My Horse Has Guts!

No, we are not talking about bravery, but the horses digestive system - in particular the foregut .  What does the anatomy of the foregut look like? How  does our feeding routines play a huge role with a horse’s digestive system ? Its important that we understand how it all works and how we can help function best

Function of the Equine Foregut

Did you know that the foregut only accounts for 37% of the horses digestive system? The foregut includes the esophagus, stomach, and small intestine. A horse’s stomach only accounts for 10% of the capacity of the digestive system, approximately 9 to 15 liters.  At this point, you may be thinking how modern feeding schedules are not advantageous to a horse’s relatively small stomach.  We have adjusted our horse’s lifestyle so that it is easier for us, not them.  Rather than mimic their natural feeding habits (small meals, numerous times a day), we feed two or three large meals.  Large meals can hinder digestion.

Food that enters into the foregut is digested enzymatically.  This means that an enzyme (pepsin) is mixed with the food once it enters the stomach.  Pepsin allows proteins to be digested.  Additionally, hydrochloric acid in the stomach breaks down large food particles.  A horse has natural protective mechanisms, found in the mouth, against hydrochloric acid.  When a horse chews, the food is mixed with saliva.  The saliva  is comprised of bicarbonate, (similar to baking soda) which acts as a buffer against the hydrochloric acid once the food reaches their stomach.

Food travels from the stomach to the small intestine. The majority of digestion takes place in the small and large intestine, NOT the stomach !  Once the food is digested in the small intestine, absorption begins.  The walls of the intestine absorb nutrients from digested food, then blood carries it to the cells that need it most.

Feeding the Foregut

Large meals hinder digestion.  Small, frequent meals are superior to large meals spaced hours apart.  For example, a horse who is fed grain in the morning and 4 flakes of hay may finish eating within a few hours.  While the horse is eating, bicarbonate from the saliva is mixing with their food, buffering the acid in the stomach.  Once the food has been eaten, it spends very little time in the stomach (as little as 15 minutes!).  Therefore, the stomach is empty, but the acid still remains.  Without further forage, the stomach has no buffer to help reduce the possibility of damage to its mucous lining.

Horses digestive system and gastric ulcers

Understanding the horse’s digestive system can help us understand why gastric ulcers may occur and how feeding routines can either help or hinder a horse’s health.