An atypical case of actinobacillosis in a cow.

An atypical case of actinobacillosis with involvement of the skin of the right hind limb and its lymphatics was diagnosed in a cow. The granulomatous lesions were observed as several masses along the lateral part of the right hind limb. The right precrural lymph node was enlarged more than 10 times its normal size. Histopathological examination of biopsy materials revealed actinobacillus granuloma. Smears of granular pus obtained from the precrural lymph node showed a small number of gram negative bacilli.