Experimental infection of calves with Pasteurella multocida serovar A: 3 Isolated in Japan

Abstract

Pasteurella multocida, serovar A: 3, selected by pathogenicity in mice from among 10 strains isolated from pneumonic lesions of calves, was adjusted to 107, 108 and 1010 colony-forming units (CFU), and inoculated intratracheally into four calves. All calves showed pyrexia and had lungs with congestion and hepatization. Inoculation with 1010 CFU of bacteria produced respiratory symptoms and abscesses in lungs. This information will aid elucidation of the pathogenicity of P. multocida and the development of vaccines.