These are several variations on deadly bacterial infection that causes diarrhea and severe illness in the newborn foal. They can affect multiple foals on a premise and tend to recur year after year. The Clostridial organisms are highly persistent in the environment and may survive for years. It is thought that the foal ingests the bacterial spores prior to the first ingestion of colostrum. Bacteria proliferate within the intestine, producing potent toxins that damage the gut wall and cause life-threatening illness.

This disease is a major killer of foals within the first few days of life. The onset is extremely rapid. A foal may be healthy one day, severely ill the next day, and dead the following day. Unlike some of the other conditions, it often affects apparently healthy foals that have had successful passive transfer (IgG>800).

Signs include colic and profuse diarrhea (often bloody). Foals rapidly stop nursing, act depressed, may show signs of colic and abdominal distention (bloating), and rapidly go into shock.

Diagnosis requires confirmation of bacterial toxin presence in foal feces, usually through PCR tests on feces. Bloody diarrhea in this age foal usually is taken as presumptive evidence of Clostridial disease.

Treatment is very difficult. Even with intensive care, these foals are very difficult to save. The intestine is often severely damaged.