Proliferative Enteropathy (Foals) in Horses

Proliferative Enteropathy (Foals) in Horses - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost

Most common symptoms

Anemia / Diarrhea / Lethargy / Poor Appetite / Swelling / Weight Loss


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Most common symptoms

Anemia / Diarrhea / Lethargy / Poor Appetite / Swelling / Weight Loss

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Proliferative Enteropathy (Foals) in Horses - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost

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What is Proliferative Enteropathy (Foals)?

Proliferative enteropathy, also known as equine proliferative enteropathy or EPE, is a disease that affects primarily recently weaned foals and young yearlings. It is a disease that was first reported in 1982, transmission believed to be via the fecal/oral route. Equine proliferative enteropathy (EPE) has been found across the globe in places like North America, South America, Africa, Australia and Europe and presents a serious life-threatening situation for your horse and, potentially, to your herd.

Proliferative enteropathy (foals) is an intestinal disease which affects foals from birth to approximately 8 months of age. It is bacterial in nature and, in the weanling foal, can advance quickly to a severe stage.

Symptoms of Proliferative Enteropathy (Foals) in Horses

As noted above, this is a potentially life-threatening disease for your young foals which is able to be passed to other horses who come into contact with contaminated feces. Here are some of the symptoms which you might see in your foal, although they may be quite mild:

  • Depression
  • Loss of appetite
  • Fever greater than 101.3 degrees F or 38.5 degrees C
  • Swelling or edema between the front legs
  • Lethargy
  • Mild to severe diarrhea
  • Weight loss
  • Colic

If you note any of these symptoms, either alone or in any combination, call your vet immediately because, if left untreated, these symptoms can quickly progress to a more severe case.



The typing of proliferative enteropathy has to do with the species in which the disease is occurring. It is caused by the lawsonia intracellularis bacteria and has the capacity to cause similar symptoms in a variety of animal species, with swine being the most frequently afflicted animal species. Other species having been found afflicted with l intracellularis bacteria are hamsters, rabbits, fox, deer, ferrets, ostriches and non-human primates, with many of the symptoms being similar to those in afflicted horses.

Causes of Proliferative Enteropathy (Foals) in Horses

Proliferative enteropathy in foals is caused by the colonization of the bacteria called lawsonia intracellularis and is spread through the fecal/oral route. This means that infected animals become infected via contaminated water and feed and the bacteria sets up residence in the intestinal system of the animal. Susceptibility to the disease is increased in the following circumstances:

  • Weaning
  • Transportation
  • Overcrowding
  • Decreased colostral antibodies - the first milk secreted by the birth mother

  • Dietary changes

There are several animal species who are known to be carriers of the bacteria with their bodies being virtual reservoirs of the bacteria, transmitting it wherever they deposit their feces:

  • Rabbits
  • Dogs
  • Cats
  • Mice
  • Rats

The bacterium gets ingested from contaminated feed or water and it then finds its way to the small intestine where it can grow unchecked, changing the chemistry of the cells it infects. The cellular changes continue to spiral and thickening of the intestinal walls occurs, where protein and fluid loss begins and increases to dangerous levels for the host. As the disease progresses, the foal does not gain the necessary weight to mature properly. As the proteins and fluids continue to decrease, so does the health of the foal, with the above symptoms becoming more exaggerated in a relatively short period of time.

Diagnosis of Proliferative Enteropathy (Foals) in Horses

Diagnosis by your veterinary professional will include:

  • A thorough and complete history from you, the owner 
  • Clinic observations and examinations 
  • Abdominal ultrasound to determine if the intestinal walls are thickened
  • Blood work which will measure blood proteins and albumin levels
  • Lawsonia Intracellularis culture/serologic and fecal polymerase chain reaction (PCR) data
  • Intestinal biopsy
  • Histopathology - tissue analysis

Once these test results have been obtained and a final diagnosis developed, an appropriate treatment plan will be developed. However, some differential diagnoses will need to be ruled out before that treatment plan can be developed:

  • Salmonellosis
  • Clostridiosis
  • Neorickettsia risticii
  • R equi
  • Parasitic infections of various types
  • Any cause of infiltrative/inflammatory bowel disease

Confirmation of the diagnosis will be obtained when conditions respond to treatment. If there is no response to the attempted therapy, the vet should immediately reassess the diagnostics to check the diagnosis again. Emphasis is placed on immediately as the progression of this disease can be deadly for the foal.


Treatment of Proliferative Enteropathy (Foals) in Horses

Treatment for proliferative enteropathy is one of an antimicrobial variety. Since the the root cause is bacterial in nature, your veterinary caregiver will likely need to prescribe something like oxytetracycline 6.6 mg/kg intravenously twice daily for 3 to 7 days followed by a regimen of doxycycline 10 mg/kg orally twice daily for 14 days. Milder cases have been found to respond to the doxycycline alone. Alternative treatment regimens would likely consist of erythromycin alone or coupled with rifampin for 3 to 4 weeks or chloramphenicol. If the case is very severe, transfusions of plasma may be necessary. 

Glucocorticoids are not recommended as part of the treatment plan. Other components to the appropriate treatment plan will be dependent upon the severity of the disease and the condition of the foa in question and your veterinarian will take all options into consideration in the best treatment of your foal.

Recovery of Proliferative Enteropathy (Foals) in Horses

It would be prudent to expect confirmation of appropriate treatment to result in improved attitude, appetite and weight gain within the first week of treatment but improvement in the blood protein levels and small intestine changes will take longer, perhaps 4 to 8 weeks. It is estimated that about 90 percent of the afflicted foals survive. There is concern in regard not just to this afflicted foal, but also to any others in your herd. 

Though the development of the disease is sporadic, this disease can be spread to young yearlings and eventually to adult horses so it is in your best interest to adopt some routines which will limit the exposure of your herd to the bacteria. Here are some things to consider in terms of prevention:

  • Vaccination of your horses and other livestock
  • Avoid housing any pigs on your property near where you house your horses
  • Maintain good control over rodents

Again, if you note any of the symptoms, either alone or in any combination, call your vet immediately. The sooner the disease is diagnosed and treatment begun, the better the survival chances for your foal.

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Proliferative Enteropathy (Foals) Average Cost

From 336 quotes ranging from $1,500 - $5,500

Average Cost


Proliferative Enteropathy (Foals) Questions and Advice from Veterinary Professionals

Proliferative Enteropathy (Foals) Average Cost

From 336 quotes ranging from $1,500 - $5,500

Average Cost