What is a hallmark pathological finding associated with bacillary hemoglobinuria in cattle?

• A. Hemoglobinuria and hepatic infarct
• B. Diarrhea and dehydration
• C. Pulmonary edema
• D. Renal failure

Answer: (A)

The main idea is that bacillary hemoglobinuria in cattle is defined by intravascular hemolysis causing hemoglobin in the urine, together with hepatic infarcts from toxin-mediated liver necrosis. Clostridium haemolyticum produces toxins that destroy red blood cells and damage liver tissue, so you see dark, hemoglobin-rich urine and focal hepatic necrosis (infarcts). This combination—hemoglobinuria plus hepatic infarcts—is the characteristic finding.

Other options don’t reflect this hallmark. Diarrhea and dehydration are more typical of enteric diseases; pulmonary edema isn’t a feature of bacillary hemoglobinuria; renal failure can occur as a consequence of hemoglobinuric processes but isn’t the defining lesion.