When the stomach remains empty, the excess gas produced can cause rupture of the stomach, leading to death. The optimal method to feed horses is to allow for continuous consumption. The small intestine is the main site of both digestion and nutrient absorption. As with the stomach, the level of feed intake influences flow rate of ingesta through the small intestine. Large amounts fed per meal increases rate of flow to the large intestine.
Liquids pass to the cecum as quickly as a few hours after ingestion.
Within 2-4 hours, any feed not digested and absorbed in the small intestine is passed on to the cecum and colon. Because the horse's digestive system is designed so grain carbohydrates and proteins are digested in the upper gut, it is important to feed relatively small amounts, two to four times each day, for safer, more efficient digestion. If more is needed, divide it into two to three feedings. Together, the cecum and colon make up about 50 percent of the volume of the digestive tract. The cecum and colon house the bacterial, protozoal and fungal populations which function in microbial digestion of fibrous feeds, such as hay or pasture.