Q. I am an avid event rider and enjoyed watching the Defender Kentucky Three-Day Event. What kinds of nutritional support can you give horses competing in this level of competition to help them recover?

A. This is a great question. Any post-competition recovery effort starts with the base diet, which meet the horse’s daily requirements leading up to the competition. No long-term deficiency is going to get fixed in the short period during competition, so a balanced diet appropriate for the horse’s discipline and work level is crucial.

Part of that is ensuring the horse is getting the right kind of fuel to support the type of work that he’s asked to do. Event horses won’t only be utilizing stored carbohydrate on cross-country day but hopefully their reserves of fat stores, as well. Cross-country efforts will deplete glycogen stores (stored carbohydrates) in the horse’s muscles. The horse will need glycogen again for the show jumping phase, so restoring those stores is an important component of recovery.

Horses don’t restore muscle glycogen after heavy work particularly quickly, however—it can take up to 72 hours to fully replenish this important fuel source. The tactics human athletes use—such as “carb loading”—don’t work particularly well in horses. Not only has research found carb loading horses relatively ineffective at increasing muscle glycogen, loading with carbs such as starch could lead to colic.

Hydration

One thing that does help improve glycogen replenishment is making sure the horse is adequately hydrated. Muscle glycogen requires water for storage, so a dehydrated horse is less able to generate new muscle glycogen stores.

Hydration measures should begin well before cross-county day. Many horse travel long distances to events, and these long journeys cause surprisingly large amounts of sweat loss. Even when you can’t see the sweat, horses can lose very high levels of electrolytes during transportation. This puts them at a disadvantage before the competition even starts. Feeding salt every day and adding a well-formulated electrolyte while traveling will help horses remain hydrated. Consider arriving a day early if travel is particularly long, so your horse has time to fully rehydrate and recover from the journey before competition starts.

Horses that drink saline solution after exercise have been shown to consume more water in the subsequent hours than those that drink plain water. Consider acclimating your horse to drinking water after work with either salt or electrolytes so this is a normal practice at events.

Muscle Recovery

Hard-working horses might be muscle-sore after cross-country, and supporting recovering muscle might help your horse come out on Day Three with a little more spring in his step. Vitamin E is an extremely important antioxidant for muscle health. Oxidation of glycogen and fats to create energy for muscle contraction causes the formation of free radicals. These oxidizing compounds are unstable and damage cell walls if not removed. Vitamin E helps stabilize them by donating an electron so that a cascade of free radical damage is prevented.

Horses need to get adequate vitamin E every day and, because of individual variation, some horses—even when receiving enough vitamin E to meet the National Research Council guidelines—are vitamin E-deficient. The best way to know your horse is getting enough vitamin E is to ensure his base diet is meeting the stated requirement. Then have your veterinarian test his serum vitamin E levels. This will tell you whether you need to supplement additional vitamin E daily. Providing extra natural vitamin E after particularly heavy work such as cross-country day might aid in recovery.

During recovery from exercise, muscle protein synthesis increases in order to repair muscle tissue damaged during work. If adequate dietary amino acids are available in the 24 to 48 hours post work, a net protein gain might occur. The most important amino acid for this process is leucine, which is a branched chain amino acid (BCAA). For this reason, administering a supplement that provides BCAAs after especially heavy exercise might help shorten recovery.

Take-Home Message

In general, after strenuous exercise, ensure your horse has access to good-quality forage (this is a safe way to replenish carbohydrates and encourages water intake), increase electrolyte intake to replace losses and encourage water consumption, ensure adequate natural vitamin E, and provide BCAAs. Incorporating these into your program will help your horse be at his best for the third day as well as recover from the overall event as quickly as possible.

Q. How long does it take for pasture grass sugar levels to drop after the sun goes down?

—Debra, Texas

A. The level of sugar in pasture grass varies due to several factors, including the weather, how stressed the grass is, its maturity, the time of year, and the time of day. As sun shines on pasture grass, the plants photosynthesize. This creates sugar stores the plan uses overnight to keep growing. Therefore, grasses tend to have higher sugar contents later in the day compared to earlier in the day.

Time Pasture Access Carefully

Generally, veterinarians and nutritionists recommend horses sensitive to sugar in pasture grass (such as those with insulin resistance, equine metabolic syndrome, or a history of laminitis) graze very early in the morning. It takes several hours after the sun sets for sugar levels to drop, so ideally try to avoid grazing before 3 a.m. And, because sugar levels start to build up again with sun exposure, it’s best to remove sensitive horses from pasture by about 10 a.m. If there’s significant cloud cover, you might be able to leave horses out a little longer, because photosynthesis (which relies on the sun) will be slower and therefore the amount of sugar will be lower.

One exception would be if the temperature drops below about 40°F overnight. At this temperature and below, the plants’ growth rate slow, which means stored sugars aren’t used up. As such, they’ll still be high in the early morning. In this situation, potentially at-risk horses should not have pasture access.

And, you must consider that some very sensitive horses might never be able to graze safely, while others can with careful grazing and pasture management. It all depends on the individual horse. Grazing muzzles are a very useful tool to help limit grass intake but still allow pasture access. Studies have shown that some muzzles can limit intake by as much as 80%.

Proper Pasture Management

Another important consideration is that most of the sugar in grasses tends to be in the bottom 3 to 4 inches of the plants. While it might be tempting to think that a very short, overgrazed pasture is safe because there’s “nothing out there,” such pastures present several risks—grasses are very stressed and only the lower inches of the plant are available, meaning these pastures can be very high in sugar.

As such, proper pasture management is very important to keep grasses from becoming stressed. This means horse owners need to properly fertilize and irrigate (if necessary) pastures.

It’s better for the plant and safer for the horse to stop grazing when the pasture has only about 3 to 4 inches of height left. This not only reduces sugar intake by your horse but also leaves some leaf for the plant so that it can regrow without having to dip in to root stores too heavily.

Take-Home Message

With an understanding of pasture grass metabolism and careful pasture and grazing management, many horses should be able to safely graze for at least part of the day. But, always consult your veterinarian or equine nutritionist before turning out your potentially sugar-sensitive horses on pasture.

Q: My horse will be turning 20 soon, and my barnmate told me I need to be more cautious about how I feed him vitamins and minerals to ensure I meet his daily requirements. Will his requirements change as he ages? Are there any specific vitamins he might become deficient in? 

A: Just as a human’s nutritional requirements change as they age, so will your horse’s; however, working with your veterinarian and an equine nutritionist can help you ensure he is getting the nutrition he needs during his senior years. 

Vitamin C can be particularly interesting for senior horses. In a study that looked at physiologic differences between young horses and older horses, researchers found that older horses had lower vitamin C levels overall. Of course, horses are a species, unlike humans or guinea pigs or any other animals, that can actually synthesize their own vitamin C, so we don’t know if horses just can’t produce enough vitamin C, or perhaps they use more of it because it is a pretty powerful antioxidant. This might mean that it’s necessary to supplement vitamin C if you have an older horse. 

Just like if a child ate too many vitamin C orange-flavored vitamins, oversupplying most nutrients, including vitamin C, is not a major concern because these can be excreted through the urine. However, there are some theories that oversupplying some vitamins, such as vitamin C, could inhibit the horse’s innate ability to produce them, making continued supplementation necessary. 

As horses get older, they might also become deficient in vitamin E and require supplementation, especially if they have little pasture available to them. When evaluating your horse’s vitamin E levels, it is important to analyze your horse’s diet. However, you can also ask your veterinarian for bloodwork to ensure that your horse’s vitamin E status is good.

Vitamin E is relatively safe, even in higher doses, but it can potentially prevent the absorption of other nutrients if overfed in excessive quantities. Ultimately, working with an equine nutritionist to regularly evaluate your horse’s diet, and with your veterinarian to test your horse’s blood levels will help ensure that they receive proper nutrition as they age. 

Q. This spring, I moved my horse to a new barn with grass turnout. My horse hasn’t been on pasture since I got him, and I’m unsure how to make this transition. I know it needs to be gradual, but how gradual, and how do I make it work?

A. I’m sure your horse will appreciate the opportunity to be turned out and have pasture access. But you are correct: Sudden dietary changes, whether it’s the introduction of grain, a hay change, or a move to pasture, can lead to colic and laminitis if done abruptly, whereas a gradual transition allows the digestive tract to adapt. The types and amounts of enzymes the horse’s digestive system secretes are diet-specific. This is also true of the bacteria composing the horse’s hindgut microbiome.

When equine diets change suddenly, feed components that should be digested and absorbed in the small intestine might not be. They might instead reach the hindgut, disrupting the microbiome microbial population. This can result in gas production, hindgut pH reductions (becoming more acidic), as well as die-offs of certain bacterial populations, causing toxin release. All of this can contribute to colic and laminitis.

Early spring pasture contains a lot of moisture, protein, and nonstructural carbohydrates (NSC). NSC includes sugar and starch, as well as more complex fructan sugars. High-NSC diets have two problems:

1. A sudden transition to a diet high in NSC can cause the hindgut disruption already mentioned, because sugar and starch that should be removed in the small intestine are not; and
2. For horses with metabolic issues such as insulin dysregulation and equine metabolic syndrome, NSCs can induce laminitis and founder.

To minimize hindgut disruption, a slow introduction to pasture is necessary, especially for sensitive horses with metabolic conditions. Understanding that these individuals might not be good candidates for any pasture is important. Before you embark on this project, make sure your horse is a good candidate for pasture.

If the barn manager expects pasture to provide real nutritional benefits, fields must be well-established before introducing horses. Putting horses on new pasture too early and before the plants are well-established can be tempting. Wait until the pasture has at least 6 inches of grass before grazing. A safe rule of thumb is that the bottom 4 inches always belong to the plant. If pastures are grazed below that height, you start to rob the plant of its ability to maintain itself, and ultimately your pastures will become overgrazed and plants will die, leaving bare patches and opportunity for weeds to take hold.

Assuming you have the minimum 6 inches of growth, introduce your horse to the pasture initially for just 15 minutes. This might require hand-grazing, because not all horses are going to want to come back inside after only 15 minutes on such a delicacy as spring grass! Then increase the grazing time by about 15 minutes every day until your horse is grazing for about four hours total. Stay at four hours per day for at least a week before granting unlimited access.

Clearly this process is labor-intensive, so it can be helpful to get creative about how you pull it off. The initial 15-30-minute periods can be fairly easily achieved before or after a ride. Allowing 15 minutes before a ride is a great way to get some forage in the stomach. If time is short, do your grooming while your horse grazes, or just hang out and enjoy his company. Then add some time after your ride as a reward. Schedule grazing so longer turnout periods happen on weekends or when you have more time. Ask a friend at the barn to help you out. With some teamwork and creativity, you can transition your horse to pasture safely.

Q. My horse gets frequent bouts of cellulitis. I work closely with my vet to treat and prevent this medically, but is there anything I can do to support our efforts through his diet?

A. Cellulitis is a bacterial infection that involves both the connective tissue and the fat tissue, most frequently presenting in the lower limb of the horse, and can be a challenging health issue. There are multiple causes of the condition; however, the infection normally enters the body through small (often undetectable) microtraumas on the skin surface.

Medical management is critical to resolving these cases, so it is great that you are working closely with your veterinarian. For treatment, the goal is to reduce the inflammation, eliminate the infection, and reduce the likelihood of the infection recurring.

A Balanced Diet for Horses With Cellulitis

Although nutritional management is not a cure for cellulitis, there are some dietary changes you can make to support your medical efforts. A balanced diet is imperative to maintaining both skin health and the immune system. Providing your horse with a feed or ration balancer (fed at the manufacturer’s recommended amount) is an important factor. Inadequate protein (amino acids), vitamin deficiencies, and unbalanced minerals can all negatively impact the health of a horse’s skin and hair coat, so pursuing a balanced diet for your horse with appropriate levels of vitamins, minerals, protein, and energy is important to promote optimal health.

Vitamin E & Omega-3s to Reduce Inflammation in Horses

When inflammatory issues are present, adding vitamin E and a source of omega-3 fatty acids is also a common recommendation. For your horse, if he is on a balanced diet, I recommend having his vitamin E levels tested via blood serum. If the levels are adequate, then there is no need for additional supplementation but, if he has a deficiency, supplementing with a natural source of vitamin E can help support your efforts to prevent cellulitis. 

When adding omega-3s, opt for a fat source that is greater in omega-3 content than omega-6 content (while one omega-6 type has been studied for its beneficial effects, omega-6s are generally considered to have pro- rather than anti-inflammatory properties; the ratio of the two seems to be what’s important). Oils such as flax or camelina are good options and can be fed at a rate of 1-2 oz per day to start and increased to 2-4 oz per day if your horse needs additional fat. Adding fat to the diet can help your horse maintain the protective barrier of sebum on his coat. This is especially important if your horse has dry skin and is prone to cellulitis. If your horse is not overweight, adding an omega-3-rich fat source to his daily ration can be a good way to support the prevention of cellulitis.

Digestive Support for Cellulitis

Because the cellulitis episodes are frequent, you could try a digestive support supplement for your horse. Regular administration of non-steroidal anti-inflammatory drugs (NSAIDs) and/or antibiotics can disrupt his gastrointestinal tract. Of course, a balanced forage-based diet will be a key factor in maintaining your horse’s gut health, but adding a pH control supplement for the gut could provide extra support. When choosing a supplement, evaluate the research on the product to ensure what you are investing in will support for your horse.

Take-Home Message

When cellulitis bouts occur, seeking medical management and guidance on optimal treatment from your veterinarian should be the first step. However, there are some nutritional considerations that can support your horse in addition to the medical efforts. A balanced diet that provides your horse adequate nutrients is imperative to his overall health. Adding a fat source that is rich in omega-3s and investigating digestive support supplements to use when your horse is on NSAIDs or antibiotics could reduce the negative effects these medications might have on his digestive system.

Do you have an equine nutrition question?

Q: This time of year, my horse’s mane and tail get very dry, and even his coat seems dry. I use coat conditioners when I bathe him, but I’m wondering what I could do nutritionally that might help?

A: If you live in a hot, dry climate, preventing a dry mane and tail and coat can be challenging. I find this to be especially true of horses living in dry lots or with dirt runs where they are basically rolling in dust.

Other than using topical products to try to maintain coat quality, the best you can do is to give the horse’s skin and coat a fighting chance by ensuring you’re feeding all the building blocks needed to maintain skin and coat health.

Minerals

Key nutritional players in this arena are zinc, copper, fatty acids, and biotin. Zinc is vitally important to a number of enzymes in skin. Epithelial cells that make up skin require zinc for reproduction, maintenance, and repair. Additionally the synthesis of keratins (proteins that protect epithelial cells and that are found in hair) and other associated proteins rely on zinc for proper function. While zinc is found in forages, the amounts present might not meet your horse’s needs.

Copper is generally in even shorter supply in forages than zinc. Copper is necessary for the enzyme lysyl oxidase, which in turn is required to maintain the structural integrity of the cross-linkages that provide strength to collagen in the skin.

Together copper and zinc impact melanin, the protein responsible for hair pigmentation. Therefore, inadequate copper and zinc status might not only impact the keratinization of hair but also its color. Hair is at greater risk of oxidative damage if melanin is inadequate.

If you’re just feeding forage, consider adding a source of copper and zinc that provides about half of the National Research Council’s daily requirement, which for a 1,100-pound horse is 50 milligrams of copper and 200 milligrams of zinc. My preferred method is using one of the quality ration balancing feeds and supplements available on the market because they also supply other essential nutrients that might be missing in a forage-based diet.

If you’re already feeding a commercial feed, make sure that you’re following the feeding directions and offering adequate amounts, otherwise your horse might have deficiencies in nutrients key to coat quality.

Fat

The cell membrane layers that connect the cells that make up hair contain large amounts of fatty acids. The fat in the cuticle cells make them hydrophobic, meaning they don’t attract water. This acts to make them waterproof but also keeps moisture in. Cuticle cells should lie flat like shingles on a roof, but if they become damaged, they peel away from the hair allowing internal moisture to escape.

Therefore, ensuring adequate amounts of essential fatty acids in the diet might help improve coat quality. I particularly like sources of supplemental fats that provide more omega-3 fatty acids than omega-6, such as flax or camelina. For coat improvement purposes, I find plant-based sources to be more than adequate, and about 4 ounces of flax seed or 2 ounces of the oils should be enough for you to see an improvement in an average-sized horse.

Biotin

While we typically think of biotin in relation to hoof health, biotin also plays a role in skin and coat. Biotin is a B vitamin that is actually made by the bacteria in the horse’s hindgut making biotin deficiency unlikely.

However, in other species inadequate biotin results in poor quality skin and coat. This makes sense when you consider that biotin involved in fatty acid synthesis, amino acid metabolism, and a range of other metabolic pathways. While there are no guidelines for how much biotin to supplement to see improvement in coat quality, research suggests 20 to 30 milligrams for and average-sized horse to aid in hoof quality and we can assume similar levels are necessary to see coat improvements.

Take-Home Message

Ensuring that your horse has the building blocks necessary to create a healthy coat from the inside is your best way to defend against a dry coat. However, make sure that you are not shampooing your horse too frequently as this can remove naturally occurring oils. Additionally, look for simple shampoos that contain few detergents and avoid those with alcohol as these can strip the oils from a horse’s coat.

Q: Can a nutritional imbalance or food allergy cause hives? My gelding broke out into hives after I started feeding him pure alfalfa hay, but when I switched him to Timothy grass hay the hives disappeared.

A: Owners often attribute itchy skin, hives, loose manure, and even behavioral changes as potentially being the result of food allergies, and they commonly presume alfalfa is the culprit. Whether these reactions are truly allergies—specifically food allergies—is often a point of debate. A food allergy is defined as an immune-mediated adverse reaction to food, where the body is reacting to a protein within that food or other substance, such as pollen. Allergies are reactions to substances that would not normally be problematic for most individuals.

Food allergies in horses do exist; however, most researcher and veterinarians consider them rare. If a horse has hives because of a food allergy, they would be expected to be all over the body rather than in isolated areas, which would point more toward a contact allergy from something like laundry detergent. The reaction might manifest as itchy hives or be solely in the gastrointestinal tract and result in clinical signs such as diarrhea.

Owners and veterinarians often reach for blood tests to diagnose allergies. These panels often include foods such as hays and common feed ingredients; however, research has shown that these tests are frequently inaccurate. The only true way to diagnose a food allergy is to do a withdrawal diet and then reintroduce the specific ingredients you believe the horse is allergic to. This takes time (often eight to 12 weeks) and dedication, and most owners are not willing to reintroduce ingredients that might be allergens, especially if the horse’s symptoms have resolved.

Horses can also have food intolerances or sensitivities, which are not immune-mediated reactions. They tend to present as loose manure and changes in behavior rather than hives, but hives could be present. Sensitivities might have a threshold such that the horse can handle the feed until consumed at a certain level. This is similar to lactose intolerance in people, where affect individuals might be able to consume small amounts of lactose in ice cream, but if they also eat a cheese pizza at the same meal, they show symptoms of their intolerance.

It is possible that your horse is not truly allergic to alfalfa and could handle alfalfa fed in smaller amounts, but a solely alfalfa hay diet causes issues for him. The only way to know whether that’s the case would be to add some amount of alfalfa back into the ration with the Timothy hay and see whether the hives return. This sensitivity threshold is likely why many horses can cope with supposed problem ingredients when they are in relatively small amounts such as in supplements but cannot cope with them when fed in greater quantities.

Another component of managing allergies is horses with allergies tend to be allergic to multiple things, such as insect bites and certain pollens. If you can control even a few of the allergens the horse is exposed to, you might eliminate or reduce allergic symptoms. So, if you can remove certain allergens that are easier to control from the horse’s environment, the horse might be able to handle exposure to other allergens, such as feed ingredients, without issue.

Q: I’ve always enjoyed giving my horse a warm bran mash in cold weather, but this doesn’t seem to be something people do much anymore. Is there still a place for wheat bran in my feed room?

A: Growing up I routinely fed a warm bran mash to my horse in the winter, especially on days when he worked hard. However it’s far more unusual now in part because we’ve realized that it might not be as beneficial as we once believed.

In my 1983 8^th Edition of the British Horse Society and The Pony Club Manual of Horsemanship it states that a bran mash is a “very useful warm food after hard exercise and hunting.” It goes on to say that after adding boiling water to the bran, you should add a generous amount of salt along with some oats, and then feed once cool. It finishes by saying “bran mash has a laxative value, and it has everything to recommend it when fed once a week to horses in work and to invalid horses. It is also a convenient way to administer medicines such as worming compounds.”

So how did a feed and feeding practice that were once so popular fall out of favor? To better understand that you need to understand your horse’s digestive tract, as well as the composition of the feed.

About Diet Changes and Digestive Tract Upset

Most of us are well aware that changes to a horse’s diet should be made gradually over several days. The reason for this is that the digestive enzymes, the amount secreted as well as the bacteria in the horse’s hind gut, are somewhat specific to the diet being fed. Therefore, if you change the makeup of the diet the enzymes and digestive bacteria must adapt, and this takes time. In the meantime if too much new feed is fed the horse might not be able to fully digest it and can lead to digestive disturbance (e.g., diarrhea, gas, and colic, etc.).

As previously mentioned, horse people used to routinely feed bran mashes once a week, largely for their believed laxative effect. Since becoming more educated in equine nutrition, it’s fascinated me that—while we take great care not to suddenly change a horse’s diet when starting most new feeds—this logic goes out the window when it comes to a bran mash. Essentially, when you feed a bran mash once a week you’re breaking all the guidelines you typically follow in keeping your horse’s diet consistent. The “laxative effect” might be because the feed change is causing digestive distress! This is probably not the best method of ensuring your horse’s digestive contents stay on the move.

Wheat Bran’s Nutritional Imbalance

Wheat bran has also fallen out of favor because of its high phosphorus level. In fact wheat bran has an inverted calcium to phosphorus ratio, meaning that it contains more phosphorus than calcium. This is actually common in traditional grains such as wheat, oats, and barley. However, wheat bran is particularly high with a phosphorus content of about 1% and calcium at only 0.15%.

Researchers realized feeding diets with a lot of wheat bran increased the risk of developing secondary hyperparathyroidism, a condition that results from a calcium imbalance potentially caused by horses consuming a diet too high in phosphorus. “Big head” or “bran disease” was far more common when horse owners and managers fed traditional grains and wheat bran more commonly than we do today. In reality this condition is unlikely to result from feeding a bran mash once a week. It’s far more likely if bran or traditional grains are fed daily in a poorly balanced ration. Traditionally any number of unfortified grains could have caused a similar issue, but because, proportionally, brans add much more phosphorus per pound than the grains, they are often considered a larger problem. With the concern over big head and potential links to bran, much less wheat bran is now fed and most rice brans are fortified with additional calcium carbonate to neutralize the problem.

So, What’s Right About Bran?

Going back to the quote from my Manual of Horsemanship, if a bran mash has “everything to recommend it,” what’s it doing right, given the two already discussed areas of concern? First, the manual hints that bran mashes are generally welcomed by even the most picky eater. Often, after very long and heavy work such as fox hunting, horses might have a reduced appetite and the goal is to get the horse eating and the digestive tract moving. Some sick horses that have gone off feed can be tempted to eat with a bran mash. Therefore, a bran mash can be a very useful tool when faced with a horse that has gone off feed and will not eat anything else.

Second, adding salt to a bran mash is a great practice, especially when fed after work that might have incurred heavy sweat losses.

Alternative Warm Mashes for Your Horse

So, when you want to give a bran mash is there something else that might be more beneficial? Is there a better way?

If you already give your horse supplemental feed, whether it is pellets or a textured feed, add hot water to make a warm mash just as you would with wheat bran. This way you are creating the mash but using familiar feeds that are less likely to irritate the gastrointestinal tract.

If you only feed forage, purchase some hay pellets that are like the forage you feed and use them to make a mash.

Next add some salt, or if you already give salt every day and your horse has been sweating heavily, add an electrolyte. If you need to entice a picky eater or a horse that has gone off feed, try adding carrot or apple peelings. If you have your heart set on a weekly bran mash, then I suggest adding a small amount of bran to your horse’s every day feed so that the mash is not a novel feed to your horse’ digestive tract. But be careful to keep the amount of bran small and consider discussing with an equine nutritionist how to add bran to your ration while maintaining a balanced mineral profile.

Q. I feed my ulcer-prone horse alfalfa before riding, because I’ve heard the calcium in alfalfa works like a big Tums antacid to keep my horse’s stomach from hurting during exercise. I was recently told that alfalfa pellets don’t work and that I should use alfalfa hay or chop instead, because the alfalfa needs to create a “hay mat” in the stomach to keep acid from splashing up into a horse’s esophagus (basically, causing horse heartburn). Is it true that I need to feed alfalfa hay or chop instead of pellets?

A. You are correct. Alfalfa is typically high in calcium, which researchers have shown reduces stomach acidity due to its buffering capacity. In a study at Texas A&M University, 12 horses were assigned to one of two groups: a 1:1 ratio by weight of Bermuda hay and a concentrate feed or of alfalfa hay and the same concentrate feed.

Treatment periods lasted 28 days before horses switched to the other diet with a 21-day washout period between treatments. At the start of the study each horse went through a gastroscopy to determine whether they had gastric ulcers and, if so, their severity. Horses were rescoped after the 28-day treatment periods to determine whether any existing ulcers had improved or worsened or new ulcers had appeared.

The researchers found that ulcer severity scores were significantly lower when horses ate alfalfa hay compared to Bermuda hay. Feeding alfalfa prevented ulcer formation in 11 of 12 horses that did not have ulcers initially, whereas only three of the 12 horses that did not have ulcers stayed ulcer-free when fed Bermuda. The team attributed these results to alfalfa’s higher calcium and protein content providing greater buffering capacity. The complex carbohydrate fractions found in alfalfa’s cell walls have also been shown to provide better buffering than those found in grass hays.

It’s clear that alfalfa does a good job of buffering the acid in the equine stomach. The question therefore becomes, does it matter what form the alfalfa is in? Long-stem hay requires a good amount of chewing before being swallowed, and chewing results in saliva. Equine saliva contains a good amount of sodium bicarbonate, which will also buffer stomach acid. Pellets take less chewing so result in less saliva and lower buffering from the bicarbonate. So long-stem hay would be preferable from that perspective. But what about the fiber mat?

The equine stomach is not completely full of acid. Large feed particles float on top of the acid, helping prevent it from splashing into the upper portion of the stomach where most ulcers occur. Pellets have a much smaller particle size than long-stem fiber, so alfalfa hay is more likely to make a better mat than pellets. Keep in mind that any forage in hay form—not just alfalfa—will form a good mat and cause saliva production. So if your horse has eaten hay within the few hours prior to your ride, he likely already has a good mat.

The calcium in pellets might buffer more quickly than hay due to the smaller particle size, but the smaller particles might also cause the calcium to move out of the stomach faster than larger particles would. So the question becomes: Which is more important, the hay mat or the buffering? If the stomach’s acidity is low, it won’t matter as much if the acid splashes into the stomach’s unprotected upper region. A hay mat is less important when the stomach acid is less acidic, and depending on when your horse last ate hay, a mat might already exist.

If you’re arriving to ride your horse and he has an empty stomach, and you give him alfalfa while you’re grooming, he might not have time to consume much alfalfa hay, because it requires more chewing. You might get greater buffering capacity more quickly by feeding pellets, although you won’t get a great mat. Most stomach buffers are relatively short-lived, lasting at most a couple of hours. Research has shown that some commercial buffers on the market buffer effectively and more quickly than alfalfa. These can be great options when given before exercise, if you need buffering capacity quickly.

Alfalfa’s ability to help reduce ulcers, and in which form you should use it, depends on a combination of complex interactions. The best solution for each horse might not be completely clear, but what we do know is that giving some form of alfalfa before riding a horse with an empty stomach will likely have a positive impact and could reduce your horse’s risk of developing gastric ulcers.

Q. I have an upper-level dressage horse that is in a rigorous training program six days a week. He is currently in good condition with a body condition score (BCS) of 5. Because he is working hard, I’m concerned about his protein intake. What are the best sources of high-quality protein for me to look for or add to his feed?

A. Protein is an important part of your horse’s diet and is one of the six required nutrient classes for horses. Taking a keen interest in your horse’s protein intake is important because when a horse’s workload increases, his or her protein requirement increases as well.

Proteins are a major component of body tissues and play key roles in enzymes, hormones, and antibodies, so consuming a quality protein source is imperative to working horses’ health. Protein is also necessary for muscle development and repair, which is necessary for horses in work.

Amino Acids in Equine Diets

Protein molecules are composed of amino acids. There are 21 main amino acids, 10 of which are essential, meaning the horse cannot synthesize them and we must provide them in the diet. The National Research Council’s (NRC) Nutrient Requirements of Horses, published in 2007, provides a recommendation for horses’ crude protein intake as well as lysine intake. Lysine is the first-limiting amino acid for horses, meaning it is the first essential amino acid in which they become deficient. Although equine researchers do not yet know how much of each essential amino acid horses need, we know that lysine, threonine, and methionine are the first three limiting.

High-quality protein is readily digestible for the horse in the small intestine if the protein source is providing the essential amino acids in correct amounts. A lower-quality protein source might not provide the key amino acids or be as digestible.

Evaluating Protein Content in Your Horse’s Diet

Before you focus on the protein in your supplemental products, you should first look at the hay, which almost always makes up most of the horse’s diet. If you are concerned about your horse’s protein intake, first order a hay analysis. Simply adding more protein to your horse’s diet without analyzing your hay first can eventually have negative effects on your horse’s health.

Excess and Deficiency in Equine Diets

In equine diets too much or too little protein can cause health issues. Performance horses maintained on high-quality hay with supplemental feeds are unlikely to have protein deficiencies.

Excess dietary protein is not typically an issue for healthy horses because they can break it down and excrete the excess, but it can put unnecessary strain on the kidneys and liver. Horses do not store protein for later use the way they do carbohydrates and fats.

When horses consume excess protein for a prolonged period, it can increase the horse’s heat production and urine output and create a significant ammonia smell in the stall that negatively affects the respiratory tract. Additionally, protein is a costly feed ingredient so providing it in excess makes the ration unnecessarily expensive.

Choosing A Quality Protein Source for Your Horse

When evaluating protein in the diet, look at the crude protein your hay and feed supply and evaluate the quality of the protein source. Hay provides protein to the horse, and legumes such as alfalfa serve as high-quality protein sources. Other high-quality protein sources include soybean meal, canola meal, flax, whey, sunflower meal, and a variety of legumes. Equine nutritionists typically regard cereal grains (i.e. oats or corn) as lower-quality protein sources.

When reading the label of the feed you have chosen for your horse, instead of just looking at the crude protein percentage, you should also take a close look at the ingredient list. Take note of the protein sources and be conscious of where they lie on the list. Ideally, the higher-quality sources should be at the top of the ingredient list, meaning they make up most of the product’s protein content. If the higher-quality sources are toward the end of the ingredient list, it indicates they make up a smaller portion of the feed’s protein.

Take-Home Message

The crucial first step in planning an optimal diet for your horse is to pursue a hay analysis, which will help you understand how much protein your forage is providing. This information will help you be confident you are meeting your horse’s crude protein requirement. From there, you can critically evaluate your horse’s feed to ensure there are high-quality protein sources in the ingredient list such as alfalfa, soy, canola, whey, legumes, or even sunflower meal. Choosing a commercial feed that mainly includes high-quality protein sources is a good way to ensure the product is supplying highly-digestible protein to your horse.

Q: My easy-keeper horse had laminitis a few years ago, and ever since then I have controlled his hay intake to ensure he maintains an adequate body condition score. My concern is his hay ration does not last him 24 hours, even with a hay net. I have heard that horses should not go without hay, therefore I am wondering what management tactics could help his hay last longer? And should I be concerned when his hay runs out?

A: It is great to hear your horse has maintained a healthy body condition (which should be 4-5 on the Henneke scale) after recovering from laminitis. As you know, it can be very challenging to manage these easy keepers.

You are correct in that it is important to ensure that horses do not have extended periods of time without access to hay. However, for horses that tend to be overweight, they are typically unable to have free-choice hay because this can result in obesity, which is a serious health concern. 

The Importance of ‘Trickle Feeding’ for Horses

The reason horses need access to hay or roughage for most of their time stems from how they have adapted to eat. Horses are trickle feeders and graze for upward of 18 hours per day. Therefore, their anatomy is designed to support trickle-feeding behavior. For example, unlike in humans, when horses chew, it stimulates salivation. Saliva is important for both moistening feed and as a gastric buffer, so it’s crucial to consider chew time when determining how to feed your horse his hay rations.

Additionally, the stomach continually produces gastric acid—even when the horse is not eating. Lack of forage in the horse’s stomach creates a much more acidic environment and can increase the risk of gastric ulcers developing.

There are many anatomical reasons to support trickle feeding, but it is important to keep in mind that obesity is also a serious health issue in horses. It is not always as simple as hanging a hay net and hoping our easy keepers can pace themselves.

How Much Hay to Feed an Easy Keeper

When restricting forage, you must still meet the minimum hay intake of 1.5% of the horse’s body weight daily. For example, a 1,100-lb horse needs to consume a minimum of 16.5 lbs of hay daily. Be sure you are implementing slow-feeding methods, such as hay nets, and offering multiple feedings so the horse is never without hay for longer than four hours.

If you have an easy keeper and he runs out of hay an hour or two before his next feeding, it is not a cause for concern if he seems content otherwise. However, if he is having any prolonged periods (three to four-plus hours) without hay then you might need to consider management changes such as feeding him more often. Additionally, if the horse is displaying unwanted behaviors—for example, wood chewing—during the hour or two he is out of hay, this is a sign that you might need to adjust your feeding schedule. In situations when labor is not easily available, there are a few different automatic feeders on the market that could be used as well.

Hay Quality for Horses With Metabolic Issues

A commonly overlooked aspect of feeding easy keepers is evaluating the energy content of the hay—that is, the calories it offers. If your easy keeper is running out of hay too quickly, testing it to evaluate the energy content should be the first step. Easy keepers should eat Grade 3 or 4 “utility hay” based on the American Forage and Grassland Council grade scale. This is hay that is lower in digestible energy, with acid detergent fiber (ADF) content of 41-45% and neutral detergent fiber (NDF) content of 54-65% on a dry-matter basis.

When we match the quality of the hay to our horse’s needs, it can make the management much easier. For example, with your easy keeper, if you source lower-energy hay, it might mean he can consume more without gaining excess weight, so his daily hay ration could last longer.

Straw as an Additive for Easy Keepers

Another management tactic for these horses is to incorporate some straw into their ration. Straw is the byproduct of cereal crops (what is left over after the grain is harvested). Horse owners can use it for easy keepers because it is low in nutritional value and, therefore, low in energy. Please note that due to straw’s low nutritional value, you should not offer it as the primary forage for a horse, but it can make up to 25% of their forage.

As with any diet change, introduce straw over a minimum of seven days so that the horse can gradually adjust and to reduce the risk of gastrointestinal upset. Another key consideration you should make for any horse, but especially those consuming larger amounts of indigestible fiber, is water intake. Be sure your horse is receiving adequate salt and has free-choice access to a fresh and clean water source.

The goal of either sourcing lower-energy hay or incorporating some straw into the ration is to increase the amount of roughage the horse can consume, which helps prevent any fasting periods and increases chew time without significantly increasing digestible energy intake. Test both your hay and straw prior to feeding it to your horse to be sure it is safe for them. If you are unsure of the safety of a forage source, consult a qualified equine nutritionist prior to feeding it.

Even with lower-energy forage, and incorporating straw, slow-feeding tactics are often still necessary. If you are using a hay net, and your horse is continuing to eat too quickly, you could reduce the hole size of the net, or even double-net the hay to slow him down.

Slow-Feeding Tactics

Anytime you implement a new slow-feeding tactic, for example, double-netting, observe your horses to ensure they can consume the hay. Occasionally, if it is too difficult for them, they could become frustrated and give up on trying entirely.

Each horse is truly an individual, so you might have to experiment with a few different types of hay nets or slow feeders prior to finding one that works best for your horse. As horses get used to eating from hay nets, they become more skilled with it, and you might be able to gradually work them to nets with smaller holes or double-netting. Slowing down their intake is important, of course, but also consider any ways in which you can increase your easy keeper’s movement. You can use hay balls or play around with the paddock setup. For example, using multiple smaller hay nets so horses must travel between them or even setting up a track system are great options to encourage natural movement.

Take-Home Message

Overall, carefully managing easy-keeping horses and those at risk of obesity is imperative for their health. However, it can be challenging to provide them with adequate roughage while ensuring they do not become overweight. So, if your horse is on a good slow-feeding program and you have tested your hay, rest assured that your horse will be fine if he runs out for an hour here and there. However, if he experiences prolonged fasting periods, investigate the various management tactics you can use to reduce his time spent without forage.

Do you have an equine nutrition question?

Q: I’ve struggled to build my horse’s topline. His loin is under developed despite being in regular dressage training. A friend at the barn suggested that I add whey protein to his diet. I am curious to learn if this is a good idea and why it might help.

A: Having a strong back musculature, or topline, plays an important role in your horse’s ability to carry you as a rider in a way that a) protects his spine and other tissues and b) allows him to successfully fulfill athletic demands.

Horses can struggle with topline development for many reasons and, while nutrition can play a role, it’s important to rule out other potential issues. For example, saddle fit and training methods can impact a horse’s ability to use himself correctly and, thus, develop strong musculature. Similarly, pain associated with joints or conditions such as polysaccharide storage myopathy might also have an impact. For this reason, I strongly recommend your veterinarian assess your horse to rule out any other issues before assuming it’s nutritional.

I also recommend body condition scoring your horse and make sure he’s not lacking in condition overall. If you determine that the horse is generally underweight, you’ll probably need to increase calorie intake, as this is likely contributing to your lack of topline. If however you determine that the horse generally has good fat cover, the ribs are covered, etc., but his topline is still underdeveloped, then this might be associated with insufficient dietary protein.

How much protein does a horse need?

How much protein a horse needs depends on the horse and the physiologic state. I rarely find a crude protein deficiencies in mature horses’ diets; they typically only require about 10 or 11% crude protein in their diets, which most forage sources easily meet. However young, growing horses require 12 to 14%, and this might pose more of a challenge to meet.

Most good grass hays can meet mature horse protein requirements and provide 10% or higher crude protein; alfalfa typically provides 18% or more. Grain hays such as oat hay can fall short, with an average crude protein of closer to 8%.

In reality, though, your horse doesn’t have a crude protein requirement, but rather an amino acid requirement. Amino acids are the building blocks that make up proteins, and there are 21 amino acids of which nine are essential for mammals (histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine with others being conditionally essential). An essential nutrient is one that must be provided by the diet because the animal can’t make that nutrient itself. Each protein contains a range of these various amino acids with some providing a greater proportion of essential amino acids than others. The greater the proportion of essential amino acids in a protein the better quality that protein is said to be.

In an ideal world the amino acid composition of the diet you feed would exactly match the amino acid needs for your horse. Unfortunately, we need more research in this area before we are close to this level of accuracy in equine nutrition, although other species such as swine and poultry, have feeds more along these lines. The amino acid provided in the lowest quantity compared to the animal’s need is said to be the limiting amino acid. For equine diets lysine is typically the limiting amino acid followed by methionine which is why you often see them being singled out on feed labels with guaranteed levels.

Diet Design Tips

Grass hay is made up of medium- or low- quality protein and does not provide a great deal of lysine. This is particularly an issue if you limit your horse’s hay intake. Alfalfa, on the other hand, provides more lysine, so its protein is considered to be of better quality. Many performance horse owners I work with believe that they see a benefit in their horse’s topline when they feed some of the forage ration as alfalfa, and this might be part of the reason.

Another complicating factor associated with hay protein is that the more mature a hay is, the more protein is associated with the structural carbohydrate fractions. This is potentially important because protein digestion and amino acid absorption needs to occur in the small intestine. However, structural carbohydrates require microbial fermentation to be broken down to release the protein contained within. Microbial fermentation occurs in the hindgut, which comes after the small intestine. Therefore, any protein and amino acids released at that point have missed the opportunity to be absorbed and instead are converted by the bacteria to ammonia. So, while a hay analysis can suggest a particular forage has adequate amounts of protein it’s possible that not all that protein is actually available for the horse. This is likely a bigger concern for grass and grain hays because alfalfa has so much more protein and tends to have higher digestibility.

For your horse to be able to synthesize the proteins, he needs the amino acids be present in the right ratio. If one of the necessary amino acids is present at inadequate levels, this will negatively impact protein synthesis. When you combine the issue of protein quality, protein availability, and the concept of limiting amino acids and the need to have the right amino acids present in the right amounts for protein synthesis, it starts to become clear that all these factors play a role in your horse’s ability to generate anything made up of protein.

If your horse’s lack of topline development is due to dietary protein the goal is to improve the overall protein quality of the ration so that more of the essential amino acids are provided in a digestible format. Skeletal muscle is made up of a broad range of amino acids with the greatest being lysine at about 79 mg/g of muscle tissue, followed by leucine at 77 mg/g and the other branch chain amino acids isoleucine and valine.

It might be tempting to supplement individual amino acids; however, I caution against this because amino acids need to be present in a balanced manner. By giving just one amino acid you run the risk of upsetting this balance. Rather, it’s preferable to provide a source of better quality protein that will supply a range of amino acids.

This is why soybean meal is a common ingredient in horse feed. Soybean meal is the highest quality plant based protein source commonly available as a feed ingredient. Soybean meal provides just more than 60 mg of lysine per gram of protein, which is significantly more than a mid-maturity grass hay with 35 mg of lysine per gram of protein, and even alfalfa with 51 mg of lysine per gram of protein. Correctly offering your horse a commercial feed will often ensure he receives adequate lysine, along with other essential amino acids.

So, what does all this have to do with whey protein?

Whey protein comes from milk and is left after manufacturer’s separate curds from it during cheese making. Once carefully dried to a powder, a highly concentrated source of protein remains. The protein is also very high-quality with more than 60% of the amino acids being essential amino acids, in particular the branch chain amino acids leucine, isoleucine, and valine. With skeletal muscle being made up of a high concentration of these branch amino acids, adequate branch chain amino acid availability is important for muscle repair after exercise. Supplementing horses with whey protein might help support development of lean muscle mass.

However, research in this area is limited and inconclusive. It’s also important to understand that whey protein comes in several different forms. Most commonly available are whey protein concentrate and whey protein isolate. The concentrate is the whey exactly as it was when the curds were removed meaning that it still contains lactose, fat, and various vitamins and minerals. Protein content can vary widely and care needs to be taken as horses over 3 years old are less able to digest lactose, which can lead to digestive distress. The isolate form is a more consistent product and has had much of the fat and lactose removed. As a result, the product is almost pure whey (90% plus) and is considerably more expensive.

Equine whey protein supplements do exist, and I recommend them over those created for people, because those made for people are often for making protein shakes and contain other ingredients and additives that might not be suitable for your horse.

Take-Home Message

If you’re struggling to develop your horse’s topline and feel that there might be a nutrition issue, evaluate your horse’s diet. Consider the sources of protein in the ration and see whether there are easy affordable steps you can take that will improve the overall protein quality and digestibility of the ration. This ultimately might or might not involve supplementing whey protein.

Q. This year was difficult for harvesting hay, so the only hay I could get for my herd of horses has had preservative sprayed on it to prevent mold growth. Should I be concerned about this? Is it safe for them to consume?

A. Harvesting high-quality hay can be challenging for horse owners. To cut and bale premium hay, it must be cut at the right time, dried quickly, and baled at the correct moisture, then moved out of the elements and into storage. Although this sounds straightforward, it can be challenging because it relies heavily on weather conditions. In seasons that have a lot of precipitation, baling adequately dried hay becomes an issue. However, for horse hay, it is crucial that the bales not contain mold and are adequately dried.

Farmers monitor moisture content of forage throughout the harvesting process—when the hay is too wet mold is a concern and those bales could even become a fire hazard, and if the hay is baled too dry, there is significant nutrient loss due to leaf brittleness. Therefore, a happy medium is key.

Farmers might invest in inoculants or preservative sprays to reduce the likelihood of losing a crop because they allow the farmer to bale a hay at slightly higher moisture levels. For example, if the hay is not quite dry enough, but there is rain approaching in the forecast, the farmer might invest in a preservative spray for that field to ensure it can be baled prior to the rainfall. These products are most commonly used in wet and cool climates.

Manufacturers offer two main types of preservatives: bacterial inoculants and organic acids. Bacterial inoculants are typically characterized by the addition of lactic-acid-forming bacteria such as Lactobacillus, Streptococcus, and Bacillus. These organisms compete with mold-forming organisms in order to maintain forage quality. These products allow farmers to bale the hay at 3 to 5 percent higher moisture.

The other common preservative farmers spray on hay is organic acids (e.g., propionic acid). These products produce an acidic environment that is not supportive of mold growth. Again, this allows the hay to be baled slightly wetter so the grower can reduce the amount of time that it is in the field drying with a risk of it being rained on.

Farmers only use these products when absolutely required because they are an investment; however, without them, more hay would be lost in wet years, which would create shortages and cause hay prices to skyrocket.

Regarding horse health, researchers have shown that horses preferentially eat nontreated hay when given the choice. However, it is safe for them to consume treated hay. In one study looking at feeding hay treated with commercial preservatives to yearlings, scientists found there was no difference in feed consumption or weight gain between the treated and untreated hay groups. When we investigate hay treated with propionic acid, keep in mind that the product is buffered; despite it having a very low pH on its own, it is buffered to be closer to neutral (pH of 7) and will not cause harm to the horse when consumed. Additionally, the horse naturally produces propionic acid in the hindgut when hay is fermented.

Although farmers prefer harvesting conditions that allow for the baling of high-quality horse hay without the use of preservatives such as organic acids and bacterial inoculants, these products are a safe and effective way to reduce the risk of mold development in hay. So, from a nutritional standpoint, hay that has been treated with a preservative such as propionic acid is safe for horses.

Do you have a horse nutrition question?

Q: My trainer suggested I add oil to my horse’s diet to help with her weight and coat. Does it matter what type of oil I choose? Are there certain benefits to feeding corn oil versus canola or vegetable oils?

A: Adding fat to a horse’s diet is a common choice when owners want to improve coat quality or weight gain because fatty acids coat the hair shaft, making it reflect light better so hair shines more and becomes more pliable. Fat also provides 2.25 times more calories to the diet than an equal weight of carbohydrates, which enables you to get more calories into the ration without having to greatly increase feed intake. The other benefit of using fat for weight gain is it is widely considered to be a “cooler” source of energy and less likely to make horses excitable than using higher-starch options.

On face value, the answer to the question of does it matter what type of fat/oil is used to improve coat quality or for weight gain, the answer is no. Corn, canola, vegetable, flax oil, etc., will all increase shine and add calories for weight gain. But there are some additional considerations to make because outside of their abilities to improve coat and increase condition, these fats have other effects within your horse’s body.

The composition of these fatty acids varies, with some containing more omega-6 fats while others contain more omega-3 fats. These differences are important to understand because these two types of polyunsaturated fats play key roles in cell membrane structure, inflammation, and other physiological processes.

The fat in a horse’s natural diet of fresh grass tends to be quite high in omega-3 fatty acids. However, these fats are not heat-stable, so much of the omega fat is lost when grass is dried to make hay. Many of the other common equine feed ingredients tend to be higher in omega-6 fats. This is especially true of high-fat ingredients such as rice bran and the vegetable oils used in feeds. This can result in a diet that provides more omega-6 than -3 fatty acids.

Both omega-3 and -6 fats are essential, meaning horses cannot generate them and, thus, must consume them in their diet. Because the level of omega-3 fats tends to be lower when horses do not have access to good-quality pasture, it is ideal to provide supplemental fats that are higher in omega-3 fats when trying to improve coat quality and body condition. This will not only improve coat quality and body condition but also help the horse better regulate inflammatory response.

Although corn oil is relatively cheap, it has no omega-3 fat, so I typically do not utilize it. Other oils often used for weight gain, where you may need to feed up to two cups a day, are soybean oil and canola oil because while these are both high in omega-6 fats, they do contain some omega-3. Better still, and my choices for coat-quality improvement, are flax or camelina oil because these have more omega-3 than -6. Coat quality might improve with as little as 2 fluid ounces a day. Their high cost could make them a more challenging option when larger amounts are needed for weight gain but, if cost is not a constraint, they would be a great choice for weight gain, as well.

Other good oil options are ahiflower oil, which is also high in omega-3 fatty acids including stearidonic acid. Hemp oil also contains stearidonic acid, in addition to an unusual omega-6 fatty acid, gamma-linolenic acid, which behaves like an omega-3.

Feeding any one of these oils will likely have a positive impact on coat quality and, if fed in enough quantity, weight gain, as well. Selecting an oil with higher omega-3 content might also have other added systemic benefits by regulating inflammation, which can help with joint health, respiratory function, immune function, and a number of other conditions.

Q. My horse is starting to shed his winter coat, and I’m wondering whether there is anything I can do nutritionally to speed up the process and that will also ensure a good-quality summer coat?

A. While most of us look forward to the longer days and warmer weather of spring, shedding horses can leave the barn looking like a yak thanks to shedding winter coats. I don’t blame you for wanting it over as quickly as possible!

Some anecdotal reports suggest that feeding flax or black oil sunflower seeds can help horses shed out more quickly. This is likely due to the oil these feeds contain. However, I have found no scientific evidence to support this assertion. The best way to speed up the removal of old coat is rigorous grooming before and after exercise using a rubber curry comb or similar grooming tool. If the weather is warm enough, a bath will often help loosen hair. So will a good roll in a sandy arena.

Don’t be fooled into thinking that blanketing your horse will help them shed faster. Day length is what triggers hair loss, not body temperature.

Fat and Horse Hair Coat Quality

While feeding fat to speed up shedding might be no more than placebo effect, adding more fat to the diet might help improve the new coat’s quality. The hair shaft is coated in cuticle cells that contain a substantial amount of fat that helps retain moisture. These cells should lay flat, and when they’re flat they reflect light beautifully. However, if damaged, moisture is lost from the hair shaft, and the hair becomes dry and no longer reflects light with the same brilliance. Additionally, pores in the skin release sebum, which is an oily substance that coats the hair shaft and helps maintain shine. Diets that don’t provide adequate amounts of fatty acids could result in a dry hair coat that’s more susceptible to damage and a dull appearance.

Take caution before supplementing fat to ensure it is appropriate for the individual horse based on body condition. However, even relatively small amounts of fat should have a positive impact on coat quality. Try to use fat sources that provide essential omega fatty acids especially those that supply greater quantities of omega-3 than omega-6. Flax and camelina oil are good options, and you only need to feed about 2 to 4 ounces per day for an average-sized horse. If feeding flax seed, either whole or ground, feed about 4 to 6 ounces by weight, which is about 1 cup by volume.

Supplementing oil also supports supple, healthy skin and reduces dandruff and flakiness.

Vitamins

Vitamin A is a key nutrient that plays a role in skin health, and while the equine dietary deficiencies are rare, they can occur if you’re feeding older hay. While the precursor to vitamin A, beta-carotene, is abundant in fresh forages, it is lost from hay at a rate of almost 10% per month. Therefore, by late winter/early spring hay might have lost 50% of its beta-carotene, and by the time hay is a year old it’s likely horses will need an additional vitamin A source to meet their basic dietary requirements.

Protein and Amino Acids

The hair shaft is made up mostly of the protein keratin. Diets that provide inadequate protein or that lack essential amino acids could result in reduced hair growth. This, in turn, could slow down shedding. Look at the quality of the forage you’re feeding. Very stemmy hay, the result of cutting plants when they are mature, might need to be supplemented with feeds that provide quality protein, such as soybean meal.

Copper and Zinc’s Role

Ensuring horses’ dietary copper and zinc requirements are met will also help support coat color. Both these minerals impact melanin, the protein in hair that is responsible for pigmentation. If the hair contains inadequate amounts of melanin, it is unable to resist damage from ultraviolet light. This leads to oxidative damage and fading.
Copper is also needed by the enzyme lysyl oxidase, which is necessary for the maintenance of the cross-bridges in collagen within skin. Without adequate copper these cross linkages are weakened and the skin loses structural integrity.

Take-Home Message

A balanced diet with appropriate levels of protein, trace minerals, and vitamins supports healthy skin and coat. For greatest effect you should make sure that all dietary requirements are met before shedding starts. That way the new coat will be fully supported from the very beginning of its growth. Combine this with rigorous grooming sessions and you will have a fabulous summer coat before you know it.

Q: I do not have much space for hay storage on my farm, so I only buy about 10 bales at a time from my local feed store for my pony. They get their hay from various sources so there is little to no consistency. How can I make these constant changes easier on my pony? Should I get my hay tested with each shipment to make sure it is meeting his nutritional requirements?

A: You’re correct in being concerned about the impact of hay variability on your pony’s nutritional well-being. This is an issue I see fairly frequently, even with large boarding facilities, because it can be difficult to source enough hay for the year and have the space to store it.

I have two main concerns with continually changing the forage source in your pony’s diet. First, when you change the fiber type abruptly, it can shock the microbes in the horse’s gastrointestinal tract and cause digestive upset. Second, maintaining a balanced diet that is optimal for your pony can be challenging when you are unaware of the forage’s nutritional content.

Finding a reliable hay supplier is easier said than done; however, if you can travel to pick up the hay, I recommend inquiring with local hay suppliers about purchasing from them regularly. They might be willing to store hay for you, which could increase the consistency of your 10-bale batches.

Testing Hay When Making Horse Hay Changes

If you cannot change hay suppliers or none in your area have a storage system, testing every shipment to make sure it is adequate for your pony is the gold standard. Hay batches often have large variations in nutritional values such as protein, energy, minerals, sugars, and even fiber digestibility. Maintaining your pony on a quality ration balancer that provides a digestible source of vitamins and minerals will reduce the risk of dietary deficiencies from the forage.

Since you are consistently getting new shipments of hay, testing every single batch can become costly. So, despite this being the gold standard practice, it might not be practical. If you cannot test each shipment, at least test a few batches so you can better understand the forage’s variability.

Maintaining Equine GI Health With Hay Changes

As mentioned, one of the main concerns with abrupt fiber changes is the risk of digestive upset. The large population of microbes in the equine gastrointestinal tract gets accustomed and adapts to the day-to-day diet. Therefore, when your pony switches from one hay type to another frequently, it can be challenging to maintain optimal gut health. A simple way to reduce the risk of gastrointestinal upset when switching hay types is to save a couple of bales (even just two or three) to mix with the new batch of hay.

Get your new shipment of hay while you still have a couple of bales remaining from the last batch. Then begin to feed the new forage in combination with the previous batch. You can start with 25% of the new forage and 75% of the previous batch. Ideally, you would maintain this ratio for a couple of days prior to moving to a 50/50 split. From there, you would continue to increase the proportion of new hay in the diet as you decrease the previous batch. In a perfect situation this transition would happen over seven to 14 days, but any type of slower transition is better than an abrupt change. The slow transition will reduce the shock on your pony’s gastrointestinal tract and allow the microbial population time to adapt to the new forage slowly.

Take-Home Message

Sourcing hay can be challenging, especially when storage is limited; however, with careful management, you can reduce the risk of gastrointestinal upset for your pony. Additionally, testing hay when possible and using a quality ration balancer can reduce the risk of nutrient deficiencies in your pony’s diet.

Q. My horse tends to be an easier keeper. I have done some research, and it appears she likely only needs a ration balancer. However, when I go to the feed store, there are many options that appear to be quite different. How can I choose a good ration balancer for my horse?

A. Easy keepers can be challenging to manage because they normally maintain weight on a forage-only diet, which could include hay and/or pasture. However, forage alone does not meet a horse’s vitamin and mineral requirements. For example, if your mare is on a hay-only diet, she will be deficient in vitamin E because it is not heat stable, so a significant amount is lost during hay curing. Additionally, the mineral content of the hay or pasture will largely rely on the soil mineral content. Almost all forages will be deficient in a variety of minerals, but this varies by geographical location. For example, in Ontario, Canada, the soils are generally deficient in selenium.

Therefore, easy keepers or overweight horses will need a ration balancer to meet their daily vitamin and mineral requirements. These are concentrated products that supply the horse with vitamins, minerals, and often protein. They are designed to be fed in small quantities to fill the nutritional gaps in the hay or pasture.

When browsing the feed store for a ration balancer, it is important to know which of the two broad categories of ration balancers your horse needs. There are ration balancer feeds, which supply crude protein in addition to vitamins and minerals and have a slightly larger feeding rate, normally closer to 1-2 kg/day (2.2-4.4 lbs) for the average-sized horse. Alternatively, there are ration balancer supplements that are simply a concentrated source of vitamins and minerals and do not provide significant crude protein. These have a lower feeding rate, normally 100-200g/day (.22-.44 lbs).

When choosing a ration balancer for your horse, consider his individual needs and get a hay (and/or pasture) analysis to determine the nutritional content of your forage. If your hay provides adequate crude protein, you can opt for one of the ration balancers that is simply a concentrated source of vitamins and minerals. However, if your hay is low in protein, a product that includes crude protein might be more ideal for your horse.

In cases where a horse is over conditioned (at a body condition score of 6 or higher), avoid supplying additional energy through the ration balancer. Even though ration balancer feeds are low in digestible energy, they do still contribute more calories than the ration-balancing supplements. Therefore, you might have better results with a ration balancing supplement because it provides less digestible energy while still meeting the horse’s vitamin and mineral requirements.

When buying a ration balancer, look for one that will be optimal for your horse’s individual needs and complements your hay analysis. This is a crucial step for ensuring her nutritional well-being. Frequently, horse owners with the best intentions will feed a performance feed designed to be fed in larger quantities (normally 2+ kg/day) and feed it to their easy keeper at a lower rate. Generally, these owners know their horses are easy keepers and do not need supplemental energy but understand that they still need an additional source of vitamins and minerals. However, this practice can be harmful to your horse because it often leads to vitamin and mineral deficiencies due to the product being fed below the recommended amount.

Overall, when choosing a feed for your easy keeper horse, a ration balancer is likely the best option. Be sure you feed the product at the recommended rate for your horse’s workload and size and always test your hay prior to buying a ration balancer so you can choose a product that adequately fills your horse’s nutritional gaps.

Do you have an equine nutrition question?

Q. My mare had her first foal last week—a beautiful filly! Everything started out very well. The filly nursed, and my mare accepted her without issue. However, now the foal isn’t gaining weight. I’ve heard that sometimes maiden mares don’t create enough milk. Should I supplement her with milk replacer?

A. Congratulations on the birth of your filly! Having a foal can be enchanting, although at the same time quite stressful because so many things can go wrong. If you haven’t done so already, I strongly recommend contacting your equine veterinarian, who might want to assess the foal and rule out any medical cause for the lack of growth.

Sometimes a mare doesn’t produce enough milk to support the foal’s demands. Foals of this age are nursing in the rage of four to six times per hour, and this suckling action helps stimulate milk production. The demands made on the mammary tissue early on help set the stage for how much milk the mare will produce later. Plenty of early suckling is important so the mare can support the foal’s needs as she grows. If the issue is that the foal does not have much drive to nurse, a veterinarian will need to determine the cause.

If given your vet’s “all clear” to supplement with milk replacer, you’ll find several good commercially produced ones designed specifically for foals. Use these and not replacers created for other species such as goats or cattle. Every species has a milk composition slightly different and unique to their needs.

Because of the need for frequent suckling, feed the foal ad lib milk replacer is best, making sure it’s constantly available. This is better than meal feeding her at times that are convenient for you but perhaps not in sync with when the foal wants to nurse. Also, presenting a foal with infrequent large replacer amounts at once risks overdrinking, and milk might end up in the hindgut where it can disrupt microbial population development.

Keep track of how much replacer the foal is consuming each day. A foal born to a 1,000-pound mare might consume up to 4 pounds of replacer a day, at which point you can transition to free feeding a milk-based pellet.

Make sure you’re creating the milk replacer with a dry matter content of 10%. Less than this level of dry matter might leave the foal hungry. From month one to four the foal might consume 1 pound of replacer per 100 pounds of her body weight. The amount of milk the mare is providing will dictate how much the foal needs to consume from the supplemental source, so don’t be alarmed if you see some variation in how much she consumes each day. Keep a journal so you can see the daily consumption level and be able to identify when you can transition to pellets or to record signs indicating she needs veterinary support.

With careful management and supplementation, you should be able to ensure your foal is receiving the correct plane of nutrition to fully meet her genetic potential and develop at an appropriate rate.

Q. Do you have advice for those of us feeding performance horses on tight budgets?

—Glen from Trinidad

A. In my job as an equine nutrition consultant, clients commonly come to me with long lists of products they’re feeding their horses. This is particularly true of my performance horse clients. When added together the cost of these products is significant, sometimes exceeding $5 per day. This kind of budget is not realistic for many who own performance horses. So, your question is a good one.

My advice is to start at the foundation of your horse’s diet and to be fastidious about management. Don’t scrimp on quality forage—it’s the best investment for your feeding dollars. The more you can feed your horse like a horse, the less likely you will incur expensive veterinary bills associated with conditions such as gastric ulcers and colic and the less reliant you will be on concentrate feeds. Make sure the forage is clean and as free of dust as possible, as this will protect airway health. Feed as much forage as you can to honor your horse’s digestive tract anatomy and physiology.

Forage, however, cannot provide everything your horse needs all year round. Even if your forage source is pasture, at some point in the year its quality and abundance will likely drop. Neither pasture nor hay typically provides adequate levels of trace minerals, might not provide adequate vitamins such as vitamin E and, depending on the individual horse and discipline, might not provide adequate calories. This makes a concentrate, commercial feed, or a balancing supplement necessary.

Select a feed you can offer properly per the manufacturer’s directions. If you’re only going to feed a couple of pounds a day, don’t be fooled by the fact the performance or senior feed is significantly cheaper per bag than the ration balancer. Those feeds have daily feeding rates typically in the range of 0.5 to 1 pounds per 100 pounds of body weight. Feeding less than this will leave your horse with key deficiencies that over time might cause health issues and have you reaching for hoof supplements, coat products, and additives that support topline development. Paying more per bag for the ration balancer and feeding it per directions will likely save you money in the long run.

Other essentials include:

1. Fresh, clean water;
2. Salt provided daily, ideally in the feed, with free access to an additional source;
3. Omega-3 fatty acids for horses not grazing pasture for 12 or more hours per day; and
4. Possibly additional vitamin E for those same horses.

Vitamin E supplementation is relatively expensive, and not all horses require it. So, put some money toward getting your horse tested to see whether supplementation is necessary. Horses with deficient or marginal levels of vitamin E in their bodies are at risk of developing conditions such as vitamin E deficiency muscle myopathy and equine motor neurons disease, so this is an investment worth making. Ask your veterinarian to take blood during an already-scheduled visit such as spring or fall vaccinations or during a dental check to save on an additional farm fee.

Whether your horse is going to need supplements depends on his individual needs. Does he have underlying health conditions that need additional support, such as allergies, or need digestive tract support? Do you have the budget remaining to add a joint supplement if you want one? If you decide to add other products, have a clear reason for adding them. Don’t add products just because someone else in your barn is doing it for their horse and seems to be having good results. Their base diet might not be as solid as yours, or their horse’s situation might not be the same as yours. Also, don’t feel bad if you don’t have the budget to add more. Very little research exists on the efficacy of many supplements. If possible, try to use products backed by research so you have some peace of mind that the products do what they say they will.

Also consider investing in a consultation with a qualified equine nutritionist when feeding performance horses on a budget. While it might include an upfront expense, if you explain your situation, they should be able to help guide you toward a diet that meets your horse’s needs as well as your budget. That peace of mind can be priceless.

Q. What recommendations do you have for feeding a horse with equine metabolic syndrome (EMS) a low-carb diet, and is low-carb and sugar-free the same thing?

A. This is a great question and gets at one of my biggest concerns as a nutritionist, which is the belief that all horses with EMS need “low-carb” or even “no-carb” diets.

“What?!” I hear you say, “But I thought EMS horses couldn’t have starch and sugar.” That is a truer statement, although not completely accurate either. Now, I know you are probably completely confused! Let me explain.

Understanding Different Carbohydrates

The horse’s body uses types of carbohydrate, and the key is to understand the difference. There’s starch, or sugars such as glucose, and other sugars that break down into glucose in the small intestine; but there are also complex carbohydrates such as hemicellulose, cellulose, pectins, and lignin. These complex carbohydrates are digested in the hindgut by bacteria and don’t result in elevated insulin levels. For horses relying mainly on forage as a large proportion of their diet, these complex carbohydrates provide the majority of their daily calorie intake.

So to say that a horse needs a “low-carb” or “no-carb” diet is false: All horses need carbs, but EMS horses require a diet lower in starch and simple sugars, often referred to as non-structural carbohydrates (NSC).

You might be asking, “Is this sugar-free then?” and the answer is probably not. Most hays, even with low NSC, still contain a small percentage of simple sugars, and many have some level of more complex sugars, called fructans, as well. The goal is to reduce the total intake of starch and simple sugars to below about 10-12%. Research shows keeping NSC at or below these low levels helps maintain more stable insulin levels, which is a key component of managing insulin-resistant EMS horses.

How much each horse can handle is an individual thing. Horses with EMS that are in good weight, currently sound, and able to work might better handle slightly more NSC in their diet than laminitic and/or obese horses.

Finding the Right Forage

Because the foundation of any horse’s diet should consist of forage (i.e., hay, legumes, beet pulp, etc.), it’s important for the EMS horse to consume forage that has a low NSC level. The only way to know for sure is to test the hay at a lab, which is a relatively inexpensive (about $30 depending on the lab). Tests performed need to at least determine the forage’s carbohydrate profile; but it’s also worth having the forage’s mineral and protein levels checked as well. Testing requires taking a proper sample ideally using a hay corer to sample at least 15 bales. If hay changes frequently then testing might not be worthwhile as each batch will be different.

If feeding untested hay to a horse requiring a low-carb diet, you should soak the hay to wash out some of its water-soluble sugars (soak they for 30-60 minutes if using cold water—any longer than that and other nutrients might be lost). Note, however, that while soaking hay will lower its sugar content, it might not lower it to the ideal NSC range of 10-12% NSCs.

Typically, nutritionists and veterinarians recommend grass hays for horses with EMS, even though alfalfa (a legume) has a low glycemic index, which means it doesn’t tend to cause blood-glucose and insulin spikes. Alfalfa is, however, higher in calories than grass hay, meaning easy-keeping EMS horses would require less alfalfa than other forages. Less daily forage intake can have a negative effect on gastrointestinal health and cause well as boredom, so I typically do not recommend alfalfa to horses with EMS.

Instead, mature grass hay is a good option. As grasses mature they develop a greater proportion of complex structural carbohydrates relative to NSC. They’re also lower calorie than less mature grass hays, which means you can feed more before you reach the horse’s maximum calorie intake. For easy keepers who are often having their intakes whittled down to the bare minimum this can be a very good thing.

Make Sure EMS Horses Get the Nutrients They Need

Often, my clients with EMS horses reduce the amount of forage they provide to avoid obesity in their animals. Unfortunately, this can result in diets deficient in trace mineral and vitamins. It’s important, therefore, to supplement for these missing pieces. For horses that can tolerate extra calories, a high-protein ration balancer is a nice addition. These feeds have a small 1- to 2-pound serving per day and insure good quality protein in the diet and provide necessary trace minerals and vitamins. For horses that shouldn’t consume extra calories, equine nutrition companies have formulated heavily fortified supplements fed in 3- to 4-ounce servings. These supplements don’t offer much protein but typically have added essential amino acids.

Omega-3, Magnesium, and Psyllium Supplementation

Horses with EMS might also benefit from omega-3 fatty acids and magnesium supplementation. Some research suggesting that, at least in the short term, omega-3 fatty acids could help improve insulin sensitivity. Similarly, daily psyllium supplementation might also help; however if you feed psyllium daily, it might lose its sand-clearing effectiveness.

Whether magnesium will EMS horses depends on whether the diet you’re feeding is already providing enough magnesium or not. If it is, then supplementing more will probably have little effect. Some magnesium supplements have added chromium, which might or might not be beneficial but is unlikely to be detrimental. However, too much magnesium can result in loose manure, so don’t get carried away.

Take-Home Message

Feeding EMS horses a balanced, low-NSC diet is key to their successful management. Insuring that all nutrient needs are met and means all the horse’s metabolic pathways have what they need to efficiently and optimally function. This will give your horse the best chance of staying healthy, in good weight, and will hopefully help avoid laminitic episodes.

Q. My easy-keeper just got put on 30 days of stall rest with 15 minutes of hand walking twice a day due to a possible soft-tissue injury. He’s the kind of horse that requires regular exercise to stay fit and trim and eats on the low end of what’s recommended for his size and activity level. His diet prior to stall rest included orchard grass hay and a ration balancer. He’s bored in his stall and hoovering down his hay and feed. I’m concerned about him gaining weight because that could add stress to his injury. How can I keep him from gaining weight while on rest while also keeping him entertained?

—Nicole, via e-mail

A. Confinement and rehabilitating easy keepers can be a real challenge. You’re right in wanting to minimize weight gain in order to control stress on the soft-tissue injury as well as wanting to minimize the risk of boredom while he’s out of work.

Typically, when calories need to be cut, grain (concentrate feeds) should be the first thing to go. So, it’s tempting to remove the ration balancer. However, this is needed to ensure his diet remains balanced and is providing enough essential nutrients, such as copper, zinc, and vitamin E, which a hay-based diet might lack.

Ensuring adequate copper is important because it’s needed for collagen formation, and that’s the foundation of the soft tissue you want to heal. Therefore, I would avoid reducing his ration balancer amount unless absolutely necessary. Should it become necessary to reduce the ration balancer you could switch to a ration balancing supplement rather than a feed, which will have fewer calories.

Nutrient Intake Matters for Healing

Calorie reduction is going to be from reducing the amount of hay being fed, which I dislike doing. Plus, it sounds as though you’re already feeding the low end. I’d become diligent about weighing the hay you’re feeding, so no extra ounces sneak into his feeder.

Calculate your horse’s body weight, too, and make sure that you maintain a hay intake of 1.5% of estimated body weight. You can go as low as 1% of body weight, but I am always loathed to do that and would not suggest it unless absolutely necessary. I’ve seen horses become destructive and begin stereotypic behavior such as wood chewing and eating bedding at such low intakes. Gastric ulcers and other gastrointestinal issues are also a greater risk on such low intakes.

Slow Down Feed Intake

The trick is therefore to figure out how to make the reduced ration take a long time to eat in order to keep the brain and gastrointestinal tract busy. This is where the numerous slow feeders on the market are very beneficial.

Using small-hole, slow-feed haynets are an excellent way to slow hay intake. There are numerous manufacturers of these nets and they come with holes in an assortment of sizes. You can start with a moderate size hole and get increasingly smaller holes if needed to slow down intake. Dividing the day’s total hay into as may small meals as you can manage will also help. However, this can be unrealistic depending on your lifestyle. For this reason, I like automatic feeders that can be used to feed hay pellets. You could also use one to dispense the ration balancer.

Take-Home Message

Maintaining an easy keeper on stall rest can be challenging. Feeding too little can risk your horse not getting the nutrition he needs and cause stomach issues. Try a vitamin and mineral supplement instead of a ration balancer feed to reduce calorie intake, and use slow feeders to help meals last longer and stave of boredom.

Q: I have a 28-year-old gelding who suffered an impaction colic last week. We’re not really sure why it happened, because nothing has changed in how he is managed. What can I do to help prevent it from happening again?

A: Colic is scary to witness, and not knowing the cause can be very stressful. Of course we all want to make sure it doesn’t happen again. Assuming there’s no physical cause for impaction, such as a tumor, which can occur in older horses, common causes include dehydration and poorly digested feed. Therefore, avoiding dehydration and improving digestion are key.

Salt and Hydration

Ensuring your horse is consuming enough water is necessary for avoiding dehydration. Sodium intake each day helps stimulate water consumption, so make sure your horse gets enough salt each day. Many owners rely on salt blocks to provide their horses with a sodium source, but few horses adequately utilize salt blocks.

An average 1,100-pound horse must consume about an ounce of sodium chloride a day to meet maintenance sodium requirements. This would be equivalent to consuming 2 pounds of salt in block form each month. Few horses achieve this intake from blocks. Therefore, I like to feed horses an ounce of salt (which is 2 tablespoons) each day and then provide them access to a plain white salt block, as well. If the weather is hotter, then you can give additional salt or an electrolyte supplement. If your horse does not like the taste of salt, then you can use an electrolyte instead, because sometimes electrolytes are more palatable than straight salt.

Salt consumption should stimulate thirst and encourage your horse to drink. Make sure water is easily accessible. If older horses have joint pain they might be less willing to walk distances to get to water, so consider having several water sources available. When feeding hay, you might find your horse drinks more if water is near his hay.

Soaking Hay

That said, soaking hay is an effective management strategy for horses prone to impaction colic. First, it increases water intake without the need for drinking more water, and secondly it softens the hay and makes it easier to chew. Keep in mind that horses fed soaked hay might not consume as much water from other sources, such as buckets or troughs, so it might initially appear that your horse is consuming less water.

Even if senior horses have healthy teeth, they might not have as much strength in their jaws to grind and chew hay as when they were younger. Inadequately chewed hay creates a greater impaction risk. Soaking hay to make it softer can be beneficial. Feeding softer, less stemmy hays might also help, because they tend to be more easily digestible. Senior horses that can graze pasture grass safely might have a reduced impaction risk when grazing, because fresh grass contains more water and is softer and easier to chew than hay.

Pellets Instead of Hay

For some horses, feeding hay pellets might be a better option than long-stem hay. Once chewed, pellets have very small particle sizes, which reduces impaction colic risk. If desired, you can feed pellets soaked. In fact, you can prepare any textured or pelleted feed as a mash or soup as a way of increasing water consumption.

Hindgut Health

In addition to making sure your horse consumes enough water and chews his forage properly, supporting forage digestion might be beneficial. Research shows supplemental live yeast can help improve organic matter utilization in the hindgut. This improvement in forage fermentation might help reduce the risk of hindgut impaction.

Exercise

Finally, make sure your horse is getting adequate exercise, as movement aids digestion. Senior horses tend to move less due to joint pain or because they have been retired from riding. Have your veterinarian look over your horse and provide him with support for any joint discomfort. If your horse isn’t turned out, consider at least hand-walking or longing him each day.

Take-Home Message

By implementing some of these recommendations and practicing overall careful management you can potentially limit your older horse’s risk of a repeat impaction colic episode.

Q. I live in an area in which winter is extremely cold and snowy. Keeping unfrozen water available for my horses is a challenge, especially in their pasture. I have noticed my horses eating snow when they’re turned out, even though water is available. Do I need to give them water, or can they get enough water from the snow during turnout?

—Via e-mail

A. As a rule, horses need continuous or frequent access to clean water at all times. This certainly poses a challenge when temperatures fall below freezing. Tactics such as floating tennis balls in troughs will prevent water from freezing when temperatures are at or very slightly below freezing. However, when temperatures fall well below freezing, as we have seen across much of the United States in the past week, these tactics don’t work.

Horses kept on snowy pasture will lick and eat snow, and this certainly provides a source of water. The question is, however, is it enough to meet the horse’s needs and prevent dehydration?

What One Study Found

There appears to be limited research on this topic, but a group of Norwegian researchers studied a group of Icelandic horses on pasture for more than a year to observe how extreme weather conditions affected the horses’ shelter use. As part of that study, they drew blood at intervals throughout the year, which allowed them to compare hydration parameters.

Due to some unexpected extreme weather conditions, the horse’s only natural water source froze for nine days during the second December of the trial. There was approximately 20 centimeters (nearly 8 inches) of snow on the ground during this period of time. The researchers drew blood on the horses at the end of the nine-day period to osmotic concentration to samples collected in other seasons, including samples taken the previous December. An increase in the osmotic pressure of the fluid surrounding cells stimulates receptors in the brain, which in turn promote the excretion of a hormone called vasopressin. Vasopressin is an antidiuretic hormone that reduces the amount of fluid lost in urine to help maintain bodily fluid levels. Additionally, studies have shown thirst in other species results after a 3% increase in osmotic concentration occurs.

The horses showed no physical change in appearance after relying on snow as their sole water source for nine days, and the researchers didn’t observe any change in the herd’s feed intake or feeding behavior—their feeders were filled with grass silage at the same frequency whether the horses had water available or not. A veterinarian examined the horses and found no clinical signs of ill health, including response to skin turgor testing (elasticity when pulled, or the “pinch test,” an indicator of hydration).

Also at the end of the nine-day period, the researchers gave the horses access to water from their commonly used drinking bowls and reported that they showed very little interest in drinking—some did not drink, and those that did only drank for a few seconds.

Bloodwork showed no significant differences in osmotic concentration between the samples taken after nine days without free water and the one taken the previous December, when the horses had access to water. With the lack of free access to water in this case, the researchers expected an increase in osmotic concentration; however that did not appear to occur.

The horses appeared unaffected by having only access to snow as a water source for the nine-day period.

Horses Still Need Access to Water

The researchers concluded that horses eating grass silage and adapted to consuming snow can manage for several days with snow as a substitute for liquid water. However, there are some important points to understand about these conclusions when applying them to horses kept in similar, but not identical, conditions.

First, the grass silage had a dry matter content of more than 30%, while a typical grass hay would likely have a dry matter content of more than 80%. Silage is typically quite moist and, therefore, provides greater source of moisture to the horse than dry hay. And, people with experience feeding silage note that in more typical conditions, horses still consume 15 to 30 liters (roughly 4 to 8 gallons) of water a day. This would suggest that consuming silage alone is not an adequate source of moisture, and the snow must have provided a fairly significant hydration source. Also, the amount of water needed from snow would likely be less for silage-fed horses than hay-fed ones, and it’s possible that snow alone might not be able to meet the latter group’s water needs.

Another important consideration: Horses in this study were used to living in snowy conditions and eating snow, and the Icelandic breed is hardy and developed in a country that has cold winters. A horse that’s not as well-adapted to such conditions and isn’t accustomed to eating snow might not consume enough to fully meet its water requirement.

Finally, snow consumed by horses could be contaminated with grit and dirt that might contribute to sand colic.

Take-Home Message

The recommendation remains to always provide horses with a source of fresh, clean, and unfrozen water. Still, this research suggests that it might be possible, in severe conditions, for certain horses adapted to winter conditions to rely on snow as a water source.

Q. My horse is 34 years old and has very few teeth left. I currently feed him senior feed, which I make into a very soft mash, in addition to his chopped hay, but he does not maintain his weight well during the winter. Can I replace some of his senior feed with wet beet pulp?

A. How wonderful that your horse has reached the age of 34 and that you are working to keep him happy and healthy! It is better to make dietary changes before the horse starts losing weight, because it can be difficult to reverse the process during winter, when horses use so many calories to thermoregulate and maintain core body temperature.

You do, however, have a few options to help your horse maintain body weight. The first would be to increase the amount of senior feed you’re giving him. Senior feeds are often designed as complete feeds, so they can make up the entire diet. If you don’t see this mentioned on the label, check with the manufacturer to see if your senior feed is a complete feed. Giving a few additional pounds of the feed he’s already on might be the easiest option.

You could also add beet pulp to his diet to help him maintain his weight during the winter. Beet pulp is a great addition because it contains a nice complement of different types of carbohydrates: nonstructural, which horses digest rapidly, and structural, which they digest slower. This gives your horse an immediate source of calories and provides heat during the digestion/fermentation of the nonstructural carbohydrates. Wet or soaked beet pulp can also help your horse stay hydrated in winter, when his water intake might decrease. You might just add some beet pulp to his current ration of senior feed, rather than replacing it. Make sure the diet is still balanced once you make this change—in other words, ensure it provides all the nutrients your horse needs. Protein to maintain muscle mass and a calcium-to-phosphorus ratio of 2:1 to maintain the skeletal system are especially important.

I would still offer the chopped hay because forages help keep the digestive tract healthy and functioning well. When horses consume hay, their bodies digest/ferment it primarily in the hindgut. Similar to beet pulp, this fermentation produces heat internally, which can help keep your horse warm in the winter, and he will have to use fewer calories/energy stores to maintain body temperature.

Monitor the weather throughout the winter and early spring so you can be prepared for changes. Increasing forage intake when you expect colder-than-normal temperatures or snow and cold rain can help your horse stay warm. Keeping your horse dry and out of excessive wind will also help. Maintaining body temperature is more difficult in winter and one reason so many horses lose weight.

Keep an eye on water intake and your horse’s hydration status, because some horses will drink less due to it either being too cold or unavailable (frozen). Low water intake can lead to improper digestion and impaction colic. Be sure water is always available and at a temperature your horse will drink. Frozen water buckets can make it difficult for your horse to get enough water, because not all horses are willing to break ice on the bucket or trough. Consider heated water buckets or a submersible water heater to help keep water at a comfortable drinking temperature, but make sure they are grounded properly and are not emitting a current into the water. 

Make it a habit to routinely monitor your horse’s weight and body condition throughout the fall, winter, and early spring, so when you notice changes, you can adjust the diet quickly.

Q: Is it okay to feed my horse peppermints and sugar cubes? I’m concerned about the amount of sugar they contain. If it is okay, how many is too many?

A: Simple sugars, such as the sucrose found in peppermints and sugar cubes, are absorbed by the horse’s small intestine as glucose and fructose. Glucose causes release of insulin to facilitate the entry of glucose in to cells. Fructose (not to be confused with fructans) is metabolized differently. Only metabolized in the liver, fructose is more lipogenic than glucose, meaning that it’s more likely to lead to production of fat.

Most concern about sugar and starch intake has stemmed from our increasing knowledge about insulin resistance (IR), laminitis, polysaccharide storage myopathies (PSSM), and equine gastric ulcer syndrome (EGUS). Horses with IR release more insulin than is normal in order to remove glucose from their blood stream. As a result, while circulating glucose tends to be normal, circulating insulin is elevated. High circulating insulin creates an increased risk for developing laminitis. Horses with PSSM store glycogen (the storage form of glucose) abnormally in their muscle tissue, and diets high in starch and sugar cause increased production of volatile fatty acids in the gastric stomach causing a more acidic environment and a greater likelihood of a horse developing EGUS

I think it’s important to put the questions of sugar in treats in perspective of a horse’s typical daily non-structural carbohydrate consumption. If we assume a 1,200-pound horse eating 2% of body weight as dry matter from hay a day, and that the hay contains 10% moisture and 10 % nonstructural carbohydrate (NSC) on a dry-matter basis (a value often used as the recommended upper NSC level for horses with metabolic issues, such as IR and PSSM), this horse is consuming 1,090 grams of NSC (starch and simple sugars) per day.

A pure sugar cube weighing about 4 grams is 100% sucrose. The popular round, red-and-white peppermint candies have a human serving size of three pieces (about 15 grams) and of that between 8 and 10 grams are sugar. Traditional peppermint candy canes are heavier at 18 grams and provide about 12 to 14 grams of sugar. You can see that in the context of the above horse’s daily diet these are tiny intakes of sugar. However, there are some important considerations.

When feeding a horse hay, you’re also feeding it proteins and minerals that help buffer stomach acid. Additionally, hay’s fiber component impacts the rate at which the NSC reaches the small intestine and is absorbed. The sugar in sugar cubes dissolves quickly and will move with the liquid fraction of the digesta, which moves more rapidly than larger fibrous particles. This means that that the sugar will likely be absorbed relatively soon after it is fed. This makes it potentially more likely to cause a spike in blood glucose than the NSC contained within hay.

Feeding a healthy horse three or four sugar cubes is unlikely to cause a significant glucose spike; however, for a horse with uncontrolled IR, PSSM, or a laminitis history, feeding sugar cubes isn’t a risk worth taking. Skip the sugary treats, too, if your horse is overweight, especially if he has a cresty neck. After all, every calorie counts and calories from treats mean feeding fewer calories from “real” food. Human research shows that tissues in insulin resistant people are more sensitive to insulin after exercise. This may or may not be the case in horses, but if it is, then your horse might be better able to handle the sugar in these treats when they are given shortly after work.

For the otherwise healthy horse, consuming a candy cane or a few peppermint candies is unlikely to have any major impact.

Q. My horse was diagnosed with equine metabolic syndrome (EMS) and the hay I have is higher than 10% in nonstructural carbohydrates (the recommended, safe level for EMS horses)—but only slightly. Can you explain what this value means and how ethanol-soluble carbohydrates (ESC) and starch play a part in the equation? Could my forage be safe for my EMS horse after all­­?

A. This is a great question because understanding your metabolic horse’s sugar intake is a key step in developing a supportive nutrition program. The important thing to understand is the difference between ethanol-soluble carbohydrates (ESC), water-soluble carbohydrates (WSC), and nonstructural carbohydrates (NSC).

Ethanol-soluble carbohydrates are essentially simple sugars and have a direct impact on blood glucose levels. Water-soluble carbohydrates include both the simple sugars and fructans (the primary storage carbohydrate in cool-season grasses); however, when calculating NSCs you can add WSC and starch (the primary storage carbohydrate in legumes and warm-season grasses) values together but recognize that fructans do not play a direct role in blood glucose and insulin levels.

Microbes in the horse’s hindgut ferment fructans. This results in lactic acid production and, when a buildup of lactic acid occurs, the pH of the hindgut environment drops. This change in the environment negatively impacts the microbes, and many might die off. When this happens endotoxins are released into the bloodstream, which can cause laminitis. Therefore, fructans can play a role in laminitis but, if you are most concerned about blood insulin levels, it might be acceptable to exclude fructans from the calculation.

The most up-to-date recommendations suggest calculating hydrolyzable carbohydrates (HC), which is the calculation of ESC plus starch. The fructans are not included because they are not directly related to a high glycemic response. That being said, if you have a horse that is struggling with laminitis, it is best to avoid any potential triggers, including fructans.

Likely the most important consideration is that the 10% NSC recommendation is simply a guideline. Just because a hay is low in ESC and starch does not mean your horse will not have issues with it. For example, some metabolic horses might be on a diet that is 14% HC and never have issues, whereas others might need less than 8%. It is truly individual; keep this in mind when you are designing a feeding and management program for your metabolic horse.

When choosing a hay for this horse, you will want to test the hay to ensure that the ESC + starch is less than 10% on a dry matter basis. Normally these horses will do quite well on a grass or grass mix hay that is mature. If the hay you can source is too high in sugar content, soaking can be an option. However, the climate you are in can limit this as a practical year-round option if temperatures are freezing. When soaking hay, it should be completely submerged in water for 60 minutes if in cold water, or 30 minutes in warm water.

The other key consideration is the amount of hay you should be feeding your horse. Free-choice hay is fantastic, unless it results in obesity. Many metabolic horses tend to be overweight so reducing their hay intake and using slow feeding tactics might be necessary. If your horse is sound, increasing movement is another positive way to promote weight loss.

When a horse is overweight and needs to lose weight, equine nutritionists recommended feeding hay at a rate of 1.5% of their body weight. It is not recommended to reduce their hay intake below this amount. For a 500 kg (1,100lb) horse this is about 7.5 kg (16.5 lbs). If the horse is not overweight, feeding at 2% of their bodyweight is the usual recommendation. However, remember that each horse is individual so if you are unsure, check with your veterinarian or nutritionist.

Overall, understanding the sugar content of your metabolic horse’s diet is a crucial part of management, but remember it is simply a guideline. When dealing with a history of laminitis, always follow your veterinarian’s recommendations and consult a qualified equine nutritionist if you are looking for help with an optimal diet plan.

Do you have an equine nutrition question?

Q: I have two ponies with metabolic problems. I’ve been researching the best ways to feed them, but there are several terms I don’t understand. I see terms such as nonstructural carbohydrates, hydrolysable carbohydrates, and so many more, but I can’t make sense of them. Help!

A: Carbohydrates serve as the primary energy source for horses and can be divided into two broad categories: structural and nonstructural. The equine gastrointestinal tract is designed to handle large amounts of structural carbohydrates, which are abundant in forages. Sugars are nonstructural carbohydrates (NSCs) and a key concern for owners managing horses with metabolic or digestive disorders.

An important factor when classifying carbohydrates is where in the gastrointestinal tract they are digested. For example, those digested and absorbed in the small intestine provide more energy to the horse than those digested by microbial action in the hindgut, which includes the cecum and large colon (or large intestine). When enzymes break down carbohydrates in the small intestine, the resulting sugars are absorbed into the bloodstream as glucose, stimulating an insulin response.

Common Equine Nutrition Terms

You’ll likely come across a variety of terms when reading about equine nutrition, especially if you research how to manage your metabolic horse’s diet. You’ll likely see the common term NSC, but you might also read about starch, fructans, water-soluble carbohydrates (WSCs), ethanol-soluble carbohydrates (ESCs), and hydrolysable carbohydrates (HCs).

Feed manufacturers use these terms in a variety of places, from educational articles to hay analyses and feed labels, so it’s valuable to understand what they mean and how to navigate the terminology. The authors of Nutrient Requirements of Horses, 2007, propose a three-prong partitioning system for carbohydrates in the equine diet: slowly fermentable carbohydrates, rapidly fermentable carbohydrates, and hydrolysable carbohydrates.

1. Slowly Fermentable Carbohydrates: The horse’s gastrointestinal tract has evolved to consume large amounts of slowly fermentable carbohydrates. These complex molecules are not digested by enzymes in the horse’s foregut (stomach and small intestine). Instead, they are fermented in the hindgut to produce volatile fatty acids (VFAs) as an energy source. Examples include cellulose and hemicellulose.

2. Rapidly Fermentable Carbohydrates: These carbohydrates cannot be broken down by enzymes in the horse’s foregut but take less time to be fermented in the hindgut than fiber, for example. The fermentation process produces both VFAs and lactic acid. Examples include fructans, oligosaccharides, and resistant starch.

3. Hydrolysable Carbohydrates (HCs): Hydrolyzable carbohydrates are made up of the simple sugars and starch that can be digested by enzymes in the horse’s foregut. The body absorbs these molecules as glucose, and they have a direct impact on blood insulin levels. Examples include glucose, sucrose, and fructose. The calculation for HC is ESC + starch.

4. Ethanol-soluble carbohydrates (ESCs): ESCs are the simple sugars (mono- and disaccharides) digested by enzymes in the foregut. Glucose is an example of an ESC.

5. Nonstructural Carbohydrates (NSCs): Nonstructural carbohydrates are calculated values composed of both the hydrolysable and rapidly fermentable carbohydrates. The calculation is WSC + starch.

6. Water-soluble carbohydrates (WSCs): Water-soluble carbohydrates are a subsection of NSC and include the simple sugars and fructans.

7. Fructans: Fructans are a type of nonstructural, or rapidly fermentable carbohydrates. They cannot be digested by enzymes in the foregut and, therefore, pass on to ferment in the horse’s hindgut.

Take-Home Message

Although carbohydrates in horses’ diets occasionally get a bad reputation, they serve as the primary energy source for horses and are critical to balanced nutrition. Understanding the different carbohydrate terms can help you ensure that your horses are on a safe nutrition program if they are sensitive to excess starch and sugar.

Growing up in the United Kingdom, late summer and early fall were the times when  the hay barn was filled with enough of that year’s harvest to get us through the winter. Once we had filled the barn, we always had a sense of relief and a feeling that we were ready for whatever winter might bring. It was a time of year to look ahead to winter and make necessary preparations. Now I live in Arizona. Some would hardly consider our state as having a “winter,” but we do drop 60-plus degrees Fahrenheit from summer temperatures, so some preparation is still necessary.

In no particular order, here are a few of the things I have been thinking about that you might want to put on your getting-ready-for-winter checklist.

Assess your horse’s condition.

Too fat or too thin? If too fat, then winter can be your friend. Cooler temperatures can result in weight loss, even without reducing feed intake, which is ideal. Skip that blanket, and let your overweight horse burn some calories producing heat to stay warm. If your horse is on the thin side, then try to put pounds on him before winter sets in and weight gain becomes harder. Assess the possible cause of weight loss. It’s always a sign that your horse’s calorie level is inadequate. You might already be feeding a lot, but those calories aren’t getting to their destination. Ask yourself why, and what else is going on. Have your veterinarian assess the horse to rule out dental issues, internal parasites, and pain, which can all cause weight loss. Is the horse being bullied in pasture and kept away from hay? Maybe he’s a hard-keeper and needs more than just hay? Perhaps he needs digestive tract support to facilitate hindgut fermentation and better use the forage in his diet? Consider working with a qualified equine nutritionist who can suggest ways to best support weight gain.

Condition tack and send in for repair.

If you ride more in the summer than winter and will be letting horses down, now is a good time to send in tack for repairs, such as stirrup leather restitching or saddle billet replacement. If you won’t be using an item for a few months, condition it and put it in storage. If you ride more in the winter, take equipment out of storage and prepare them for use.

Service clippers and blades.

If you will be body-clipping this winter (and you didn’t do this at the end of last winter), send your clippers to be serviced and blades sharpened. It will make for a much more pleasant job, and your horse will appreciate clippers that run cool and blades that cut well.

Check blanket fit/search for preseason sales.

If you are clipping, you will likely be blanketing. Depending on the weather, you might need to blanket even if your horse is unclipped. Keep in mind that many of us overblanket. Educate yourself on good blanket selection for your climate. Make sure existing blankets still fit, as sometimes blanket fit changes as horses gain or lose weight. If you need something new, now is a great time to hit preseason sales. Mend any blankets you didn’t get mended last year, and consider buying spare leg straps and a rip repair kit so you can keep your blankets functioning through the season. If you live in a dry climate, have static guard (available from the laundry aisle) on hand.

Be weather ready.

If you live in a wet climate, prepare now for mud. If your horses get turned out, what area will you make your sacrifice area? Consider placing fine gravel in heavy-traffic areas such as gateways and around water troughs. Check with local clean water agencies and university extension offices, as they often have excellent resources and help that is appropriate for your area. If you live in a region that gest snow and ice, stock up on vegetable shortening to pack in to hooves to prevent ice balls from forming during turnout. Keep it somewhere where it will be warm enough to scoop out of the container!

Check lights.

Discovering in the dark on a cold night that a bulb has burned out is frustrating. Many of us do not use our barn lights in the summer, so now is a good time to make sure all circuits are working.

Assess pasture condition.

Do your pastures need to be reseeded, harrowed, rolled, or mowed before being shut down for the winter? Now is the time to get out and do those tasks while you can still get machinery into pastures without damaging them.

Buy an electric kettle for your tack room.

Great for defrosting frozen facets and making hot cocoa, every tack room should have one! Unplug it when not in use.

Check trough heaters and buckets.

For those in colder climates where frozen buckets and troughs are issues, check existing bucket and trough heaters to make sure they work. Consider purchasing if you do not have these already, or look online for ways to insulate water troughs and keep them from freezing without the need for electricity. If using electric heaters, be certain your horse will not get shocked while drinking.

Lag pipes.

Nobody enjoys frozen or, worse, broken pipes. Insulate them as well as possible. Have a plan for what you will do if your water supply does freeze. How will you get water to your horses?

Feed salt.

If you do not do so already, add 1 tablespoon of salt per 500 pounds of body weight to your horse’s ration, and provide an additional salt source. As the weather fluctuates through fall into winter, many horses do not drink as much. Add to that the transition from pasture to dry hay and reduced movement once stalled, and it becomes obvious why incidences of colic increase as we go into winter. Keeping your horses drinking is a great insurance against impaction colic, and salt will help encourage them to drink.

Whether we like it or not—and in Arizona I admit we like it—winter is coming. Take the time now to be prepared.

Q: My senior horse is missing most of his teeth and cannot eat hay like he used to. How can I make sure he has enough fiber in his diet now that he eats pellets? Will he still be able to get all the essential nutrients through the pellets?

A: Horses’ teeth are interesting because they erupt over their lifetime similar to lead in a mechanical pencil. The tooth gets worn down but more erupts until eventually there is no more lead in the pencil. Senior horses with few or no teeth find hay-based diets challenging because they do not have the ability to grind the longer stemmed pieces of hay into the small particles they would have created when their teeth were more functional.

An inability to chew forage properly has multiple implications. Obviously, if hay is not being ground down into small enough pieces, the horse is at increased risk of impaction colic. Larger poorly chewed hay pieces might also irritate the intestinal lining, leading to inflammation in the gut lining and colitis (inflammation of the colon). Finally, larger pieces of hay are not digested as well due to their relatively smaller surface area, giving digestive enzymes and hindgut bacteria less room to work.

Substituting long-stem hay with hay pellets is one solution for senior horses. The hay has been chopped into tiny pieces and then reformed into a pellet, forcing it through a piece of machinery called a die under heat and pressure. For horses with no teeth, it is generally recommended that these pellets be soaked prior to feeding so that they disintegrate back into the tiny chopped pieces, reducing the risk of choke.

The particle size of chopped hay is far smaller than that of properly chewed hay when the horse has functional teeth. This greatly increases the relative surface area and often results in greater feed utilization due to improved digestion. This can also be very helpful if your horse struggles to maintain weight.

Fiber is a collective term for several carbohydrate fractions found in various feeds. Some of these carbohydrates, such as hemicellulose, are quite readily fermented and broken down by the hindgut microorganisms. Other fiber fractions, such as lignin, are not. If you take a bale of hay and convert it into hay pellets, the fiber content is the same because fiber is something that exists at a cellular level. The fiber in hay pellets might in fact be more available to the horse due to the possibility of better microbial attachment and fermentation than when it is in its original hay form.

The greater issue is the fiber’s form. Horses typically eat hay pellets faster than hay, which might lead to boredom. They also result in less gut fill and might stimulate the gut lining less. In ruminant animals such as cows, “scratch factor,” as it is known, is important for maintaining a healthy rumen lining. Our knowledge of the importance of long-stem forage on the physical health of the equine hindgut is less well known. However, pellets will not result in the same quality of fiber mat being made in the stomach, and the reduced chew time means less saliva production and less ability to buffer stomach acid. Therefore, horses fed exclusively pellets might be at greater risk of developing gastric ulcers, so feeding the daily pellet quota in as many small meals as possible throughout the day important.

Feeding special needs horses is often an exercise in risk management. While it might be advantageous to feed some amount of the forage as long-stem hay for gut health purposes, if your horse’s teeth are at a stage that this could result in choke or impaction colic, then it’s something to avoid. You might need to accept the possibility that your horse’s chosen diet could increase his risk of other health concerns.

As far as providing all essential nutrients, it is very unlikely that a straight hay pellet will achieve this, which is also true of long-stem hay. Forages are typically too low in trace minerals such as copper and zinc, vitamins such as vitamin E, and sometimes quality protein to meet the horse’s needs.

If your horse can be maintained solely on hay pellets, then adding a quality ration balancer is recommended. However, if weight maintenance is a struggle when feeding only hay pellets, a properly fortified complete senior feed might be a better solution. Complete senior feeds are typically formulated with ingredients that are more readily digestible and might contain more fat to help maintain condition.

Q: My new mare’s previous owners said she’s a hard keeper during the winter and recommended adding fat to her diet in the colder months to help maintain her weight. But when I looked online, I found many recommendations about different supplements, oils, and grains, and I’m not sure where to start. What’s the best way to add fat to a horse’s diet, and which products are most effective?

A: When adding fat to the diet for weight gain it is important to ensure the diet remains well-balanced. Therefore, the most nutritionally complete way to add a fat source to your horse’s diet is to use a higher fat fortified commercial feed fed at the recommended daily intake level. These feeds often having 10-12% crude fat, not only adding fat to the diet but also essential vitamins and minerals, protein, and other nutrients.

Oils are a great way to add fat calories to a ration but provide only calories, not other nutrients. Depending on the rest of the horse’s diet, it is possible when supplementing oil to provide your horse with adequate calories but create a diet that is deficient in other key nutrients, especially minerals and vitamins. This could hinder weight gain, as these essential nutrients are necessary for proper functioning of metabolic pathways. Another benefit of using fortified high-fat feeds is that they tend to contain sources of highly digestible fiber, such as beet pulp and almond hulls, so you have the benefit of adding cool calories from two different sources: fat and fiber.

Rice bran is a popular choice due to a fat content of more than 20% on a dry matter basis. Rice bran should be stabilized and typically has added calcium carbonate to balance its otherwise high phosphorus content. However, few rice brans are otherwise fortified, so are unlikely to help with the overall provision of other necessary essential nutrients. Some better-quality rice-bran products will have added vitamin E. This in part helps maintain the product’s shelf life; horses with higher fat intakes also have higher vitamin E requirements. For this reason, if you compare feeds that have, say, 6% versus 12% crude fat, you will typically find that the 12% crude fat feed has a higher vitamin E content.

It is tempting and easy to pour oil over an existing diet, which will certainly increase calorie intake; however, feeding large amounts of oil can backfire. If you overwhelm the small intestine’s ability to digest and absorb fat it will pass into the cecum and large colon where it can disrupt fiber fermentation. This could actually result in weight loss as the horse would not be able to get as much nutritional benefit from the forage in the diet. With very high intakes or sudden introductions of larger amounts of oil, manure can become oily. For these reasons, introduce oil slowly over 10 to 14 days, increasing by no more than a quarter cup every two to three days until you reach the desired amount.

Oils all have different compositions of fatty acids, and recently omega-3 versus omega-6 fatty acids have gained a lot of attention. This is because these fatty acids play important roles in cell membrane fluidity, inflammation, and immunity. Both are necessary for these important functions, but relative amounts of each might influence overall response. As a result, corn oil is no longer as desirable as those oils with higher omega-3 contents such as canola oil. Flax oil and camelina oil provide more omega-3 than 6 fatty acids and are good choices; however, in large amounts cost might be inhibitive.

An 8 fluid ounce measuring cup holds approximately 200 g of vegetable oil, which provides 1.8 Mcal of digestible energy, which is about 10% of a 500 kg (1,100 pound) horse’s maintenance requirements and is comparable to the energy provided by just over a pound of oats. Even though the horse’s natural diet is relatively low in crude fat, horses appear to utilize fat well and have been fed up to 230 g of fat per kilogram dry matter consumed as corn oil. However, the National Research Council cautions against feeding soybean oil at intakes exceeding 0.7 grams per kilogram body weight per day. Therefore, it is likely best to keep supplemental oil intake at no more than about 2 cups per day for an average sized horse.

Lastly, consider whether increasing fat is actually the best feeding option for preventing weight loss in winter. Many horses lose weight in the winter due to the additional calorie expenditure used to keep warm. Feeding extra hay not only increases calorie intake but also generates internal heat due to the fermentation process necessary for digestion in the horse’s hind gut. Therefore, increasing forage for horses that have good dentition is always my first choice.

Q: Should I give my horses warm drinking water in the cold weather? What are the pros and cons of warm drinking water versus cold during the winter?

A:  Drinking water is one of the most important aspects of horse care in any season, but during the winter, providing fresh water can be particularly challenging due to freezing temperatures. Horses do not seem to mind drinking cold water: however, research shows that overall consumption decreases as water temperature drops. Researchers have also noted that if given the choice of cold and warm water, horses will preferentially drink the cold water. This becomes a problem if, through their choice, they are drinking less than they would have if only warm water been available. The ideal temperature for drinking water is 45-65 degrees Fahrenheit, but it can be made warmer if consumption remains low.

Decreased water consumption increases the risk of impaction colic, which is a major health concern and a leading cause of death. Therefore, take steps to maximize water consumption throughout the year. If you live in a cold climate where water freezes, having the ability to offer warm water is a good idea. This could be in the form of heated water buckets, insulated regular buckets, or adding boiling water to cold water to raise the temperature even for a short period.

If it is not possible to offer warmed water around the clock, consider making it available for a period of the day, such as overnight if horses are brought into stalls. Remember that if cold water is also available, your horse might choose to drink that rather than take advantage of your efforts to provide warmer water.

Researchers at the University of Pennsylvania have shown that heating water continuously versus providing ambient near-freezing water increases horses’ water consumption by 41%. They noted similar results (38% increase in consumption) when warmed water was provided twice a day versus continuously. Video footage showed the studied horses consumed most of the water within three hours of feeding. Consuming forage typically creates a drive to drink. Therefore, this might be the most opportune window in which to provide warmed water. Other important thirst stimulants that can help encourage water consumption include adding salt to feed rather than relying solely on salt blocks.

As to whether drinking cold water is dangerous, this is a myth that should be cast out. Allowing horses to drink cold water will not have negative health implications. Another winter water myth is that horses will gain the water they need by eating snow. This is very unlikely, as the water content of snow can be quite low, and it is just not feasible for it to meet horses’ need to consume 30 to 50 plus liters a day.

Do you have an equine nutrition question? The Horse’s editors want to hear from you! Send your questions to editorial@thehorse.com.

Q. I have a small farm with only four horses, but I like to buy feed and hay in bulk to reduce the number of trips to the feed store. What is the best way to store each, so they stay fresh for my horses and maintain their nutritional value?

A. Buying grain and hay in bulk for horses offers several benefits. It can not only reduce trips made to the store but also save you money. However, disadvantages include potential loss of nutrient content, increased incidence of spoilage (often from mold), and potential infestation of vermin or bugs. Spoilage and pest infestation can potentially make your horse ill, so always be observant for any issues.

Storing Horse Hay in Bulk

Horse owners most often buy square-baled hay in bulk because it can last for a year or more with minimal nutrient loss if stored properly. Keep hay in a dry environment, off the ground. Wooden pallets are a common and inexpensive way to provide space between the hay and the ground. If you need to store hay outside, lay waterproof tarps over it. In any storage situation, although you might be tempted to stack and pack hay bales tightly, you need to have airflow around the bales. This will help prevent moisture accumulation, either from absorption from the ground or leaks in the roof, which can cause hay to mold.

Closely monitor recently harvested hay for heat. As hay dries and cures it will become hot and, if it reaches a critical temperature of 150-170 F, it can combust. Ideally, hay should not get hotter than 120 F during the curing process. If you buy recently harvested hay, stack it loosely so heat doesn’t accumulate between bales. You can purchase a hay thermometer to monitor the temperature. Pull any bales that reach 150 F. Excessive heat can accumulate when hay is baled wet, with a moisture level of 25-35% moisture, instead of the ideal 16-20% or lower. If possible, store hay in a separate building away from the barn to reduce the risk of barn fires due to hay combustion.

Storing Horse Feed in Bulk

You can buy commercial feeds in bulk, but they have a shorter shelf life than hay. In ideal conditions (dry and a moderate temperature), bagged feeds can often be stored for 30-60 days, on average. In cooler and drier conditions you might be able to store it for four to six months. In hot and humid weather the storage time decreases to about three to six weeks, unless you store them in a cool (air-conditioned) space. Like hay, keep bagged feeds off the ground, such as on pallets. You can also keep them in rodent-proof containers. Once bags are open, keep them in a rodent-proof bin and feed them within two weeks. Monitor all feed for mold.

Feed manufacturers put production dates on their bags, and some will include a “feed by” date. Learn how to read this coding because feed that has been stored at the mill or feed store will have a shorter lifespan at your farm. Pelleted feeds, due to processing and heat treatment, tend to last longer in storage than feeds containing molasses and oils.

With both hay and feed, adopt a first in, first out mentality. Make sure to rotate feed and hay so you use the oldest first. If your providers are delivering feed to the farm and stacking it for you, be sure they rotate the bags, keeping the older ones on top or moving them out of the way.

Take-Home Message

Buying feed and hay for your horses in bulk might help you save money. However, you need to have adequate storage space to keep feeds out of the elements and extreme temperatures. Keep stored hay and grains off the ground so they don’t accumulate moisture and then mold. Make sure you can use up your concentrates before the expiration date (or shortly after), and store opened feed in rodent-proof containers.

Q. I have an overweight pony I started on a weight-loss program recently. I know a good way to ensure I’m giving him the right amount of forage is to calculate the weight of the forage as a percentage of his body weight. Should I calculate this based on his current (overweight) body weight, or his ideal body weight?

A. It is excellent that you realized your pony should be on a weight-loss program. Ponies, even more so than horses, are often easy keepers, which means they metabolize feeds efficiently, making them prone to obesity and related health challenges. I would strongly encourage you to have your veterinarian evaluate your pony for potential metabolic issues to make sure you aren’t fighting a more complicated problem.

Calculating Equine Forage Intake

There are a couple trains of thought about weight reduction and how to calculate desired feed intake on a percent of body weight basis. The common thread running through all these methods is that reducing caloric intake is key to weight loss. I would recommend no matter what method you choose, you come up with a way to consistently and objectively evaluate your horse’s weight, be it pounds of body weight or inches (or both). Also consider how you can increase his calorie expenditure, or the amount of exercise he gets in a day. A combination of decreasing calorie intake and increasing calorie expenditure will produce the best results.

One common recommendation from nutritionists is to feed the horse or pony 1.5% of their current body weight in forage. The other is to feed him 2% of the desired body weight in forage. Since you did not give the type of pony or his current weight, I am going to show example calculations for a 14-hand Welsh pony that weighs 850 pounds with an ideal weight of 750 pounds. Using the 1.5% of current weight method, he should eat approximately 13 pounds of hay per day. Fed at 2% of desired body weight, he should eat 15 pounds of hay per day. You did not mention how much you currently feed, but I would caution against dropping the amount too quickly or drastically. Always feed at least 1.5% of the horse’s current weight, unless a veterinarian directs otherwise. Restricting forage too much can induce hyperlipidemia (an excess of lipids in the bloodstream), cause insulin resistance issues, and lead to stereotypies such as wood chewing.

Other Factors in Equine Weight Loss

Reducing the amount of forage offered per day will help your pony lose weight, but it’s also important to consider the type of hay you’re feeding. It should be a more mature grass hay with a neutral detergent fiber (NDF) level of between 50% and 65%. A measure of insoluble fiber, the higher the NDF, the fuller your horse will feel, decreasing his appetite (similar to when people trying to lose weight increase their fiber intake. Having your hay analyzed is the best way to determine the NDF content. Avoid immature grass hay and legume hays, because they usually contain more calories than your pony needs.

Also ensure your pony doesn’t consume his allotted hay too quickly. You can accomplish this by feeding flakes of hay every few hours or dividing the hay into multiple meals. You can also invest in a hay net with very small holes, or even put your hay in multiple nets, to make it more challenging for your pony to pull out the hay.

Take-Home Message

Adjusting the amount and type of hay your pony eats can help him lose weight efficiently and safely. Make sure to monitor your pony’s weight loss carefully. Once he reaches the desired weight you might need to increase his hay intake to help him maintain a healthy weight. Work closely with your veterinarian and an equine nutritionist to ensure your pony does not have any underlying health conditions, and confirm his diet meets his nutritional needs.

Q. I’ve heard that alfalfa is a good hay choice at night for horses because it helps generate heat and keep them warm. Where I board my horse, the barn managers feed grass hay at night and told me that it keeps horses full longer. So, which is better for winter night feedings: grass or alfalfa hay?

—Julie, via e-mail

A. As we head toward the colder winter months, you’re not alone in wanting to make sure your horse stays warm overnight. When temperatures drop, feed requirements increase for your horse to consume enough calories to maintain condition. Staying warm requires calories beyond those needed for regular maintenance. Horses have different ways to regulate their body temperature depending on the ambient temperature, wind chill, and other climatic challenges they face.

Thermal neutral zone is the range of temperatures at which metabolic heat production doesn’t need to be altered to remain thermally neutral. When temperatures drop significantly, horses cross a boundary known as the lower critical temperature (LCT). Below this temperature, horses need to increase their metabolic heat production to maintain body temperature. Similarly, an upper critical temperature (UCT) exists, above which measures are taken to reduce heat production.

At exactly what point horses cross into the LCT varies based on a number of things, such as age, whether their coat is clipped, and the weather conditions they’re used to. Upon reaching LCT, the question becomes what form of extra calories should you provide your horse? It might be tempting to increase horses’ daily grain intake because it’s the simplest way to add more calories. However, as you have heard, feeding more hay might offer advantages.

Forages such as hay require microbial fermentation in the hindgut to maximize their use in the digestive tract. This isn’t a completely efficient process, and fermentation results in energy being lost as heat. This heat acts as an internal central heating system, helping keep your horse warm. Thus, any kind of forage can help keep your horse warm in winter. Less digestible types might result in greater amounts of heat being produced.

Because grass hay is a lower-calorie hay, you can feed horses larger rations of it than you can alfalfa hay, especially with easy keepers. Many people do believe alfalfa is the best hay to feed in winter for warmth. I suspect this is due to alfalfa’s high protein content and the fact that metabolizing protein isn’t the most efficient process—thus, it generates metabolic heat. Another reason is that people misguidedly believe protein is a good energy source.

Horses tend to eat grass hay slower than alfalfa, and so there’s the possibility that grass hay will last longer during the night, resulting in a more continuous stream of fuel for the fermentation process. The bottom line is both types of hay will result in microbial fermentation in the hindgut. It comes down to which is the best type of hay for your specific horse. While in some cases I will pick the alfalfa, more often than not I choose to feed more grass hay.

Q: My 25-year-old gelding has pituitary pars intermedia dysfunction (PPID, formerly known as equine Cushing’s disease) and a history of laminitis. During the winter he struggles to maintain a healthy weight. I’m worried about feeding him too much due to his PPID and laminitis history, but it can be hard to help him maintain his condition through the colder months without additional feed. What can I do to help him maintain a healthy body condition score (BCS) during winter without putting him at risk of another laminitic episode?

A: When managing horses with PPID, it is important to monitor their weight consistently. It is great that you are proactive, looking at what you can implement to support your gelding before the cold weather arrives. Caring for these horses successfully depends on managing their nutritional and medical needs effectively.

Horses with PPID commonly struggle to maintain a healthy body condition, and they frequently struggle to sustain their muscle tissue. When a horse is underconditioned, it can be tempting to add extra commercial feed to his program. Be very cautious doing this, however, because PPID horses are at a greater risk of developing the painful hoof disease laminitis and are sensitive to starch and sugar in the diet.

Due to your gelding’s health and his history with endocrinopathic laminitis, you should most likely maintain him on a diet low in both starch and sugar but that still provides adequate calories.

Starch and Sugar in Horse Diets

The carbohydrates starch and sugar can be either hydrolysable or fermentable, depending on if the horse can break them down enzymatically. If not, the horse ferments them in the hindgut. The general rule of thumb for feeding horses with metabolic issues is to ensure that hydrolyzable carbohydrates (HC) make up no more than 10% of their diets.

If your gelding can still chew and consume hay properly, offering free-choice hay with less than 10% HC could help him maintain his weight during winter. Before feeding new hay to your horse, always have it analyzed. You cannot accurately estimate hay’s sugar content by looking at it, so untested hay can be risky for horses with metabolic issues. 

Along with hay, provide your horse a high-quality ration balancer, low in starch and sugar, at the recommended rate for his weight to ensure he gets the necessary vitamins and minerals daily.

Adding Calories to a Metabolic Horse’s Diet

To supplement his daily ration with additional calories, offer products such as forage pellets or cubes, unmolassed beet pulp, fat sources such as ground flax or oil, and low-sugar commercial feeds.

Occasionally, hay low in starch and sugar is overly mature and, therefore, provides less calories. In these cases you can offer soaked fiber sources such as hay cubes or beet pulp, which are highly digestible, for additional calories. Typically, older horses have an easier time chewing these.

Owners can also use oils and fats for horses with metabolic issues. These products are calorically dense but not digested the same way as carbohydrates and do not impact blood insulin. Introduce fats slowly because horses do not have a gallbladder (which stores and concentrates bile that aids in the digestion of fat). Camelina, flax, hemp, and ahiflower oil are all great examples of fat sources that can be added to increase your gelding’s calorie intake safely. You can also use powdered fat supplements available on the market.

Take-Home Message

Adding calories to a metabolic horse’s diet without risking a laminitic episode can be challenging. Always begin by ensuring you’re meeting your horse’s base nutrient requirements with a safe hay and high-quality ration balancer. From that point, consider using soaked fiber sources and fat to provide additional calories.

Q. My horse needs daily medication. Do you have any tricks for giving him the pills in a manner that he might actually enjoy?

A. Giving medication to your horse can be a challenge. Given the size of their muzzle, their ability to weed out and leave a tiny pill in a bucket of feed is impressive! For some horses, especially those being fed a textured feed, owners get lucky and find that they can just put the pill in the feed and the horse eats it just fine. But in my experience these horses are the exception, not the rule.

Most owners are left trying to find something that they can put the pill in and hand feed that won’t illicit a response from the horse that indicates he thinks you’re trying to poison him.

Here are some things you can try that might do the trick.

Soft horse treats

Many slightly squishy horse treats are available at local feeds stores and online, and they’re often very palatable and easy to press a pill in to.

Apples and carrots

Classic favorite treats, some owners find they can hollow out a small hole and press a pill into a piece of carrot or apple and successfully feed it this way.

Pill pockets/pouches

Several brands of pill pockets and pouches are on the market designed specifically for horses. Most are quite palatable; however, they might be more expensive than other options.

Pitted prunes

While plum pits are poisonous to horses, prunes (the dried plum fruit) are safe to feed and make fabulous pill pockets. They are sweet and sticky and do the job nicely.

Water

Most pills and tablets dissolve in water. If you place the necessary medication in a syringe, add water, and let it sit it should dissolve and then you can dose the horse orally. You might need to crush very hard pills first. Administering this way takes some skill to ensure the liquid with the pill goes down their throat and not out the side of their mouth.

Dietary Considerations

A good number of horses needing daily medication are those with pituitary pars intermedia dysfunction (PPID, or equine Cushing’s disease), and veterinarians generally recommend these horses eat low-starch, low-sugar diets. The same is true for horses with other metabolic conditions where a low non-structural carbohydrate (NSC) diet is required. This adds a level of complexity to medication administration as many of the above options are not necessarily low in sugar.

It is important to know your horse’s sensitivity and to keep in mind the actual amount of sugar you’re providing in one treat. For example, the USDA’s food products database indicates that a mini bite-sized prune contains 2 grams of sugar, a single baby carrot contains about 1.33 grams of sugar, and a 7-inch-long carrot has about 5 grams of sugar. Compare those figures to a half-cup of applesauce (administered with a syringe), which can range from about 10 grams to 20 grams of sugar, and you’ll see a single prune or carrot is probably a better option. Treat manufacturers will often be able to tell you their products’ sugar and starch content even if it’s not on the label.

Some treats, pill pockets, and pouches on the market are low-NSC and likely the best options for sugar-sensitive horses. For horses with conditions like PPID, though, sometimes the risk of feeding one slightly higher-sugar treat to get the needed medication dose required to control the condition vs. the horse refusing to take the pill, a small amount of sugar is the lesser of two evils.

If you have concerns about whether a method of dosing is appropriate for your horse check with your veterinarian.

One last consideration for success is how you approach your horse when you present the treat. Medicating horses can be stressful, especially if they’ve refused other methods you’ve tried. However, approaching your horse holding your breath and nervously trying to anticipate the outcome is a recipe for disaster. Your horse will read your body language and know something is up. Try to stay upbeat and positive.

Q: I’d like to make some festive holiday horse treats as gifts for my friends, and it seems like everything is pumpkin flavored this time of year. Is it okay for horses to eat pumpkin and/or pumpkin-flavored treats?

A: The short answer is yes! Orange pumpkins are safe to feed horses, and this includes the seeds. However, avoid generalizing that all squashes and pumpkins are okay for horses to eat.

When feeding fruits and vegetables to horses the first consideration is whether the item is toxic to them; remember, horses cannot safely consume all the same things we humans can. Check lists of poisonous plants and foods provided by universities such as Cornell, as well as sources such as the American Society for Prevention of Cruelty to Animals, to see what you can find out about the item.

Next consider what we know about the item’s nutrient profile to determine if it is a sensible choice to feed horses. (You can look up a lot of data on foods at Self Nutrition Data.) This is particularly important for horses with metabolic conditions, because knowing a food’s glycemic index and load can be important to preserving your horse’s health. Many of us are familiar with glycemic index, which compares the potential for foods containing the same quantity of carbohydrate to raise blood glucose. However many foods might not actually contain very much of these high glycemic carbohydrates, which makes knowing glycemic load useful.

Glycemic load multiplies the glycemic index by the amount of carbohydrate, in grams, provided by the food and then divides it by 100. While pumpkin has a glycemic index of 75, meaning that the blood glucose response to eating a set amount of carbohydrate from pumpkin is 75% of the response to the control, its glycemic load is only 3. This means that it will not cause a rapid increase in blood glucose, especially when eaten in limited quantities. This makes it a safe choice for horses with equine metabolic syndrome and conditions such as polysaccharide storage myopathy.

In the scheme of human foods pumpkin has a relatively high potassium level, providing about 0.4 grams per cup. In the context of the typical equine diet where an average grass hay is providing 8.5 grams per pound, the amount in a sensible serving of pumpkin is likely nothing to worry about. However, if you have a horse with hyperkalemic periodic paralysis, where you are trying to limit potassium intake, it might be wise to skip the pumpkin treat.

Pumpkin seeds are often touted for their health benefits, and certainly human-focused research in the scientific literature suggests they might have benefits thanks to their positive impact on nitric oxide levels. Nitric oxide is an important cellular signaling compound and powerful vasodilator. We don’t know what the benefits might be to horses, but there are lots of anecdotal discussions online about the potential benefits.

Before you go throwing the decorative pumpkins from around the barn to your horse at the end of the season, please do use common-sense. Don’t feed horses pumpkins that might have candle wax in them or that have started to rot. Also consider that it’s never wise to suddenly add large amounts of a novel food to your horse’s diet. With that in mind keep pumpkin intake to a couple of cups a day or about one small pumpkin.

Try suspending a smaller dessert (or pie) pumpkin as a stall toy. This could also make a cute gift for a friend’s horse. Alternatively, cook the pumpkin and use the softened flesh to make horse treats. Try combining cooked pumpkin with oats, wheat bran, a little cinnamon, and molasses until gooey and baking at about 300^oF  for at least 20 minutes. Note that treats with oats and wheat bran aren’t suitable for horses with metabolic issues. If all this sounds like a lot of bother, just put the pumpkin in your horses’ stalls whole for them to play with, or cut into pieces and add to their regular feed. Just remove the stem as it may be a choking hazard.

Q. I recently purchased an obese pony, whom I estimate needs to lose more than 100 pounds. I know changes in weight should happen gradually, and I’ve heard rehabilitating starved horses needs to be done carefully to avoid refeeding syndrome. Are there similar concerns when rehabilitating an overweight horse to their ideal weight?

A. Good for you for recognizing your new pony is not at a healthy weight and needs a plan to get there. To help your pony lose weight, you need to put him in a state of negative energy balance where the energy consumed is less than the energy he uses each day. This will cause him to utilize stored energy reserves to make up the difference, resulting in weight loss.

The problem with being in negative energy balance is it can cause excessive mobilization of body fat into the bloodstream. The purpose of releasing these fatty acids is so the liver can metabolize them into glucose (gluconeogenesis) or package them into triglycerides for further transport in the blood. In and of itself this is not an issue; in fact, it’s a perfectly viable way for the body to use energy stores. The problem arises if too much fat is mobilized, especially in horses predisposed to hyperlipemia (the disease caused by hyperlipidemia, or the abnormally high concentration of fats or lipids in the blood).

This condition is the result of too much fat in the bloodstream. Normal triglyceride levels in the horse are below 100 mg/dl; however, during hyperlipidemia levels can be above 500 mg/dl. This fat buildup in the bloodstream can cause the liver to stop functioning properly and a condition known as hepatic lipidosis. Toxins then build up in the blood, and the horse might start feeling unwell, a side effect of which can be going off food. Of course, going off feed only acts to exacerbate the problem.

In the early stages of hepatic lipidosis, the clinical signs of lethargy and going off feed can be easy to miss. Often, owners wait to see whether the horse starts to eat again, not realizing what is going on. But this wait-and-see approach can be fatal for the horse. The condition can quickly progress to liver failure, jaundice, staggering, colic, and an inability to get up. Even when caught early, prognosis once hepatic lipidosis occurs can be poor, with 40 to 80% of horses dying as a result.

Therefore, careful weight loss is vital, and I recommend working with your vet to coordinate a plan. Regular bloodwork might be indicated to ensure blood triglyceride levels are not reaching dangerous levels. Additionally, horses that have insulin dysregulation issues tend to be predisposed to hyperlipemia and, in turn, hyperlipemia can exacerbate insulin resistance. With high circulating insulin being a potential trigger for laminitis, it’s important to monitor metabolic status, as well.  

Understand that this isn’t just a “fat pony” condition. It can occur any time a horse goes into negative energy balance for a prolonged period. This includes during pregnancy and lactation if the foal is drawing large amounts of energy off the mare and during severe illness that reduces or eliminates appetite, such as colic or fever. Any time a horse goes off feed, especially when combined with one of these scenarios, it is worth contacting your veterinarian.

Q: My 10-year-old reining horse is an easy keeper and a 7 to an 8 on the body condition scale. My veterinarian recommends he lose weight to prevent other problems later in his life. What tips do you have for helping him lose weight but still supporting him with the nutrients he needs? 

A: Too often I have observed horse owners who believe having a “pleasantly plump” horse is overall healthier than he might be without the extra pounds. Several studies and reviews have been published estimating 40% to 50% of horses in the United States were considered obese. 

Body condition scoring measures the amount of fat on horses. Although you can use several methods to assess body condition score, the one most people use is the Henneke system, which has a range from 1 (poor/emaciated) to 9 (extremely obese). It allows you to evaluate fat cover across six regions of the body. Most horses should be in the range of 4 to 6. So, your horse at a score of 7 to 8 is on the overweight to obese side. When evaluating your horse’s body condition, be sure to do so consistently, always using the same method for the best assessment. 

As your veterinarian mentioned, carrying excess weight can be detrimental to your horse. Excess weight will cause wear on joints, tendons, and ligaments. It can predispose a horse to bouts of osteoarthritis and other joint problems and laminitis. Overweight horses might also develop muscle strain injuries. In addition, excess fat can make it difficult for a horse to regulate his body temperature, which will lead to dehydration, poor performance, and heat stress. So, shedding some excess fat could help your horse have a more successful and longer athletic career. 

Facilitating Safe Equine Weight Loss 

If your horse doesn’t have a medical condition that predisposes him to being overweight, your goal is to decrease the caloric density of his diet and/or increase his exercise. I often advise an increase in turnout time, with the horse wearing a muzzle, or developing a turnout system that requires the horse to walk from one resource to another (for example, placing small amounts of hay in multiple locations). You could include additional exercise, such as trail riding or time on a hot walker. However, with your reiner, especially if he’s wearing plates (a special shoe designed to help reining horses slide well), it might be difficult to incorporate this.  

I would suggest working on limiting his calorie intake. Source a good-quality grass hay as the base for his diet. He should receive a minimum of 1% of his body weight in forages. Grains and concentrates tend to be very calorie dense, so you might need to decrease the amount you’re feeding to reduce his calorie intake. Choose a high-quality ration balancer to meet his nutrient needs. These are a concentrated source of vitamins, minerals, and possibly amino acids, depending on the product, designed to be fed in relatively small amounts. Ration balancers are a great way to help meet nutrient requirements without additional calories, like daily multivitamins for humans. 

Take-Home Message 

You should routinely monitor your horse’s body condition to evaluate his weight loss. Also, work with an equine nutritionist to be sure your horse receives the nutrition he needs daily and loses weight in a safe way. Keeping your horse at a healthy weight can decrease his risk for other health conditions, such as joint disease and heat stress, and improve his performance. 

Do you have an equine nutrition question?

Q. I have a herd of five horses, all of which have histories of some kind of metabolic problem or laminitis. They are at healthy weights, but I do currently soak their hay. During the winter months (which are well below freezing where I live), what are some alternatives to soaking their hay?

A. This is a great question, and you are right to want to reduce sugar as much as possible in your herd’s diet. I’m based in Ontario, Canada, so below-freezing temperatures are a hurdle to soaking hay that I know well.

When discussing the nutritional management of horses with insulin dysregulation, my first recommendation is testing their forage. If you are nearing winter and continually soaking hay, I strongly encourage you to test your hay to determine its exact sugar content.

Soaking hay for 30-60 minutes before feeding is often a recommended practice for horses presenting with metabolic challenges when the nutritional content of the forage is unknown. It is also a popular management practice for reducing the sugar content of high-sugar forage. Therefore, when managing these cases, it is crucial to have the forage analyzed so you are equipped with all the nutritional information. Additionally, I would encourage consulting a nutritionist to ensure your horses’ nutrient requirements are still being met while maintaining a low sugar ration. The idea of reducing sugar in the diet is to avoid elevated insulin levels, so reducing any source of sugar is optimal.

If you are soaking your hay because the analysis results indicated high non-structural carbohydrate (NSC) content, I have a few recommendations to consider as we quickly approach the colder months. Make it a priority to talk to your veterinarian and discuss the safety of discontinuing soaking the hay. If your horses were quite overweight when they experienced laminitis issues, their risk level might be lower now. Insulin testing is also an important topic to discuss with your veterinarian, because the results will help guide your decisions regarding your horses’ forage intake.

Another option could be to purchase lower-sugar hay to combine with your current hay and feed your herd a mixture of the two forages to reduce the overall sugar content in their daily ration.

If your hay has tested high in sugar and purchasing more is not feasible, soaking hay in below-freezing temperatures isn’t realistic, so we need to find other ways to reduce the overall sugar content of their daily ration. Steaming can be a popular method; however, it is not as effective at reducing sugar content, and the equipment can be a significant investment. If you would like to investigate steaming, I encourage you to also test the steamed forage to ensure it will be safe.

A temporary solution to get you through the colder months would be to replace a portion of your horses’ hay with a preserved forage such as timothy hay cubes that have an NSC content less than 10%. This will decrease the overall sugar content of their ration to reduce the risk of metabolic complications.

Soaking hay as a long-term solution can be challenging, especially in colder climates, so I strongly encourage investing in additional hay testing. If you’ve explored all routes of altering hay and they’re unattainable, then I would suggest consulting a nutritionist for help reducing sugars in the ration, exploring steaming, or replacing a portion of the forage with a low-sugar option such as timothy hay cubes.

Q. I compete with my horse in the jumpers year-round. I know that it is advisable to feed a small meal before riding to prevent ulcers, but what is the best practice for showing? Should I feed my horse a small meal before he shows? If so, how far in advance and what would be best to feed him (forage vs. concentrate, etc.)?

A. It is great that you are thinking about preventing ulcers, or at least decreasing their severity, before they start.  Studies have shown that 60 to 90 percent of performance horses have ulcers. Unfortunately, typical show horse management practices, including stall confinement, higher-concentrate (grain) diets, travel to new venues, and stress level, can contribute to ulcer development. Horses that develop ulcers often exhibit nervous or aggressive behaviors, sensitivity in the back or girth area, teeth grinding, decreased appetite and poor performance. They might also lie on their backs in their stall, which seems to alleviate some of the pain associated with gastric ulcers. 

Gastric ulcers occur when acids produced in the stomach, such as hydrochloric acid, come in contact with the wall of the upper stomach (called the squamous region). This region does not have a protective mucus layer, like what is found in the lower, glandular region, which is where acids are secreted. In performance horses this often happens during exercise. Feeding practices, such as infrequent meals, can leave the stomach empty; however, horses are designed to eat small, frequent meals and secrete acid constantly. An “empty” stomach, which occurs when meals are quickly digested and separated by several hours, is more susceptible to developing ulcers. 

There are several things you can do, from a dietary standpoint, to help lessen the incidence of ulcers at shows and at home. If you are feeding a concentrate, divide it into multiple small meals throughout the day to decrease stomach acidity (more on why this helps in a moment). You could also switch to a feed higher in fat, which can help to decrease stomach acidity. Your horse should have access to high-quality forage throughout the day, and hay containing a legume, such as alfalfa, will be higher in calcium, which is a natural buffer for stomach acid. From a management standpoint you should hand-walk and hand-graze your horse—or even give your horse some turnout in a paddock, if available—to help decrease your horse’s stress levels, and provide him with more forage. 

You are correct that feeding a small meal prior to competing can help prevent ulcers. However, you need to be careful regarding what you feed. A grain meal is not advisable, but owners should avoid filling the stomach with a large hay meal. A good alternative is to feed about a pound of chopped forage 30 minutes prior to competing. This will provide a few advantages: it will fill the stomach so it is not completely empty, and the forage will also essentially form a cover which will float on top of the acidic fluids and can keep the acid from splashing on the squamous region.  

If you have any concerns that your horse has ulcers developing, consult your veterinarian. There are medications containing omeprazole and some natural supplements that can help heal the ulcers, and most horses respond positively with improved attitude and better performance. You should also speak with a nutritionist to make sure you are meeting your horse’s dietary needs and minimizing the potential for ulcer development. 

Q: My 10-year-old gelding is extremely quiet. We show in the hunters, but he just seems to lack impulsion and doesn’t react to my cues most days when I ride, whether we’re at home or at a show. We’ve ruled out serious health concerns such as ulcers or musculoskeletal pain. Is there anything I can change in his diet to help with his energy levels?

A: When you have behavioral concerns about your horse, always have your veterinarian examine him to rule out any health issues—as you’ve done—prior to exploring diet changes. Each horse is incredibly unique, their behaviors and personalities can vary widely, and a multitude of factors can influence demeanor, from genetics, health, environment, and training to, of course, nutrition.

Making diet modifications that encourage more rapid energy releases might help improve your horse’s energy levels. A variety of feed types can provide our horses with more energy, including fiber, starchy grains, and fats. The way these feed types are digested and metabolized will determine how they influence the horse’s behavior. While many horse owners avoid any products that could make their horse excitable, there are times when adding feeds that provide a rapid source of energy can be beneficial.

Types of Energy Sources for Horses

Horses commonly consume three types of carbohydrates: hydrolysable, rapidly fermentable, and slowly fermentable. They digest hydrolysable carbohydrates, which include simple sugars and starches, in the foregut. Their digestion leads to an immediate rise in blood glucose and insulin, creating a spike in energy typically occurring 60-90 minutes after the horse eats. 

Grains high in starch, such as corn, barley, wheat, and oats, cause this spike in energy. This type of energy provides quick calories, but doesn’t support sustained endurance in horses. Feed these grains in small quantities to reduce the risk of gastrointestinal issues. If fed in large amounts, they can pass through the foregut rapidly, and the starch will reach the hindgut, causing a drop in the pH that results in microbe death.

Fiber typically comprises most of a horse’s meal because his gastrointestinal tract has evolved to consume fibrous feeds. Common examples of these feeds include hay, pasture, beet pulp, and cubed or pelleted fiber sources. They provide the horse carbohydrates that are mostly fermented in the hindgut. Microbial fermentation produces volatile fatty acids (VFAs), which are gradually released because horses digest fiber slowly. Although fiber serves as a significant calorie source for the horse, it does not result in that same immediate blood glucose spike seen with starchy grains.

Fats and oils can also be a “cool” energy source because they have a slower energy release. If you want to add more rapid energy to your horse’s diet, incorporating a small number of grains can be a good option, but remember that a high-quality forage and a ration balancer should make up the majority of his diet to ensure he receives the fiber and nutrients he needs.

Electrolytes for Energy in Horses

If your horse feels sluggish, he might have an electrolyte imbalance. When a horse receives the appropriate amount of electrolytes in his diet, he takes a longer time to fatigue and recovers faster from exercise. For the average-size horse, owners can feed about 2 tablespoons of loose salt daily. On days the horse sweats more, he might need additional electrolytes to support hydration and fluid balance.

Developing a Feeding Program for Sluggish Horses

When designing a balanced nutrition program to support your gelding’s energy and performance, start by selecting a high-quality forage option. Adding some alfalfa might be a good choice because it would supply him with excellent protein and more calories. Then choose a high-quality source of vitamins and minerals; a ration balancer often works well. However, if the horse struggles to maintain weight, a performance feed could offer the additional calories needed. To boost energy add a grain-based product in small amounts because this will provide quick energy he can rapidly digest.

Take-Home Message

When dealing with behavior concerns such as lethargy, first consult your veterinarian because pain is a common cause of reduced energy and poor performance. Work with a qualified equine nutritionist to ensure your horse receives a balanced diet with adequate calories for his workload. If his basic nutritional requirements are being met, a feed rich in hydrolysable carbohydrates that are rapidly digested might help improve his energy levels. Please note that grain-heavy diets increase the horse’s risk of gastrointestinal issues such as hindgut acidosis, so keep the amounts small and always make diet changes over one to two weeks.

Q: My 8-year-old mare’s body condition score (BCS) tends to fluctuate depending on the season. She often stays around a 5 or 6 BCS during the warmer months but drops to a 4 as the weather gets colder. She is fed a balanced diet and is turned out overnight year-round. Her workload decreases during the coldest months of the year. Is it concerning or indicative of a problem that her BCS fluctuates like this? What can I do to combat it?

A: Weight loss in the colder months commonly occurs because horses need more calories to stay warm. They can use up to 25% more energy to maintain adequate body temperature. Several other factors can influence your horse’s energy requirements, such as housing, age, and environment.

Track Your Horse’s Body Condition

The Henneke body-condition-scoring system involves palpating six body areas—neck, withers, shoulder, ribs, back, and tailhead. I recommend performing this on your horse every two weeks to track her body condition and make sure you are not misled by her winter coat, which can make her appear fatter than she is.

Some weight fluctuation in the colder months is normal, and occasionally encouraged with easy keepers that tend to become overweight in the spring and summer. However, if your horse maintains a healthy condition through the summer but drops to a BCS of 4 in the winter, she likely needs supplemental calories to support a BCS of 4.5-5.

If you notice unexplained weight loss in your horse, first consult your veterinarian to rule out any health or dentition issues. From that point an equine nutritionist can help you make diet changes to combat the weight loss.

Use Forage to Help Your Horse Maintain Body Condition

The best way to keep a horse warm in the winter months is with high-quality forage. If your horse begins losing weight, first increase her hay. Free choice access to high-quality forage can help promote weight gain, especially in cold weather. The fermentation process that occurs in your horse’s hindgut when she consumes forage produces heat, which can help fuel her internal furnace and support thermoregulation.

Water for Horses During Winter

Many horse owners overlook water as an important nutrient during the winter. If horses drink less water, they don’t eat as much. Water offered to horses must be fresh, clean, and free from ice. If you live in a very cold climate, add a trough heater or other mechanism to keep the water from freezing and ensure your horse has continual access.

Supplemental Energy for Horses in the Winter

If your horse does not maintain her weight with an increase in forage intake and a balanced diet, you might need to consider adding a fat source. Horses do not have a gallbladder, but they can digest fat well if you introduce it slowly to their diet. Fat is more calorically dense than carbohydrates, which meaning it contains more than twice the amount of calories per pound. You can find numerous fat supplements to top dress your horse’s already balanced diet.

With this approach it will be easy to add and remove the fat product when the horse does not need additional calories.

Take-Home Message

In the winter you might notice your horse’s weight fluctuates slightly because she requires more energy to stay warm. However, you should not notice significant changes in her BCS. Horses always need access to fresh water and a high-quality hay source. If they still lose weight on a balanced diet with free-choice access to high-quality forage, consider adding a fat source for additional calories.

Do you have an equine nutrition question?

Most horse owners understand that internal parasites can cause poor condition in the horse. And most of us understand this is in some way due to these parasites “stealing” nutrients from the horse. While this is the case, the situation is potentially far more sinister.

Large strongyles, Strongylus vulgaris, live in the horse’s large intestine. Their eggs pass out of the digestive tract in feces and then hatch. Horses eventually consume the larvae, which pass through the intestinal wall into the various arteries that supply the digestive tract. Eventually, after several months, they return to the intestines as adults, and the cycle starts again.

Small stronglyes also reside in the large intestine, and their larvae migrate to and hibernate in the gut wall. When these larvae come out of hibernation, they can cause substantial damage to the gut wall. Some parasites, such as roundworms, are a greater issue for young horses, and the ingested larvae of these worms pass through the liver and lungs before maturing in the small intestine where their activity can cause substantial irritation and inflammation.

From a nutritional perspective, the problem with these parasites isn’t just that they’re stealing nutrients from the horse to survive, but that they are causing potentially permanent damage to digestive tract tissue and altering gut function.

The gut wall is vital to nutrient absorption. The first section of the small intestine, the duodenum, is responsible for secreting the many digestive enzymes needed to break molecules—such as sugars, starch, amino acid, and fatty acids—into their component parts. These are then absorbed into the gut epithelia in the subsequent jejunum and ileum of the small intestine. Damage to the tissues and scarring in these regions of the intestine can negatively impact cells that secrete enzymes, as well as those responsible for nutrient absorption. Parasites in the arteries of the intestinal tract could limit blood flow, reducing the amount of oxygen reaching intestinal tissue. Damage to vessels in this area might limit the nutrient movement away from the gut. This damage might be irreversible and could last a lifetime, resulting in a horse that’s a hard keeper.

In other species parasites are known to negatively impact the enteric nervous system (ENS), the integrity of which is necessary for gut homeostasis. The ENS is part of the autonomic nervous system. Autonomic nervous functions act largely subconsciously and regulate such things as heart rate, respiratory rate, and in the case of the ENS, digestion. When certain parasites impact the gut ENS in other species, gastrointestinal motility can be affected. In humans, conditions such as irritable bowel syndrome can result due to disruptions in the gut-brain axis.

If internal parasites impact horses’ ENS and, thus, gut motility, the horse might be at an increased risk of impaction colic if motility slows and poor nutrient digestion and absorption—and potentially diarrhea—if it speeds up.

The digestive tract’s main functions include digesting and absorbing nutrients, as well as serving as a barrier to potentially harmful agents, preventing them from entering the body. Internal parasites impact all these functions, both in the short term and potentially for the horse’s life. They’re not just robbing nutrients from the horse in that moment. They’re also creating a situation that might rob the horse of nutrients long after the parasites are gone.

Q: I have a fair amount of experience feeding senior horses. At one point I had three of them on either hay pellets or hay cubes due to dentition issues that prevented them from eating long-stem hay. Because they could consume the cubes or pellets fairly quickly, there would be long stretches during the day and night where there was no forage for them to eat; at that point, they started chewing wood in the barn and on trees.

I currently have two seniors, one of which will chew on his buddy’s hay and spit out the quids, so chew time is not a problem.  Before, I had one gelding who would not only chew his hay but would then eat other horses’ quids, which resulted in mild impactions throughout in the last two years of his life.

My question is: What can I do to appease the need to chew for equids that can only eat hay pellets or cubes, chopped hay, or complete feeds because their teeth are no longer effective for chewing long-stem forage?  Would small-hole haynets allow them to just get a few pieces of hay at a time to chew on while reducing the risk of impactions caused by swallowing unchewed long-stem forage?

—Karen, via e-mail

A: Chew time is an important consideration not just because it gives your horse something to do and more closely resembles the horse’s natural feeding behaviors, but also because chewing results in saliva production. Saliva lubricates the feed being consumed, helps its passage down the esophagus, and contains a significant concentration of bicarbonate and calcium—both of which buffer stomach acid.

Horses in a natural setting spend the majority of the day foraging and chewing, and they constantly secrete stomach acid whether they are eating or not. The near-constant chewing and saliva secretion continually buffers the secreted acid. The highly fibrous plant matter being consumed also buffers stomach acid and forms a floating mat on the surface of the acid, preventing it from splashing around.

When the horse spends less time chewing—whether its due to reduced forage intake, the type of forage, or the method of forage provision—he produces less saliva and can’t buffer the stomach acid as well. This could increase a horse’s risk of developing gastric ulcers in addition to developing undesirable behaviors such as wood chewing, as you’ve described.

Meal-feeding restricted amounts of hay reduces total chewing compared to the amount of chewing that would occur if the horse was on pasture full time. Many horses will consume a flake or two of hay in less than a couple of hours, leaving long periods between meal times with no chewing. Slow feeders can increase the time spent chewing and, thus, producing saliva.

For horses with poor dentition, long-stem hay might no longer be a viable option because they cannot chew it adequately. Hopefully, this results in quids—balled-up mouthfuls of partially chewed hay that fall out of the horse’s mouth. I say “hopefully” because the other option is that the horse swallows the inadequately chewed hay and is at risk of impaction colic should the hay get stuck in the gastrointestinal tract. Of course, the major downside to quidding is that the horse gets no nutritional value from the hay when it’s not actually consumed.

Some senior horses appear to chew hay fine, but don’t maintain or gain weight with it as they have in the past. This could be because they’re no longer as effective at digesting hay as they used to be. Some of these senior horses might develop loose manure due to mild colitis caused by the hay irritating the colon. I have worked with several such horses, and all have improved in body condition and manure quality by consuming a diet made up either partially or completely of hay pellets.

Hay pellets or cubes are a good solution for horses with poor dentition and other horses that might require pelleted diets, such as those described previously or with equine asthma that need dust-free or low-dust feed. However, because the hay has been chopped up to a very fine size prior to being turned in to the pellet, it takes very little chewing to break the pellets into an easily swallowed size. This results in reduced chew time and saliva production. If your horse eats a flake or two of hay in only a couple of hours, the time it will take him to eat a similar weight of pellets will be substantially less.

For your horse that reliably spits out quids when chewing hay, you could continue to give him access to a small amount of hay; however, I suspect that the majority of the saliva being produced during chewing ends up in the quid and not in the stomach. Additionally, there is the risk that some of the hay is being consumed and increasing impaction colic risk, so I would discuss hay-feeding strategies with your veterinarian. Small-hole haynets might result in better overall chewing and fewer quids, so this might be a good option, as well, but again I would discuss this with your veterinarian who can fully assess your horse’s situation.

A better solution might be an automatic pellet feeder—essentially, a slow feeder for pellets. There are several versions on the market. Basically, you fill the feed hopper with your hay pellets and program the feeder to release a certain quantity at your preferred time. Most of these feeders sit outside the stall and direct the feed into a bucket in the stall by way of a funnel. Some feeders will drop all the feed you want at once—for example, you program it to feed all 6 pounds of pellets at 7 a.m. Other feeders let you program them to feed that same 6 pounds of feed in intervals—for instance, you can program it to feed approximately 48 2-ounce portions every 30 seconds or so. These feeders allow you to spread your pellet meals at intervals throughout the day to simulate grazing.

You can use these same feeders to provide concentrates to horses that can eat hay, spacing their pelleted or textured grain meals in small portions throughout the day. They are also a great way to supplement a hay-based diet with hay pellets. For example, maybe you want to program it to feed some pellets at 6 p.m. in case you get home from work late.

You can find a number of automatic pellet manufacturers by doing an online search using terms such as equine pellet feeder.

Hopefully using a solution such as an automatic feeder will keep your horses eating more consistently throughout the day and prevent them from looking for alternatives to chew such as your trees or barn!