Serological and growth rate responses to the use of chicken Newcastle disease vaccines in pigeons

ObjectiveIn the face of an outbreak of pigeon paramyxovirus (PPMV), a vaccination response study was undertaken to determine if pigeons in Australia would produce a serological response similar to that considered protective in chickens. DesignA vaccination study evaluated serological response and safety criteria in groups of 20 pigeons. MethodsOne group served as unvaccinated controls; one group was vaccinated with a live V4 strain of Newcastle disease virus (NDV) and subsequently revaccinated 28 days later with an inactivated La Sota strain vaccine; the third group was vaccinated twice with the inactivated La Sota strain vaccine 28 days apart. Serum was collected from the birds for serology 28, 56, 120 and 196 days after each treatment. Safety of the vaccines was determined using observation of the birds and body weight change. Serology was performed using three variations of the haemagglutination inhibition (HI) test, including chicken red blood cells (RBC) with either V4 NDV or PPMV as the antigen and pigeon RBC with V4 NDV as the antigen. A commercial NDV ELISA test was also used. ResultsAt 28 days after the second vaccination, the geometric mean titres were 6.8 and 7.3 for the live/inactivated vaccine regimen and the inactivated/inactivated regimen, respectively. The serological response of birds vaccinated with the inactivated/inactivated regimen was significantly greater than that of the controls for all of the serological tests used. ConclusionVaccination of pigeons with two doses of chicken NDV vaccine 28 days apart was safe and resulted in antibody levels considered protective for NDV in chickens.