Forages can often meet a horse’s energy needs.
Feed no more than 0.5 percent of your horse’s bodyweight in cereal grains at one time.
You can add fat to the diet through feedstuffs naturally high in fat or supplemental fats.
You should slowly make increases in diet fat content.
Avoid feeding excess fat to prevent obesity in your horse.
All horses need carbohydrates in their diets. But the type and amount of carbohydrates they receive can affect their health.
Present in forage, cellulose is the most common carbohydrate in horse diets. Microbes in the horse’s hindgut break down cellulose into individual sugars. As a byproduct, they produce volatile fatty acids. Horses use these acids as their main energy source. Often, a horse’s energy needs can be met solely by forages.
Cereal grains, like oats, corn and barley, are high in starch. Enzymes, produced by the horse, digest starch into individual sugars in the foregut. Horses can then use these sugars for energy if they need more energy than forages can provide alone.
Careful attention to the amount of starches you feed your horse is key to their health.
In general, feed no more than 0.5 percent of your horse’s bodyweight in cereal grains at one meal. For example, a 1,000-pound horse should receive no more than 5 pounds of grains at one time. If you feed more than this, you risk serious health issues from overflow of starch into the hindgut.
If you feed too much starch it will overflow into the hindgut. Microbes will then use the starch for energy and produce byproducts that make the hindgut more acidic. This acidic environment alters microbe populations and the integrity of the lining of the hindgut. Both of these changes can harm the horse’s health and lead to laminitis and founder.
Fat is dense in calories and provides a good source of energy for the horse. Combinations of common feedstuffs in a horse’s ration likely contain 3 to 5 percent fat. Horse’s can easily use up to 20 percent fat in their diet.
You can replace some of your horse’s grain with fat or add extra energy to their diet with fat. Horses that will benefit the most from this include horses exercised intensively, older horses that have trouble keeping on weight and horses that have foundered before.
Always slowly increase the fat content of your horse’s diet. It takes about three weeks for a horse to adapt to a high fat diet.
No reports show harmful effects from feeding a high fat diet to horses for an extended time period. But, make sure you don’t provide excess energy in the diet, which will result in an obese horse.
Feedstuffs naturally high in fat
Adding feedstuffs naturally high in fat (e.g. rice bran or flax seed) can increase fat content in a horse’s diet. Make sure to account for the other nutrients these feedstuffs add to the ration.
Supplemental fats include vegetable oils, hydrolyzed animal fats and dry granular fats. These sources contain more than 98 percent fat and don’t add other nutrients to the diet.
Vegetable oils tend to be more palatable than animal fats and have a lower chance of containing impurities. The most common method of increasing fat content in a diet is to top dress grain with corn or soybean oil.
Reviewed in 2018