Can fat, a substance that's been given a bad rap, actually be good for your horse? So it would seem, from the buzz about the benefits of adding fat to the equine diet. You'll find powdered and pelleted fat supplements at your local feed store, and major feed companies are trotting out new high-fat rations right and left. Should your horse be in on the fat-feeding frenzy?
Fat isn't for every horse. If your critter is overweight, for example, it's probably the last thing he needs. But fat can be a real nutritional plus for many equines. To help you decide whether your horse could benefit, we turned to Gary Potter, PhD, a nutritionist at Texas A&M University who's researched the role fat plays in equine nutrition. With his help, we'll outline four common situations that may call for some extra fat or oil in your horse's feed bucket:
- A need to put weight on your horse.
- A need to add energy to his ration.
- A desire to improve his haircoat.
- Help for a horse that ties up.
For each case, we'll explain why fat helps, how to feed it, and what other steps you might take to address the problem.
Note: If you determine that your horse could benefit from additional dietary fat, introduce the fat source gradually to avoid upsetting his digestive system. Fat typically makes up no more than 2 to 3 percent of the food most adult horses consume, so your horse's system will need time to adjust to a higher level. Begin by adding 2 to 3 ounces a day, then build up in 2- to 3-ounce increments over a matter of days, until you reach the desired amount. Use the same type of gradual introduction with any fat source you choose.
Fat Supplement Reason #1 - Wanted: Weight Gain
The problem: Your horse is thin, but he's already getting a big grain ration. Grain is high in soluble carbohydrates-a great source of calories, but one with risks. You worry that increasing your horse's grain will put him at risk for laminitis (which has been linked to excessive amounts of soluble carbohydrates) and colic (caused by eating big grain meals and too little forage).
Why fat helps: Ounce for ounce, fat contains more than twice as many calories (that is, twice as much energy) as either carbohydrates or protein. So, fat gives you a way to increase your horse's caloric intake without increasing his grain ration to potentially dangerous levels.
Who benefits: A horse that's being fitted for show or recovering from an illness; an older horse that may not digest food as efficiently as he used to; a "hard keeper" that just can't seem to keep weight on; or any horse that's too thin.
How to feed it: Substitute fat for 10 percent of your horse's grain ration. For example, if your horse is getting 15 pounds of good-quality grass hay and 5 pounds of grain per day, reduce his grain by a half pound, and add a half pound of fat-a cup of vegetable oil, or the equivalent from another fat source. Top-dress or mix the fat with his grain, introducing it gradually, over a week or more. There's no need to change his forage.
Health check: While you're boosting calories through fat, ask yourself why your horse is too thin. Are you deworming him regularly? Do his teeth need floating? Is he sick? Work with your veterinarian to identify potential causes and correct them.
Fat Supplement Reason #2: Wanted - Energy Boost
The problem: Whether he's a reiner, a barrel racer, or an endurance horse, your equine athlete has high energy needs. To meet them, you may be giving him lots of grain-but there's a limit to how much grain you can feed him. (As a rule, grain shouldn't account for more than 60 percent of your horse's daily ration.) He may need more energy, but more grain will raise his risk of colic and laminitis.
Why fat helps: As it does for weight gain, fat gives you a way to boost your horse's energy intake without the risk of feeding him excessive quantities of grain. Fat may also help your horse do more work and be less fatigued. In research studies, Dr. Potter found that racehorses and cutting horses on a fat-supplemented diet were able to work longer and at a higher performance level than horses that hadn't been given a fat supplement.
Here's why: Your horse's muscles use energy in two ways-aerobically (with the oxygen he breathes in), for slow, steady work; and anaerobically (without oxygen), for bursts of speed and intense effort. To fuel aerobic work, your horse's body can call on fatty acids (components of fat) circulating in his bloodstream, and glycogen, a form of carbohydrate stored in his muscle cells. When his need for energy outstrips the ability of his heart and lungs to deliver oxygen to his muscles, his body kicks into anaerobic mode, when it must use glycogen. By feeding fat, you help ensure that your horse's body will have plenty of fatty acids for aerobic work, allowing him to save more of his glycogen reserves for intense effort. And here's a bonus: Burning fats for energy is more efficient than burning carbohydrates, as it produces more energy and less body heat. That makes fat a good hot-weather fuel.
Who benefits: Equine athletes in training, endurance horses, horses working in hot weather. Generally, it takes at least 3 weeks to see the full benefit of dietary fat on performance. Muscles seem to need to "learn" to rely on fatty acids first.
How to feed it: The 10 percent rule works here, too. For instance, if your horse is getting 15 pounds of hay and 10 pounds of grain, cut the grain by 10 percent to 9 pounds, and add 1 pound of fat-2 cups of oil or the equivalent from another source-mixed with or top-dressed on his feed. Make the change slowly-take a couple of weeks to work up to the full amount. (You can split it between morning and evening feedings.) Horses in very intense training (e.g., Olympic-level eventing) can use even more fat. But few horses need more, and it can be difficult to incorporate such high levels into the diet. (Note: When you add fat, regulate the amount of feed necessary to maintain your horse in the condition you want. If you're not increasing his workload and don't want him to gain weight, you may need to reduce the total amount of feed to keep him in shape.)
Health check: Supplemental fat is just one ingredient in the recipe for top performance. Work with your veterinarian to be sure your horse has a balanced diet and a training/conditioning program that will keep him fit for his job.
Fat Supplement Reason #3: Wanted - Glossy Coat
The problem: Your horse's coat is dull and lifeless, no matter how much you curry and brush it.
Why fat helps: One theory is that fatty acids, which are key components of fats and oils, help give the haircoat a glossy shine. Whatever the reason, fat is a traditional coat supplement and one that many trainers swear by.
Who benefits: A horse whose haircoat needs help, for show-ring pres-entation, or maybe just to counter the effects of sun and wind.
How to feed it: You'll need far less fat as a coat supplement than you will to boost energy or put weight on your horse. Two to 3 ounces of oil per day should do it. Divide the amount between his morning and evening meals, and top-dress or mix it with his feed. Or use a commercial supplement that contains fat, following label directions.
Health check: Fat alone won't make your horse's coat glow. A balanced diet, including protein and vitamins, is important for overall good health (which is reflected in your horse's coat), as is a regular de-worming and vaccination program. Work with your veterinarian to be sure your horse's lack of shine isn't a sign of an underlying problem. And remember-there's no substitute for regular, thorough grooming.
Fat Supplement Reason #4: Wanted - An End to Tying Up
The problem: Your horse suffers bouts of muscle spasms during or after exercise. In mild forms, tying-up syndrome (equine rhabdomyolysis) limits performance; in severe forms, it can be fatal.
Why fat helps: Many factors have been blamed for tying up, including vitamin E and/or selenium deficiencies, electrolyte imbalances, faulty regulation of calcium levels, or a buildup of lactic acid (a byproduct of anaerobic work) in muscle tissue. One idea is that, for some horses, tying up is caused by difficulty in using the carbohydrates from grain as fuel for muscles. Recent research has shown that many such horses improve
markedly on a diet in which 20 to 25 percent of their energy needs are provided by fat.
Who benefits: Tying up is a common equine disorder affecting many breeds. While complex causes may be at work, a low-carb, high-fat diet seems to help many horses that suffer from it. After several months on this diet, the muscles of affected horses begin to rely more on fat and less on carbohydrates for energy, and their symptoms decrease.
How to feed it: Decrease carbohydrates by eliminating as much grain as possible, and add fat to give your horse the energy he needs. One way to do this is to gradually replace grain with an equal quantity of alfalfa pellets, and mix in increasing amounts of fat until it makes up 20 percent of his daily calories. For example, a 1,000-pound horse in moderate work (which includes all but the most intense training) needs about 25,000 calories of digestible energy from all sources, including hay and pasture. A pound of fat-2 cups of oil-provides 4,000 calories, or about 20 percent of that. If he's not working, he only needs a total of about 16,000 calories a day; 11/2 cups or less will meet his needs. If he turns up his nose at the mixture of pellets and oil, try mixing in some rice bran or a commercial high-fat supplement in place of some of the oil.
Health check: Because tying-up syndrome is a serious and complex disorder, you should consult with your veterinarian before altering your horse's ration.
Elaine Pascoe is a Connecticut-based freelancer and Quarter Horse enthusiast.
This article first appeared in the June 2000 issue of Horse & Rider magazine.