Horses have evolved over millions of years as grazers, with specialized digestive tracts adapted to digest and utilize diets containing high levels of plant fiber.

Foals have a long gestational period (about 320 days) and are precocious at birth, standing and nursing within 20 minutes to 1 hour after birth.

Hindgut acidosis is a common problem in horses consuming large quantities of either grain or fructan-rich forages. This dietary regimen may lead to shifts in hindgut acidity when a portion of the grain starch is not digested in the small intestine. Passing into the cecum and colon, the starch is rapidly fermented, changing the environment […]

Feeding protected sodium bicarbonate attenuates hindgut acidosis in horses fed a high grain ration Pagan JD , Lawrence TJ , Lawrence LA , Huntington PJ Australian Equine Veterinarian 27(3), 53, 2008. Proceedings report of this research available here.

This study was designed to determine the effects of fat adaptation on carbohydrate and fat oxidation in conditioned horses during low-intensity exercise.

Hoffman RM, TM Hess, CA Williams, DS Kronfeld, KM Greiwe-Crandell, JE Waldron, PM Graham-Thiers, LS Gay, KE Saker, PA Harris. 2002. Dietary grain and endurance exercise. J. Anim. Sci. 80 (Suppl 1):171.

Every equine practitioner appreciates the delicate nature of the equine gut. Problems related to the
small intestine and large intestine are well understood and routinely treated. What may be surprising to many is how often the stomach is affected.

Mineral requirements for horses are usually calculated using information about
the horse’s body weight, age, weight gain, physiological status (pregnancy, lactation,
etc.) and level of activity.This paper will review some of the most important factors affecting the
digestibility of minerals in horses and will use data from a series of digestion trials
conducted by Kentucky Equine Research to illustrate how relevant nutrient interactions
are in typical horse rations.

The effect of aluminum supplementation on nutrient digestibility and macro- and micromineral balance was studied in balance trials in mature Thoroughbred horses. It is concluded that short-term consumption of a diet containing 930 ppm aluminum has negligible effect on nutrient digestibility and mineral metabolism in horses.

Very little research has been conducted to determine the trace mineral requirements for athletic horses. The objectives of this study were to
1) determine the digestibility and retention of copper, zinc and manganese over four different levels of intake (basal, 50% of NRC added, 100% of NRC added, and 200% of NRC added) and 2) determine how regular exercise and training alters the requirements for these trace minerals. Results of the present study suggest that exercise training results in a higher requirement for Zn, but does not affect the true digestibility and maintenance requirements of Cu and Mn in mature Thoroughbred horses.