CHRONIC DIARRHEA

General Information

Chronic diarrhea is diarrhea that recurs intermittently or persists for longer than 2 weeks. The manure has a “cow pie” to watery consistency. Some normal horses occasionally pass a few ounces of liquid after a normal bowel movement; this can dirty the tail but should not be confused with chronic diarrhea.

Causes

Chronic diarrhea has various causes. They include reaction to a specific feed or pasture, intestinal parasitism, sand eating, bacterial or protozoal overgrowth in the bowel, granulomatous enteritis, long-term use of non steroidal anti inflammatory drugs, chronic liver disease, and intestinal cancer (such as lymphosarcoma). Some cases have no apparent cause. The longer diarrhea has been present, damage to the bowel makes it less likely that the horse will recover.

Diagnosis

Diagnosing the underlying cause of chronic diarrhea is often done in a sequence of steps. If a diagnostic procedure does not reveal the cause of the diarrhea, we move on to the next step in the diagnostic process. The typical steps in diagnosis are as follows:

• Initial blood tests and fecal examinations: These are done to assess your horse’s condition and to detect some of the more serious causes of diarrhea.
• Intestinal absorption tests: These are done to evaluate the intestine’s ability to absorb nutrients.
• Fectal biopsy: This is done to evaluate changes in the bowel lining.
• Exploratory surgery: This is done to examine the abdominal cavity to detect abnormalities that may be causing diarrhea.