Joe Pagan, Ph.D., founder and president of Kentucky Equine Research (KER), gave the first talk of the 17th KER Nutrition Conference. His talk, titled "Energetics: Choosing an Appropriate Fuel for the Performance Horse," emphasized the importance of energy selection for equine athletes. Horses can use various fuels to drive locomotion: fat, glucose, and glycogen from the liver and muscle.
Various factors affect the type of fuel used such as breed, exercise intensity and duration, type of feed, and time of feeding.Dietary sources of energy were reviewed with emphasis on carbohydrates: hydrolyzable group (simple sugars, sucrose, certain starches), rapidly fermentable group (pectin, galactan, and gums, which can be considered "beneficial;" and undigested starch from cereals and fructans from pasture, which can be considered "not beneficial"), and slowly fermentable group (plant fiber compounds).
Pagan also reviewed other energy sources. Protein supplies energy for a performance horse, but it is not an ideal fuel because it causes excessive production of body heat as well as a higher level of nitrogen in the urine, which can make stalls malodorous.
Fat as an energy source has increased in popularity over the last several years. Although it is not a usual part of the horse's natural diet, horses use added fat well. Benefits include increased density of a ration, improvement in hair coat, and, in some horses, a decrease in excitable behavior. Horses adapt well to fat as an energy source. Pagan cited a KER study in which horses performing endurance exercise became acclimated to a high-fat diet in five weeks.
Fats rich in omega-3 fatty acids are preferable to other fat sources. Benefits of omega-3 fatty acids include decreased body-wide inflammation, decreased osteroarthritis, decreased allergic hyperactivity, and increased bone formation, among others. Fish oil is the gold standard for providing omega-3 fatty acids to diets. Supplementation of omega-3 fatty acids may have a capacity to increase flexibility of red blood cell walls. Increased membrane fluidity might decrease the incidence of exercise-induced pulmonary hemorrhage.
Pagan discussed feeding horses grain meals relative to time of exercise. Feeding grain two to three hours before exercise is undesirable. It is advisable to wait five hours after feeding grain before starting exercise.
Pagan reiterated the importance of meal size, feeding no more than five pounds of concentrate at one time. This reduces the risk of colic, laminitis, and hindgut acidosis. The absolute need for forage in the diet was underscored. An intake of 1.5-2% of body weight was recommended.