A Case of Verrucous Endocarditis Due to Fusobacterium necrophorum subsp. necrophorum in Japanese Black Calf

Abstract

An 8-month-old Japanese black calf died on the 12th day after the initial consultation for pneumonia. Necropsy revealed verrucous endocarditis in the mitral valve, a hepatic abscess and a pulmonary abscess. Bacteriological examination isolated Fusobacterium necrophorum subsp. necrophorum from these lesions. Histopathological examination revealed gram-negative rod bacilli in valvular endocarditis encapsulated in the liver, and pulmonary abscesses. F. necrophorum is a common pathogen for suppurative disease in fattening beef cattle, however, only one case of bovine endocarditis was reported during meat inspection in the slaughterhouse. This case features valvular endocarditis due to F. necrophorum subsp. necrophorum in the left atrium and mitral valve.