Submitted to: Avian Diseases
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/16/2006
Publication Date: 9/1/2006
Citation: Kapczynski, D.R., Wise, M., King, D.J. 2006. Susceptibility and protection of naive and vaccinated racing pigeons (Columba liva) against exotic Newcastle disease virus from the California 2002-03 outbreak. Avian Diseases. 50(3):336-341. Interpretive Summary: Newcastle disease is considered to be one of the most important viral diseases of poultry worldwide. The role of free-flying birds to spread the virus to commercial poultry has been established. The objectives of the present study were to extend the knowledge of susceptibility and protection of racing pigeons against U.S. exotic Newcastle disease (END) virus. The results indicate that pigeons are less susceptible to END than chickens and display few clinical signs of disease following exposure to the virus. Although vaccination decreases the amount of virus shed, the birds will continue to shed the virus up to 2 weeks after infection.
Technical Abstract: The susceptibility, immune response and protection to challenge following vaccination in racing pigeons was assessed using the 2002-03 exotic Newcastle disease (END) virus responsible for the most recent major outbreak in southern California. Immunologically naïve pigeons appeared resistant to disease, regardless of dose, following a natural route of exposure. Twenty percent morbidity was observed in each group of birds receiving between 102.1-108.1 EID50/bird, with one bird succumbing to challenge in the 108.1EID50/bird group at day 12 post-inoculation . Although resistant to disease, birds in all groups continued to shed virus from either oral or cloacal route at the end of the 14-day sampling period, and seroconversion was only observed in birds receiving > 106.1EID50. Single or double vaccination of juvenile and adult birds with pigeon paramyxovirus virus-type 1 (PPMV-1) vaccine followed by END challenge with 106.1 EID50/bird decreased the duration, incidence and viral load. A positive correlation was observed between the presence of hemagglutination-inhibiting antibody titers at challenge and decreased viral. Overt clinical signs of disease were not observed in any PPMV-1 vaccinated birds following challenge.