Antibody response of kori bustards (Aredeotis kori) and houbara bustards (Chlamydotis undulata) to live and inactivated Newcastle disease vaccines

Adult houbara bustards (Chlamydotis undulata) and juvenile kori bustards (A rdeotis kori) were given four regimens of commercially available inactivate d and live poultry paramyxovirus type 1 (PMV-1) vaccines. Immunologic respo nse to vaccination was assessed by hemagglutination inhibition assay of ser um. Kori bustard, to which a dose of 0.5 ml of a commercially available ina ctivated vaccine for poultry had been administered intramuscularly (0.15 ml /kg body weight), failed to develop hemagglutinating antibodies, but antibo dy titers of low intensity and duration were-detected following administrat ion of a second and third subcutaneous dose of 2.0 mi vaccine per bird (0.4 0-0.45 ml/kg). In subsequent trials, when inactivated vaccine was administe red subcutaneously at 1.0 ml/kg body weight following two or four live vacc inations administered by the ocular route, juvenile kori bustards developed higher, more persistent titers of antibodies. Kori bustards given four liv e vaccinations followed by inactivated vaccine developed higher titers of l onger duration compared with kori bustards given two live vaccines followed by inactivated vaccine. Antibody titers of kori bustards given inactivated vaccine were higher and more persistent than the antibody response to live vaccination. Houbara bustards, previously vaccinated with inactivated vacc ine, that were given a booster dose of inactivated vaccine maintained high mean antibody titers (greater than or equal to log(2) 5) for 52 wk. The aut hors recommend that inactivated PMV-1 vaccine should be administered by sub cutaneous injection of 1.0 ml/kg vaccine to bustards. Adult bustards, previ ously vaccinated with inactivated vaccine, should be vaccinated annually wi th inactivated vaccine. Juvenile bustards should receive a second dose of i nactivated vaccine 4-6 mo after the first dose of inactivated vaccine. Even though inactivated PMV-1 vaccines induced hemagglutination inhibition anti bodies and produced no adverse reactions, further studies will be required to determine the protective efficacy of the antibody.