Blackleg in a Beef Calf

A dead four month old heifer calf was submitted to the lab. The calf was part of a group of 30 cow/calf pairs on pasture.

Picture 1. four month old heifer calf

Picture 2. pleuritis and congested thymus

Necropsy examination revealed pleuritis and congested thymus,

Picture 3. diaphragm muscle

Picture 4. peritonitis



Picture 5. splenomegaly
a dark area of ventral diaphragm muscle with adjacent peritonitis, and splenomegaly

Picture 6. pleuritis

There was also pleuritis affecting the thoracic wall between the ribs and pericardial sack. Fluorescent antibody examinations were positive on diaphragm muscle for Clostridium chauvoei, and anaerobic culture of diaphragm demonstrated Clostridium chauvoei. Microscopic examination of diaphragm revealed severe diffuse necrotizing myositis. Here is a recent newletter with more information on blackleg.