Immunogenicity of oil-based contagious bovine pleuropneumonia vaccine in cattle.

The effects on the immunity in cattle of dosage and storage of oil-based inactivated vaccine incorporating the Gladysdale strain were examined. Storage at 4 degrees C for 12 or 24 months was found not to have any marked effect on the immunity conferred in the vaccinated cattle. A dosage of 0.5 ml was found to be as effective as dosages at 1 and 2 ml of the inactivated vaccine. To assess the potency of the inactivated vaccine in cattle two methods were used: antibody response to the vaccine using the complement fixation test and the challenge test in cattle by contact using a virulent strain at 2 and 6 months after vaccination.