Experimentally induced infections bovine keratoconjunctivitis: effectiveness of a pilus vaccine against exposure to homologous strains of Moraxella bovis.
A study was conducted to determine whether vaccination with sonicated pili of Moraxella bovis would protect cattle from subsequent infection and disease when experimentally challenged by exposure to homologous cultures of M bovis. Some calves were intramuscularly inoculated 2 times with pili of M bovis suspended in water, and others were subcutaneously inoculated 2 times with pili of M bovis suspended in oil; 21 days were allowed between inculations. Controls were nonvaccinated calves. Fourteen days after the last inculation, all calves were exposed to virulent homologous cultures of M bovis. The results indicated that vaccination with sonicated pili of M bovis may induce protective immunity against homologous strain challenge exposure. Vaccines in oil that were injected subcutaneously protected to a greater extent than did vaccines in water that were injected intramuscularly. The development of inflammatory nodules at the site of inoculation was associated with resistance to infection and disease. Only 1 of the vaccinated calves that resisted disease lacked precipitating antibodies against sonicated pili at the time of the challenge exposure. This calf had antibodies 2 weeks later.
D000818:Animals; D000907:Antibodies, Bacterial / Q000032:analysis; D001424:Bacterial Infections / Q000276:immunology* / Q000517:prevention & control / Q000662:veterinary*; D001428:Bacterial Vaccines; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology / Q000517:prevention & control*; D007637:Keratoconjunctivitis / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D009016:Moraxella / Q000254:growth & development / Q000276:immunology*
D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines