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FIBER
are now thought to be a ‘coping mechanism’ in response to a stressful situation. Recent work has found a clear relationship between gastric ulcers, cribbing, and meal feeding cereal-based diets to horses. While there is little evidence to show that stereotypic behaviors actually impair performance, they are an indication that the horse finds its environment unacceptable, and this is a serious welfare issue.
A new generation of feeds Happily alongside the research into the negative effects of feeding cereals to horses, scientists have investigated ways of supplying more energy and protein using novel ingredients, many of them byproducts of the human food industry. Many of these feeds are fiber-based, as research has shown that gut health and general wellbeing is facilitated by feeding horses what they have evolved to eat i.e., fiber. While not advocating that all racehorses should be fed fiber-only diets – as those doing predominantly sprint work will need to have some cereals to replenish muscle glycogen stores – most racehorses would benefit from having a large proportion of their cereal feed replaced with high-quality fiber feeds. Feeds containing sugar beet pulp, alfalfa, chopped grass, citrus pulp, or soya hulls are all useful substitutes for cereals. Many of these high-fiber mixes, nuts, and
chops have energy and protein contents similar to cereals and so supply equal levels of nutrients to a traditional ‘hard-feed.’ Because these are fiber-based feeds they are digested in the hindgut, producing short chain fatty acids (acetate, propionate, and butyrate) that are readily metabolized to energy.
“Recent work has found a clear relationship between gastric ulcers, crib-biting, and meal feeding cereal-based diets to horses.” Evidence to support feeding fiber to racehorses Recent work by Swedish researchers Jansson and Lindberg (2012) has shown that racehorses fed all-forage diets had similar performance levels but lower blood lactate and higher venous pH post-exercise than those fed a cereal and forage diet. These measurements indicated that the horses were able to perform more aerobically, which increased time to fatigue and reduced stress and recovery time. Giving horses
bicarbonate (milkshake) has been a common practice in the racing industry to counteract the effects of acidosis induced by intensive exercise. The raising of venous pH on the all-fiber diets fed in this study showed that this effect can be achieved naturally by feeding fiber. While no digestive parameters were measured here, other studies have shown that fiber reduces gastric ulcers, so there are several welldocumented reasons to increase the fiber in racehorse diets. Fiber feeds naturally have better mineral, vitamin, and electrolyte profiles than cereals and in a form that is readily available, so the horse can utilize these micronutrients more efficiently than those in cereals. Mineral imbalances can cause bone, muscle, and nerve problems in horses while electrolyte loss is a major cause of fatigue, so a natural source of these nutrients presented in a palatable form is highly desirable.
Energy demands Those racehorses galloping over longer distances have higher total energy demands than those doing short sprints. Short, very fast races are mostly run anaerobically and for this the horse uses glucose and muscle glycogen as fuel. However, a high proportion of racehorses run longer distances and like all other athletes they use a combination of anaerobic and aerobic energy. As the research above indicated, feeding a substrate
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