Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose

Foal or Newborn, Necrotizing Enterocolitis, Bloody Diarrhea

Synonyms: Clostridium Enterotoxemia, Clostridium perfringens, Clostridium dificile Colitis


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.

my vet's role


The prognosis is guarded to poor, even with aggressive treatment and nursing care. There are several syndromes- some have a better prognosis than others. The worst is C. dificile necrotizing enterocolitis, in which the whole intestine can be overwhelmingly damaged.

As with many disease processes, early recognition and aggressive treatment provides the foal the best chance for survival.

Chances of survival are better at veterinary school and large private practice neonatal ICU units with the staff to provide round-the-clock care. Most severely affected foals often will require total intravenous nutrition for extended periods of time.

my role


I might observe

You might make these observations when a horse has this condition.

Very Common
Less Common
more observations

Questions To Ask Your Vet:
  • Are my other foals at risk?
  • How can I prevent this in future foals?
  • How much will treatment cost?
  • What is the prognosis for this foal?

Since this disease is so difficult to treat, prevention is the key. Disinfect foaling quarters carefully. Wash the mare's udder with mild detergent and water, ideally 24 hours prior to foaling. Remove the accumulated smegma from between the mare's udder halves. If its possible and practical to bathe the mare the day or two prior to foaling, that will further reduce the likelihood of foals ingesting the bacteria as it searches for the udder for the first time. Be sure to rinse soap off well.

It's important to ensure good general health and husbandry to reduce the likelihood of this infection. Keep turnout paddocks clean. Vaccinate pregnant mare with Clostridium C&D antitoxin. Another potentially effective preventative is to give Clostridial C&D antitoxin by mouth to newborn foals as directed by your vet. A prophylactic course of metronidazole may also be recommended for high risk foals.

Related References:

Madigan JE, Manual of Equine Neonatal Medicine 4th edition. on IVIS www.ivis.org.

Author: Doug Thal DVM Dipl. ABVP