Abstract
Pathological and bacteriological examinations were performed on two farm cows, aged seven years, suffering simultaneously from panarteritis and Klebsiella mastitis. Their mastitis had been treated with ampicillin, cloxacillin, and cefazolin. The affected udder quarters were swollen and indurated. There were several necrotic lesions on the cut surfaces. In histological terms, panarteritis in various stages was detected in small and medium arteries throughout the bodies of both animals. In one animal, IgM antigens were present in some affected arterial walls. Mastitis was characterized by extensive coagulative necrosis with edema and fibrin thrombi in the interstitial tissues and by fibrinopurulent inflammation in the mammary ducts in and around the necrotic lesions. Klebsiella pneumoniae was isolated in pure culture from udder lesions in both animals.
