EXPERIMENTAL REPRODUCTION OF ENDOCARDITIS WITH PASTEURELLA-GALLINARUMIN MATURE LEGHORN CHICKENS

The pathogenicity of Pasteurella gallinarum for mature leghorn chicken s was investigated by inoculating thirty 52-week-old chickens intraven ously with live P. gallinarum. Each chicken was inoculated once daily for 5 days at one of three different dosage levels with either the typ e strain ATCC 13361 or a field isolate from a chicken with endocarditi s. Chickens were necropsied after death or euthanasia. Valvular endoca rditis was present. in seven chickens given the field isolate and five chickens given the type strain. Other lesions detected were myocardit is, hepatic and splenic infarcts, nephritis, pneumonia, and encephalit is. At necropsy, P. gallinarum was reisolated from hearts, livers, spl eens, lungs, kidneys, and blood. Controls injected with sterile broth had no lesions of endocarditis, nor was P. gallinarum isolated from th em. The results confirm the pathogenicity of P. gallinarum for the hea rt valves of mature chickens.