Meet Bugsy. When he came into my life he was 25 years old, underweight and lethargic, with creaky, painful joints. Living in the mountains of Colorado, the terrain was too hilly for him to venture much past the barn. An old stifle injury from his racing days left him stiff and reluctant to move. The pain, compounded by his new surroundings, made him distrustful and reserved.

Horses - Younger to older

Changes come about gradually, but as your horse starts to show signs of aging, the diet you've been feeding may now be obsolete and in need of an adjustment.
© 2017 by Dace Kirspile

But what Bugsy didn't know is that he came to the right home! After a few months of tender care and targeted nutrition, he was a new horse. He gained weight, had a twinkle in his eye, and showed the curiosity and warmth of a youngster. And best of all, he was running up and down the hills with ease!

Advances in veterinary medicine and greater attention to nutrition have made it possible, and even probable, that your horse will live well into his 30s and may even reach his 40s. Individuality plays as much a role in the way horses age as it does for us. There are predictable changes, however, that go along with growing old.

Some horses have trouble gaining weight, others become too fat. Teeth wear down, making chewing difficult; some may even lose teeth. Most horses experience a decline in immune function and get sick more easily or develop allergies. Muscle mass may diminish, and joints can become stiff. Digestion and absorption efficiency declines.

All these changes come about gradually, but as your horse starts to show signs of aging, the diet you've been feeding may now be obsolete and in need of an adjustment.

Two major changes to consider

1. Saliva production diminishes. Dry meals can be difficult to chew and swallow, potentially leading to choke. This natural aspect of aging is easy to manage by simply adding water to your horse's feed; he'll appreciate having his meal a little on the mushy side. And be sure there is clean, fresh water close by that is temperature controlled during the cold months.

2. Digestion efficiency is not what it once was. This can lead to diarrhea, electrolyte imbalances, and weight loss. It starts in the small intestine and pancreas where your horse produces fewer digestive enzymes, potentially leading to nutrient deficiencies simply because his tissues can't receive the nutrients from his meal. Plus, undigested food is free to enter the hindgut where it is either fermented (which can lead to colic or laminitis) or ends up in the manure. Lastly, after years of exposure to harmful elements in the feed and environment, the horse may develop a leaky gut, leading to immune issues, metabolic irregularities, and oxidative stress throughout the body.

Important diet guidelines

Provide forage at all times. Forage needs to be available 24/7, all day and all night. This is not only necessary to prevent ulcers and colic, but without it, the horse will experience a stress-related hormonal response that potentially damages the brain. When the hypothalamus is inflamed due to stress, the horse can develop equine Cushing's disease, insulin resistance, and leptin resistance. Obesity is often the result.

The fix is simple -- allow your horse to be a horse and tell you how much hay he needs. He is very capable of maintaining a healthy body condition if given the chance.[i]

Choose the right senior feed

If you want to purchase a commercially fortified feed for your senior horse, your goals should include the following:

• Avoid GMO soy. Most of the soy grown in the U.S. is genetically modified to withstand being sprayed with Roundup® to control weeds. Any source of soy (soybean hulls, soybean meal, soybean oil, etc.) can potentially contain glyphosate (the herbicide found in RoundUp, which is damaging to your horse's health on many levels.[ii]
•  Even non-GMO soy can be inflammatory. Soy has a high phytoestrogen content as well as more omega 6 fatty acids relative to omega 3s. To correct for the essential fatty acid imbalance, high omega 3 feedstuffs can be added to the diet (such as ground flaxseeds or chia seeds).
•  Choose non-GMO or organic where possible.  Soy, alfalfa, corn, and beets are typically genetically modified; therefore, they are likely to contain glyphosate. Look for non-GMO on the label. But some crops such as wheat and rice, even though non-GMO, may be sprayed with glyphosate prior to harvesting to assist with drying. Consequently, a non-GMO designation may not be enough. Organic feeds offer the best assurance. There are feed companies, however, that are clean and glyphosate-free, even though they do not have an organic certification. It is always best to contact the feed company to gain more information.
•  Consider the sugar and starch content of the feed. Many clean feeds are high in cereal grains such as oats, barley, wheat, rice, etc., as well as molasses. Small quantities of these feeds may not be problematic, but if your horse is on a strict reduction of sugar/starch due to metabolic conditions (e.g. insulin resistance/metabolic syndrome, equine Cushing's disease (PPID), or PSSM), it may be worth choosing a feed that is not sweetened and is without added starchy feedstuffs.

Consider feeding a simple carrier-feed instead of a commercially fortified feed

If you are not feeding the commercial feed according to directions, your horse is not getting sufficient vitamins and minerals and you'll need to "supplement the supplement." Why not then simply feed a basic ingredient or two and add the necessary supplements? Here are some choices:

• Non-GMO beet pulp. Beet pulp is a good source of calories and is useful for underweight horses. It has about the same calories as oats, without the insulin response that starchy grains induce. High in water soluble fiber, it forms a soothing gel inside the hindgut. Best to rinse it first to remove excess iron, and then soak it for a few minutes (never overnight). Supplements can easily be added to this bulky feed.
• Non-GMO or organic hay pellets. These make excellent carriers for your supplements. Alfalfa pellets are tasty and offer additional protein from a source other than grasses, to boost the overall protein quality of the diet. Timothy pellets are a common choice, though many horses do not care for them. These pellets can be moistened into a mush making chewing easier and reducing the risk of choke.
• Chopped hay or chaff. This is especially pleasing for horses with poor teeth. They come in alfalfa, and grass mixes. Many products are sweetened, so be aware of that if your horse is insulin resistant. Here again, go for non-GMO or organic products.

Add digestive enzymes. Protein, carbohydrate, and fat digestion is mainly accomplished within the small intestine by enzymes (secreted from the small intestine and the pancreas). As horses age, production of these enzymes dwindles.

Adding a supplement that contains enzymes such as amylase, proteases, lipases, as well as microbial fermentation products, will help ensure digestion and absorption of key nutrients.

Feed the hindgut microbial population. These microorganisms are responsible for digesting fibrous portions of the diet, leading to the formation of volatile fatty acids to provide your horse with calories for energy.

They are also necessary for B-vitamin production and maintaining a healthy immune function. Their numbers can significantly diminish due to several causes, such as stomach acid reaching the hindgut because of an empty stomach or inadequate saliva production (saliva neutralizes acid), pain and mental stress, illness, antibiotics, or feeding GMO feeds (that may be sprayed with Roundup®.

Adding a prebiotic will help existing microbes maintain their numbers. A probiotic may also be useful, especially if your horse relies on hay as the main source of forage or has recently received antibiotics to treat an infection.

Remember that hay is deficient in many essential nutrients. Once healthy, living pasture grasses are cut, dried, and stored, they lose many nutrients, including essential fatty acids, antioxidant vitamins, as well as B vitamins. Therefore, it is imperative that you provide supplements to fill in the nutritional gaps found in a hay-based diet.

Here are my recommendations

• Provide a comprehensive vitamin/mineral supplement. Choose one that offers vitamins A, C, D, and E, as well as all 8 B vitamins (B1, B2, niacin, B6, B12, folic acid, pantothenic acid, and biotin). Copper, zinc, manganese, iodine, and selenium should be included. Avoid supplements that contain iron. There is plenty of iron in forages, and since forage in the foundation of the diet, adding more is not only unnecessary, but can create an imbalance with other trace minerals. In addition, iron exacerbates insulin resistance, so supplementation is not recommended for these horses.
• Include a source of essential fatty acids. There are two fatty acids that your horse cannot produce and hence, must be in the diet: Alpha linolenic acid (ALA) an omega 3, and linoleic acid (LA), an omega 6. Living pasture grasses, during their growing seasons, have approximately 4 times more ALA than LA. However, hay that has been stored for several months no longer has the levels of these essential fatty acids once contained in living grasses. Compound this with the fact that most commercial feeds use soybean oil as their source of fat, which is way too high in LA relative to ALA, resulting in increased levels of inflammation through the body. Therefore, to duplicate what is provided by natural living pasture, it is worthwhile to add a source of ALA such as stabilized ground flaxseeds or chia seeds.  ALA supports immune function, reduces the inflammation of aging joints and muscles, regulates blood insulin levels, promotes healthy skin and hooves, and improves attitude. ALA is converted to a more anti-inflammatory omega 3  known and DHA (found in fish oils and algae). However, the conversion rate is relatively small. Therefore, when treating more difficult cases of inflammation, it is best to add some DHA to the diet.
• Supplement vitamin C. Vitamin C is necessary for collagen production (protein found in bones, joints, and blood vessels). It is also a potent antioxidant and natural antihistamine. When young, your horse was capable of producing plenty of his own vitamin C. Now that he's getting older, his ability has diminished. He'll get ample vitamin C from fresh pasture, as long as it is growing and healthy; but hay has virtually no vitamin C. One caveat: If your horse has PPID or is insulin resistant, it is best to limit the amount of vitamin C added to his meal since vitamin C increases iron absorption. Too much iron makes insulin resistance worse.
• Supplement vitamin D during winter or when stalled. Your horse can produce vitamin D from sunlight but during the winter months or if your horse is not exposed to at least 8 hours of sunlight each day, be sure there is vitamin D added to your feed or supplement. This vitamin (along with vitamin C) will help keep your horse's bones, muscles, and teeth in top shape.
• Be aware of protein quality. If hay is your only source of protein, it is not of good enough quality to allow for maintenance and repair of tissues. The best way to ensure that your horse has a sufficient amino acid pool from which to build body proteins, is to offer a variety of protein sources. So, in addition to grass hay, consider adding alfalfa as well as whole foods. Some include hempseeds (the highest quality plant source), ground flaxseeds, chia seeds, black oil sunflower seeds (not too many since they are high in inflammatory omega 6), pea protein, whey, and copra meal (coconut meal). Avoid soybean meal unless it is organic, and only use in small quantities (no more than 1/2 pound) since it is inflammatory. Please note: Before adding protein to your horse's diet, be certain that his liver and kidneys are healthy. This can be determined by a simple blood test.

A few words about weight...

Many horses gain weight as they age. This may be a result of genetics, a sluggish metabolic rate, reduced activity, or a stress response from changes in living conditions or pain. If he has weight to lose, he doesn't really need anything other than pasture and/or hay, along with a small, low starch meal each day to serve as a carrier for supplements. But never restrict forage --  he needs to be able to graze at will 24/7, all day and all night. Going for hours without anything to eat will, ironically, prevent him from burning fat and he'll remain heavy.[iii]

The underweight horse can be very challenging.  First, try to determine the reason for weight loss. The most common cause in older horses is poor teeth. Other reasons include worm infestation, ulcers, infections, liver or kidney disease, and even cancer. Soaked hay cubes, non-GMO beet pulp, or chopped forage, fed free-choice, will meet forage requirements.

Extra calories are best provided by feeding high fat feeds. Ground flaxseeds, chia seeds, and hemp seeds are high in fat as well as essential fatty acids. Oils can also be added, such as hempseed oil, flaxseed oil, or camelina oi. Avoid corn oil, canola oil (unless it is organic), and certainly soybean oil (usually labeled "vegetable oil.")

Extra protein may also be a good approach. Hempseeds are of excellent quality and will help improve body condition. Finally, don't forget the microbes in the hindgut -- give your horse a good pre/probiotic with digestive enzymes. These organisms are responsible for deriving calories from fiber.

Pay attention to aging joints and muscles

Most, if not all, horses over the age of 20 will develop arthritis to some degree. Stall confinement makes arthritis worse and makes muscles tight. Mild exercise helps lubricate stiff joints and builds up surrounding muscles. Even if you don't ride your horse, the more pasture turnout he gets the better off he'll be. Nutritionally, consider the following additions to the diet:

• Vitamin C and omega 3s. Vitamin C helps build collagen and omega 3s reduce inflammation.
• Hempseeds and hempseed oil. Hempseeds contain an anti-inflammatory fatty acid, which is actually an omega 6, is called gamma linolenic acid (GLA).
• Turmeric. Curcumin, the active ingredient in turmeric, is excellent for pain and inflammation.
• Colostrum. Colostrum is a superior food that benefits joints, as well as immune function and digestive health.[iv]
• Joint supplements. These come in many varieties[v] and are worth considering.

Bottom line

Your horse's diet, amount of activity, environment, and stress level throughout his growing and adult years will influence how well he ages. Feeding a wholesome, clean diet, that fills in the nutritional gaps found in hay, will allow your horse to live a longer, more vibrant life.

By Juliet M. Getty, Ph.D.
[i] You are invited to read several articles in the Library at www.gettyequinenutrition.com. Articles are organized by topic : look at "Free Choice Forage Feeding" and "Overweight Horses," as well as "Leptin Resistance.
[ii] For a discussion on GMO foods and glyphosate, see Getty, J.M. "Non-GMO is not necessarily safe."  http://gettyequinenutrition.biz/library/nongmoisnotnecessarilysafe.htm. Also see Qizing, M., Manservisi, F., Panzacchi, et.al., 2018. The Ramazzini Institute 13-week pilot study on glyphosae and Roundup administered at human-equivalent dose to Sprague Dawley rats: effects on the microbiome. Environmental Health, 17(50). and  Van Bruggen, A.H.C., Shink, M.M., Mai, V., Jeong, K.C., et al., 2018. Environmental and health effects of the herbicide glyphosate. Science and the total environment, (616-1-7) 255-268.
[iii] See, "Respect the Power of the Horse's Instincts" under "Overweight Horses" in the Library at www.gettyequinenutrition.com.
[iv] Getty, J.M. "Colostrum: an exceptional superfood." http://gettyequinenutrition.biz/library/colostrumanexceptionalsuperfood.htm
[v] See a variety of joint preparations in Dr. Getty's Free Shipping Supplement Store: http://horsesupplements.gettyequinenutrition.biz/supplementsjointhealth.htm