Diarrhea in Horses

Diarrhea is loose unformed excess water in the stool. In horses diarrhea is not a disease but a symptom. It is caused when something disrupts the balance of microbes in the colon. In such a situation the water is not absorbed in the colon and is lost as it is passed out with feces. If this goes on for a long time it can get very serious. The horse will end up getting dehydrated and ultimately die if not treated in time. On the other hand if the horse suffers from mild diarrhea it will pass soft manure and that is not usually considered a problem.
Diarrhea could be caused due to a number of reasons. Some of them are; changes in feed or over feeding the horse. It is considered to be one of the most common reasons why a horse gets diarrhea. Always remember any change in the feed or grain should be slow and gradual. Foods such as hay and grass are processed in the large intestines. In order to process this food it requires the presence of some amount of microbial organisms. A sudden change in the feed results in diarrhea as the number of organisms required is not sufficient. When the quality of the diet is inadequate it could also lead to diarrhea. Always check the feed to make sure that the fat has not gone rancid or there is no mould or bacterial overgrowth on it.  When buying feeds make sure the ingredients don’t have generic terms like ‘grain products’ as different batches may have different ingredients. This will result in rapid feed change. Sand Colic is another cause of diarrhea. This occurs when a horse eats hay of the ground or grazes on short shrubs. Small amounts of sand can be ingested at this time and accumulate.

The veterinary diagnostics for horses with diarrhea includes a careful history and physical exam.  Laboratory tests on both the blood as well as manure are taken depending on the case.  A few precautions horse owner can take in order to prevent diarrhea are:

• Avoid any sudden changes in the diet.
• Insure that it has fresh water all the time. Do not rely on stagnant and contaminated ponds, streams and ditches.
• Always have an appropriate parasite control program.
• Use antibiotics only when necessary and after consulting your veterinarian.
• Always communicate with your veterinarian if you notice diarrhea in an adult horse, before it becomes a severe problem.