Clostridium colinum is a fastidious, Gram-positive, rod-shaped, spore-forming anaerobic bacteria. C. colinum causes ulcerative enteritis (UE), which is a major clostridial enteric disease in chickens. Upon ingestion by the chicken, C. colinum adheres to the intestinal villi, producing inflammation and ulcers in the small intestine and proximal colon. Birds that recover from UE remain carriers and shed the bacteria in their feces. Outbreaks in chickens often accompany or follow coccidiosis, chicken infectious anemia, infectious bursal disease, or stress conditions.
Clostridium genus are found in many different environments (soil, sewage, water, animals and human gastrointestinal system) and are able to form endospores that allow them to survive in harsh environments for long periods of time.