THE EFFECT OF DOSE, ROUTE AND VIRULENCE OF BOVINE HERPESVIRUS-1 VACCINE ON EXPERIMENTAL RESPIRATORY-DISEASE IN CATTLE

  • 1 January 1983
    • journal article
    • research article
    • Vol. 47  (2) , 133-139
Abstract
Three experiments were conducted with calves in which, following i.m. or intranasal vaccination with virulent or attenuated bovine herpesvirus 1, calves were protected against bovine herpesvirus 1.sbd.Pasteurella haemolytica challenge. Calves receiving low doses of vaccine had lower levels of antibody and greater evidence of virus replication upon challenge than those receiving higher doses. In contrast, 11/13 unvaccinated controls had fibrino-purulent pneumonia following challenge. The immune response developed later in younger calves and those given low doses of vaccine. Neutralizing antibodies to bovine herpesvirus 1 were not found in nasal secretions but were present in serum 7 days after vaccination. Bovine herpesvirus 1 was isolated before challenge from nasal secretions of calves vaccinated intranasally or i.m. with virulent virus but not those vaccinated i.m. with vaccine virus. Evidently, both routes of vaccination with either virulent or attenuated bovine herpesvirus 1 provided protection from challenge with homologous or heterologous bovine herpesvirus 1 and live vaccines should contain at least 103 plaque forming units/dose for effective immunization.