Feeds and Supplements for Older Horses

Feeds and Supplements for Older Horses

Photo: Anne M. Eberhardt/The Horse

Equine nutritionists discuss a variety of feeds and feeding practices to help horses cope with the problems associated with growing old.

As horses grow older, their nutrient needs change. This might be due to bad or missing teeth, changes in metabolism, or less efficient digestion. Some horses become thin, while others gain weight and become prone to laminitis. Some develop problems such as Cushing's disease, insulin resistance, failing kidneys, or impaired liver function, and they need a special type of diet.

Importance of Balance

Amy Gill, PhD, an equine nutritionist based in Kentucky, says it is important for an older horse to have good-quality protein with the right amino acids. "Make sure the diet is highly fortified with vitamins and minerals, and very digestible sources of fiber," says Gill. Don't feed overly mature, coarse hay that's hard to chew and does not contain adequate nutrients.

In addressing feed needs of the older horse, we must define when a horse is "old," since horses age at different rates. You can't just say that horses past a certain age fall into the "old" category. Stephen Duren, PhD, an equine nutritionist with Performance Horse Nutrition in Weiser, Idaho, says there's an emotional definition of when a horse is old--when he retires from a career. He might be put out to pasture just because he's no longer being ridden regularly.

"There's also a nutritional definition of old, when he can no longer eat a normal diet and maintain body weight," says Duren. When the body starts to change, regardless of what is affecting it (teeth, Cushing's, or whatever), that's when you must think of the horse as geriatric and reconsider his diet.

Aging rate is affected by genetics and the lifestyle a horse has lived. "If he had good care all his life and was never used hard, 'old' may be mid-20s or early 30s," says Duren. "On the other hand, if a horse went to every branding and to team roping events every weekend and was used hard, he may be arthritic and have old injuries."

An older horse might lose weight because he's stiff and not as aggressive in the herd--he's dropped down in the pecking order and has been chased away from the hay. Dental problems and loss of teeth can also be a factor: In many ways a horse is only as "old" as his teeth. Some horses' teeth develop problems sooner than others.--Heather Smith Thomas

"In general, a healthy older horse that doesn't have metabolic problems has nutrient requirements a little higher than a mature horse in its prime," she says. "An older horse's requirements are very similar to those of a young, growing horse. Digestive efficiency is reduced in older horses. Like older humans, many of them get thin. They are in a more catabolic state-- metabolizing muscle tissue."

Thus, the old horse needs more feed, but it must contain all of his nutrient requirements; you should not increase calories just by adding more grain. He needs a concentrate with less grain and higher levels of soluble fiber and fat.

"Find a fat source that has a high omega-3 fatty acid, like a flax oil blend," Gill says. "This helps with immune response and is also a pro-anti-inflammatory," meaning prostaglandins (hormones that regulate cellular activites) produced in the body will tend to be the anti-inflammatory type rather than inflammatory. Omega-6 fatty acids (found in grains) tend to be pro- inflammatory.

She also recommends products containing small amounts of direct-fed microbials, such as yeast and Lactobacillis, since these are beneficial if the hindgut (the large intestine) is not functioning as well as it used to. Vitamins E and C are also helpful since they are powerful antioxidants, says Gill.

Avoid Starch and Sugar

Gill says the main thing to watch in older horses is that many of them are sensitive to starch and sugar; 70% of horses over age 20 have Cushing's disease. "If a horse has Cushing's disease or insulin-resistance problems, you can't just add calories to the diet with straight grain," says Gill. "We don't recommend that at all. If a horse is on hay, make sure there's not too much soluble carbohydrate or NSC (nonstructural carbohydrates) in the hay."

For a horse with Cushing's disease or insulin resistance, she recommends a lower-quality hay (fewer NSC) and supplementing with vitamins, minerals, and protein that the hay might lack. "You choose the lesser of two evils; you don't want a horse to not have anything in front of him to eat, so you use a lower-quality hay he can nibble on all day rather than a couple small flakes of good hay," she states.

A healthy horse can handle a better- quality hay, but you don't want to precipitate an insulin resistance problem by overfeeding starch and sugar.

"You can feed a good-quality, low-starch, high-fat and -fiber concentrate like a senior feed," says Gill. "But an important thing for horse owners to know is that even the senior feeds are not good choices for horses that are insulin resistant or have Cushing's disease. Even though it's a senior feed, it can still be very high in NSC. You need to look for a product that is low in NSC, so the total diet (forage and concentrate together) will be no higher than 10% NSC."

You must be careful all through a horse's life to make sure he does not become insulin resistant later on. "Don't overfeed the pregnant mare on starch and sugar, nor the foal, and on down the line," Gill warns. "It's like what we're hearing today in human nutrition. Our kids should be eating vegetables and healthy foods instead of sweets, so they don't have diabetes by the time they are 14 years old. It's wise to feed horses in a preventative manner also, rather than after the fact.

"One of the best products I've seen for older horses is Triple Crown Safe Starch, a complete mixed ration in a wrapped bale," says Gill. "It contains chopped forage (easy to chew) with pellets mixed in that contain all the protein, vitamins, and minerals. All you feed is this bagged product. The hay is grown specifically to have low NSC, and that saves the hassle of trying to figure out a diet for the older horse. Another product made by this company is called Low Starch, a pelleted concentrate that's easy to eat. A horse may need a combination of the two, or the forage product by itself may be adequate if the horse is carrying enough weight."

When making your own ration, have your hay tested and ask to see the NSC. Then you'll know if your forage is a good choice.

"If it's too high in NSC and you don't have any other options for hay, you can soak it in hot water for 30 minutes (then drain and discard the water) to pull out most of the sugar," says Gill.

Dental Issues

Stephen Duren, PhD, an equine nutritionist with Performance Horse Nutrition in Weiser, Idaho, says when you start planning a diet, start with forage (which, after the water requirement, is the most important element of diet for any horse).

"If an old horse, because of poor teeth, is quidding (dropping wads of partly chewed feed from his mouth) or not getting feed adequately chewed, we have to 'chew' it for him," says Duren.

An older horse that's not keeping his weight might not be getting enough fiber, says Kathleen Crandell, PhD, superintendent of Virginia Tech's Middleburg Agricultural Research and Extension Center. "The biting surface of his teeth may have changed and become wavy, or he's lost teeth and can no longer grind forage properly. He may do fine on green grass, but loses weight when you feed hay in winter."

This is when you need to use alternative forages such as hay cubes or chopped forages--something in which the breakdown process has already started (reducing particle size) so teeth don't have to do it all.

"Ultimately some horses need pellets containing forage that is ground up and doesn't need much chewing," says Crandell. "There are benefits in using chopped hay or hay cubes, since there's still some length in that material, which helps keep the digestive tract functioning more normally than with finely ground forage."

If a horse's teeth are so bad you must resort to pellets, soak them in water so they become a mash and fall apart. Then they are easier to eat (since cubes and pellets are often quite hard) and you've decreased the risk of choke, Crandell says.

Duren recommends completely covering the pellets or cubes with water so they soak it up and become soft. "Once the feed is fully moist, I don't add any extra water; the mass of pellets or cubes just grows in bulk as they take on water," he says. When using alternative fiber sources such as beet pulp, these are soaked also.

You can make a mash using hay pellets and add other things to it such as wheat bran or a senior feed. Again, forages are most important in the horse's diet, and a senior product alone might not be enough if it's the type that should be fed like a supplement.

Many people feed joint supplements to alleviate some of the discomfort of arthritis. "But you must be careful using glucosamine if you have an insulin-resistant horse or one with Cushing's disease, because glucosamine contains glucose," says Amy Gill, PhD, an equine nutritionist based in Kentucky. However, some veterinarians hold that the amount of glucose in glucosamine is insignificant in relation to the horse's total caloric intake, and that the possible benefits might outweigh any risk from the additional glucose.

Gill has been working with bioavailable silicon, which she feels has a beneficial effect on joints and soft tissue injuries and is a healthy supplement that does not change blood glucose levels.

Hyaluronic acid is also useful in older horses, according to Gill. Horse owners who use herbal remedies might try joint products that contain yucca.--Heather Smith Thomas

Senior Feeds

Senior feeds fall into two categories, says Duren. "One category is complete feeds that contain forage, grain, vitamins, and minerals all mixed together in a pellet, so particle sizes are small enough to be easily eaten," he says.

A horse can eat this product as the sole component of diet. Some companies recommend feeding a small amount of hay along with it, just to give the horse more to occupy his time, but these products are typically fed at 1.2-1.8% of body weight. They are very high-intake products, meant to be fed in large amounts.

"Many people use these products incorrectly," states Duren. "They've decided they have a senior horse (because of age or the fact he's retired from a career) and instead of feeding the proper amount, they just use it as a supplement or a treat."

Feeding a small amount does not give proper effect. Owners should note the recommended feeding rate that's on the label. Some senior feeds can be fed with additional chopped hay, hay cubes, or some hay or pasture, but you need to read the tag to know how a particular product should be fed. They are not all the same.

"The other type of senior product is mainly grain concentrate designed for older horses--they contain the grain, vitamins, and minerals needed for a horse that's still eating some hay," Duren says. "Feeding rate would be much lower than that of the complete feed."

Senior feeds are quite different from other supplements, however. "A concentrate for racehorses is mostly starch," says Crandell. "The senior feed has more fiber, at least 15% crude fiber and maybe as much as 20-30%. It might contain alfalfa meal, beet pulp, or some other high-fiber source."

This makes the feeding rate very important. If a product is meant to be a total ration to replace all or part of the forage, it cannot contain minerals in high concentration because you're feeding a lot of volume, and you don't want to overdo the minerals. Many people think that if they feed a pound or two of senior feed, they are fortifying their horse's diet with needed vitamins and minerals, but they are not, especially if the recommended feeding rate for that feed is eight or more pounds per day. You should not feed either product (complete feed or concentrates) incorrectly or the horse could develop a serious imbalance in vitamins and minerals (too much or too little).

"If you don't understand the feeding directions, there should be a phone number on the feed tag so you can call the company and ask questions," says Duren. "I would not buy a product unless I can call the company and find someone with the technical knowledge to answer questions."

The only way to get maximum benefit from any feed is to feed it properly. It is important to get feeding rate correct since other nutrients in a senior diet (vitamins and minerals) help stimulate the immune system in older horses, explains Duren.

An old horse might get thin toward spring. After he sheds his winter coat, you might notice he's thinner than he was last fall. "The horse didn't get thin overnight; it was a gradual process, going on all winter," says Stephen Duren, PhD, an equine nutritionist with Performance Horse Nutrition in Weiser, Idaho. The horse might have maintained himself on pasture, but not so well on hay.

"When feeding horses, we use body condition score of 1 to 9 (1 being emaciated and 9 being obese) to see where they fit," he says. "You want any horse to be at least a 5 (average body condition), and senior horses should be between 5 and 6 so they have a little reserve if weather gets cold or wet. But you don't want them 7 or 8, since obesity can also cause health problems. Carrying extra weight is harder on feet, legs, and arthritic joints, and may also make a horse more prone to founder.

"The only dietary factor you can observe and be correct is energy," he adds. "If you feed too many calories the horse gains weight; if you feed too few he loses weight. This is easy to see. Other diet factors are harder to determine. You can't look at a horse and tell whether he's deficient in copper or selenium, for instance, but being fat or thin is something you can do something about."--Heather Smith Thomas

Get Your Vet Involved

The wild card that horse owners might not expect is disease that can occur in older horses. "If the older horse is losing weight and it's not just a dental issue, it may be metabolic or a kidney or liver problem," says Crandell. Have your vet check the horse for proper diagnosis.

Sometimes cumulative damage from worms might make the digestive tract less efficient at absorbing nutrients. "After a certain point there may not be as much functional tissue," she says. "The horse may be able to keep his weight if you simply offer more feed."

But if it's a metabolic problem, the horse needs a different type of diet. Veterinarians can now diagnose most of the disease problems in older horses, and we can help them live longer by feeding special diets.

Gill says you need to make sure you know what you are dealing with so you can feed the horse properly and not make his condition worse: "Cushing's disease is a pituitary disorder, whereas the insulin-resistant horse just can't handle starch and sugar. A normal horse can handle limited amounts of starch and sugar, and you don't have to be quite as careful. But with many older horses you may be sitting on a time bomb, so it doesn't make sense to feed a lot of starch and sugars and then later have a problem."

If the horse just has trouble utilizing feed, senior feeds or high-fiber complete feeds in cube form can be helpful. Crandell explains, "If it's a weight issue, a high-fat/high-fiber feed can help supply needed calories. But if a horse has liver problems, you can't feed a high-fat diet."

It's wise to request a thorough exam and a blood panel if a horse starts losing weight, rather than just adding fat to the grain or more grain to the diet. Horses with Cushing's disease become prone to laminitis, and you need to reduce the amount of starch and sugars (or lush green grass) they consume. If the horse is at pasture for exercise, you might have to use a grazing muzzle.

Gill recommends having your vet draw a blood sample once a year to see if the horse is deviating from his normal baseline regarding liver and kidney function. If these organs are impaired, you'll need to work closely with your veterinarian and a nutritionist to design the best kind of diet and monitor the horse's condition.

Take-Home Message

Older horses have their own set of problems, from physical disorders such as Cushing's disease to issues as simple as bad or missing teeth. There are ways to feed these horses to supply their daily requirements, but all problems cannot be addressed the same way or with the same feed. Consult your veterinarian and equine nutritionist to develop a feeding plan best suited for your older companion.

About the Author

Heather Smith Thomas

Heather Smith Thomas ranches with her husband near Salmon, Idaho, raising cattle and a few horses. She has a B.A. in English and history from University of Puget Sound (1966). She has raised and trained horses for 50 years, and has been writing freelance articles and books nearly that long, publishing 20 books and more than 9,000 articles for horse and livestock publications. Some of her books include Understanding Equine Hoof Care, The Horse Conformation Handbook, Care and Management of Horses, Storey's Guide to Raising Horses and Storey's Guide to Training Horses. Besides having her own blog, www.heathersmiththomas.blogspot.com, she writes a biweekly blog at http://insidestorey.blogspot.com that comes out on Tuesdays.

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