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Equine Health Resource

Equine Proliferative Enteropathy, EPE

Synonyms: Lawsonia Intracellularis, Proliferative Ileitis, Intestinal Adenomatosis

This is a recently recognized bacterial infection often found in growing horses, usually under a year of age. It is a well known disease in pigs, and affects a variety of other species. It is found worldwide.

This bacteria affects the small intestine, which becomes chronically thickened and inflamed. This causes decreased digestion and absorption of nutrients.Affected foals tend to grow poorly, have poor body condition, have a pot-bellied appearance and rough coated.

Parasitism (worm load) or stress of weaning may predispose horses to developing this condition. The route of infection in horses is currently unknown, but it is believed that horses may be infected from ingesting contaminated feed or water or feces from an infected animal.

Treatment is with appropriate antibiotics. Many antibiotics are not effective against this bacteria and disease will continue in the face of treatment.

There is current research regarding the efficacy of a vaccine.


  • What is the latest research on diagnosis, treatment & prevention?
  • How can I manage my growing horses to minimize the incidence of this condition?

    This disease is considered permanently established (endemic) on certain properties, and returns year after year. In this case, talk to your vet about monitoring young horses in order to provide early diagnosis and treatment.

    There is research regarding the efficacy of a vaccine but currently a vaccine is not available.

    Author: Doug Thal DVM Dipl. ABVP


    Higgins AJ, Snyder JR eds. The Equine Manual. 2nd Ed. Edinburgh: Elsevier Saunders 2006.


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