There are many possible causes of diarrhea in a horse, some of which are not too serious and are easily treated. However, it is important not to ignore this symptom in your equine friend, as it could be a sign of something much more dangerous—or even deadly.
A sudden change in diet can cause a horse to have diarrhea. Many horses have sensitive stomachs, and quickly altering the foods they eat can have a nasty reaction. This is easily prevented in most cases; simply make any dietary changes slowly. Do not suddenly stop feeding one type of food in exchange for another or switch types of hay without giving the horse time to adjust. Make the change slowly by incorporating new food, while weaning the horse off of the old stuff, in order to prevent such a shock to your horse’s digestive system.
Food allergies and sensitivities can also lead to diarrhea, so talk to an equine nutritionist or veterinarian if you suspect this may be the case, especially when introducing a new type of food to your horse’s diet. Also, make sure to feed high-quality foods; moldy hay or rancid grain can cause stomach upset, diarrhea and even colic, which can be life-threatening.
A horse that is stressed out may have diarrhea, as may a horse that has undergone heavy exercise. Its system may have overheated, or its digestive system went on overdrive, causing diarrhea. This is usually nothing to worry about, as long as it is not an ongoing problem. Provide the horse with plenty of water, and do your best to keep it calm. This may happen to a horse that goes to a competition and is in new surroundings. If in doubt, call the vet to be safe, especially if it continues after the horse is back in its own environment.
Parasites and Infections
If the horse has worms or any other type of parasite, it may end up with diarrhea. This is usually easy to treat by giving the horse a dewormer, which is given orally and kills parasites. Talk to your vet in order to put the horse on a deworming program in order to prevent future infestations and to find which type will best treat your horse.
Other infections, such as a virus or bacterial infection, can also cause diarrhea. Potomac Horse Fever or salmonella poisoning are just two examples, and veterinary intervention will be very important in order to treat these, as they could result in death. It is always a good idea to call your veterinarian if your horse has diarrhea, especially if you have not made any dietary or lifestyle changes that may have stressed the horse and resulted in runny stool. He can help determine if it is something serious, such as cancer, or something that is more easily remedied.
Precautions and Treatment
Diarrhea can be a symptom of something serious, so it is important to take great care in ensuring the horse is not seriously ill. Diarrhea also can make the horse dehydrated, so it is important to provide the horse with plenty of fresh, clean water. Electrolyte therapy may be necessary in some extreme cases in which the horse is severely dehydrated. This means the horse will have the lost fluids and nutrients, such as salt, replaced in order to help rehydrate its body and rebalance its salt levels.
Most cases of diarrhea are best treated by targeting the cause itself—such as deworming a horse with worms—and by regulating the horse’s diet and exercise routine. If you are unsure what is causing the diarrhea, or believe it may be something serious, do not hesitate to call your vet; it could save your horse‘s life.