Detection of haemagglutination inhibition antibodies against Newcastle disease virus in unvaccinated indigenous chickens in Maiduguri, Borno State, Nigeria.

An examination of 200 serum samples from unvaccinated indigenous (local) chickens in Maiduguri, Borno State (Nigeria) using the haemagglutination inhibition (HI) test showed 73 sera to be positive and 127 to be negative for antibodies against Newcastle disease virus. The highest antibody titre observed was 1:128. The prevalence rate was higher (46.9%) in adult chickens than in young chickens of less than 12 weeks (23%). Presence of HI antibodies in unvaccinated indigenous chickens indicates that these birds had contracted infection and recovered thereafter.