The problem: The gastrointestinal tract of the horse is not designed to process large amounts of starch and sugar in its hindgut. From a physiological perspective, starch and sugar are best digested in the small intestine. However, when the small intestine becomes overwhelmed and cannot process a deluge of starch and sugar it passes on to the cecum and colon (collectively known as the hindgut).

Digestion of these nutrients in the hindgut causes a disturbance in the resident microflora population, leading to a decrease in environmental pH and a condition called hindgut acidosis. If severe enough, hindgut acidosis can lead to irritated mucosa, causing signs of unthriftiness and unhappiness: inappetence, weight loss, mild diarrhea, sourness, and development of stable vices such as cribbing or wood chewing.

Hindgut acidosis is prevalent among horses that must consume large grain meals to fuel intense exercise, as well as those that graze fructan-rich pastures.

The solution: Acidosis is not a health concern unique to horses. Researchers involved in dairy cattle realized that erratic eating patterns caused by swings in rumen pH affected milk production, which ultimately reduced profits. Researchers and dairy producers successfully manage ruminal acidosis by adding a buffer such as sodium bicarbonate. With this research as a premise, Kentucky Equine Research (KER) scientists set out to find a solution to managing horses with hindgut acidosis. The task: supply a buffer to the hindgut that minimizes fluctuations in pH when significant quantities of starch and sugar are consumed.

The technology: The greatest obstacle in designing a buffer for the hindgut involved the architecture of the gastrointestinal tract. Unlike cattle, fermentation of forages occurs in the hindgut of the horse, not the foregut, so researchers at KER developed a way for the buffer to withstand passage through the harsh environments of the stomach and small intestine to reach its target organs. The result: EquiShure, a time-released hindgut buffer created specifically for horses, is a novel and effective way to combat signs of hindgut acidosis. Horses fed EquiShure have reinvigorated appetites, elevated feed efficiency, and improved performance.

Published Research

• Feeding protected sodium bicarbonate attenuates hindgut acidosis in horses fed a high-grain ration