (30.0%) apparently healthy unvaccinated indigenous (Tswana) chickens had precipitating antibodies to infectious bursal disease (IBD) virus using the agar gel precipitation test. Similarly, sera from 11 out of 49 (22.4%) chickens of exotic breeds with no history of vaccination against IBD were positive for antibodies against the virus.