Adult houbara bustards (Chlamydotis undulata) and juvenile kori bustards (Ardeotis kori) were given four regimens of commercially available inactivated and live poultry paramyxovirus type 1 (PMV-1) vaccines. Immunologic response to vaccination was assessed by hemagglutination inhibition assay of serum. Kori bustards, to which a dose of 0.5 ml of a commercially available inactivated vaccine for poultry had been administered intramuscularly (0.15 ml/kg body weight), failed to develop hemagglutinating antibodies, but antibody titers of low intensity and duration were detected following administration of a second and third subcutaneous dose of 2.0 ml vaccine per bird (0.40-0.45 ml/kg). In subsequent trials, when inactivated vaccine was administered subcutaneously at 1.0 ml/kg body weight following two or four live vaccinations administered by the ocular route, juvenile kori bustards developed higher, more persistent titers of antibodies. Kori bustards given four live vaccinations followed by inactivated vaccine developed higher titers of longer 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 vaccine, that were given a booster dose of inactivated vaccine maintained high mean antibody titers (or = log, 5) for 52 wk. The authors recommend that inactivated PMV-1 vaccine should be administered by subcutaneous injection of 1.0 ml/kg vaccine to bustards. Adult bustards, previously vaccinated with inactivated vaccine, should be vaccinated annually with inactivated vaccine. Juvenile bustards should receive a second dose of inactivated vaccine 4-6 mo after the first dose of inactivated vaccine. Even though inactivated PMV-1 vaccines induced hemagglutination inhibition antibodies and produced no adverse reactions, further studies will be required to determine the protective efficacy of the antibody.
