Equine Body Language

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Written By Walt Friedrich

Y’know, you can’t hide anything from a horse. He knows what’s going on in your mind. Sure, you know what he’s thinking, too, sometimes, but he seems to be so much better at it than you and I, doesn’t he?

Our horse has gotten so good at “mind reading” because it’s his natural “language” among other horses — and it naturally spills over into his communications with us. He doesn’t have to figure out what a “hard eye” is when he sees ours (and, of course, he doesn’t read our minds), he knows it very well because he’s seen it on other horses all his life. And that’s half of the communication transaction – that which we transmit. The other half is what he receives, or better put, how he perceives what he sees, and therein lies communication by body language! Of course it’s his natural language – raised in his natural environment among other horses in his herd, it’s the only language there is. He learns to read and comprehend the most subtle of signals, and he puts that learning to good use when we’re introduced into his life.

There was probably a time ‘way back, before our ancestors perfected the art of language, when we, too, communicated mostly with body language. But our world then, as theirs still is now, would have been quite small, and our need for communication quite basic. Not much has changed with horses over the millenia, however, and it’s safe to assume that horses everywhere communicate in the same manner. Interestingly, those of us who spend time with horses have intuitively picked up on their language without realizing it.

He “speaks” to us with his body language, and he expects us to “get it”. When we don’t he will sometimes add emphasis – flared nostrils, maybe, or a head nudge, or even a kick if just flattening his ears isn’t enough. And how quickly we learn from that sort of emphasis! It’s the same emphasis he uses when he’s communicating with another horse, and so it’s quite natural and not a big deal. Unfortunately, when that sort of emphasis happens many of us tend to blame the horse for an indiscretion instead of immediately realizing that he’s just “being a horse” and does not actually bear us any ill will. Usually, however, we can and do connect with his initial ear-flattened message – and so we learn, sometimes the hard way, a little more of his language.

But there is so much more to a horse’s language than flattened ears. It should be pointed out here that ear-pinning is just one of many examples of equine aggression behavior. We tend to think of aggression as meaning physical attack, but a physical attack and ear-pinning are both examples of aggression body language. We might define equine aggression body language as any physical attempt at control, whether it’s by flattened ear or sudden kick or anything in between, and much of it has counterparts in our own body language. That means that to a degree he and we already do speak the same language. You may become displeased with your horse for some reason, and you glare at him to “make” him behave as you want him to. Your “hard eyes” (your body language) mean the same to him as hard eyes from another horse, and he reacts accordingly. You sometimes use many facial muscles to emphasize your displeasure (clenched teeth, a big frown, hunched shoulders), he sees them all and interprets them accurately. And he does the same thing, actually; if he wants to emphasize his flattened ears, he may flare or purse his nostrils, raise his head up high to make himself appear more formidable, and even stamp his forefeet with great force; he’ll swish his tail, may turn his butt and stand with weight off of one hind leg so he can deliver a ritual kick – all signs to another horse that a big fight may be moments away if he doesn’t back off, and he uses it with us as well.

A much more common body language example of aggression is that of one horse moving another. We may notice it when it’s obvious – when accompanied by a nip on the rump, for example – but usually it’s so subtle that we rarely notice the body language that actually moves the “movee”. However, she reads it immediately, as do all other horses in the immediate area. The control of spacing between individuals in a herd is an important use of aggression body language, and it has many shadings. For example, at one extreme, when food is scarce each horse needs more space in order to find enough forage, and “back off” signs are the tools used to gain and retain it. At the other extreme, aggression is used continuously, in normal, non-stressed conditions – for example, the “intimate zone” between horses, up close and tight, is entered only by family and close friends, while others are warned off.

These are common examples of the body language of aggression — one of our horse’s two basic communication devices. Of course, herd members don’t spend their time in overtly aggressive behavior, and even when they use it, it is rarely violent. Although aggression body language is fundamental in a horse’s lifestyle, fortunately dominant horses – bullies — are relatively rare. It’s probably why herd members usually get along together so well.

His second basic communication device is cooperation. Cooperation is the most important characteristic of herd behavior – without it there would be no herd – and body language is the tool that makes it work. Cooperation between herd members implies mutual trust. Without trust a horse will see every new thing as a threat from which he must escape. Consider a grazing herd; each member knows the whereabouts and actions of every other member present, and through trust and body language, he knows that all is safe and content.

The body language of cooperation is often the antithesis of the body language of aggression; eyes are soft and ears are up, the head is down, grazing, amid a group of herdmates. Horses will lay on the ground for a brief nap in the presence of others; a “sentinel” horse will remain standing and watchful. These are body language messages of trust and acceptance. Two friends will groom each other, obviously in each other’s intimate zone. The foal will work its mouth in the presence of older, mature horses, an action sometimes called “snapping”, which is far from a threat, but rather a message that says, “I’m young, small and weak, and I mean you no harm. Be nice to me.”

We tend to think of body language as a system of clearly understood signals, and it is, but there is so much more to it than many of us realize. Because of the subtle nature of many body language signals, they occur without our being consciously aware of them. Yet we do pick up many of these tiny clues without realizing it – and so does your horse. You catch his eye moving to look at you while he’s facing off to the side, and you know that he’s paying attention; that’s body language. He sees and interprets a twitch of your eyebrow. Many a trick circus horse has been trained to “count” by tapping a forefoot just by reacting to eyebrow twitches.

While both horses and people communicate with their own species using body language, it might be assumed that there is a vast gulf between these two disciplines, but this is not the case. We think of ourselves as primarily verbal communicators, but there is surprising research that indicates that we communicate face-to-face verbally only one-third of the time – fully two-thirds of our intercommunication is via body language! Because of the similarities in body language used by horses and ourselves, how interesting it would be if, with some concentrated effort, we were able to bridge that gap somewhat and develop much greater mutual cooperation, understanding and empathy.

Equine Arthritis: Dealing with the Pain

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Written By Walt Friedrich

Ask anyone who suffers from arthritis what it’s like, and you’ll hear just one word repeated and repeated – pain. And you won’t have to look very far to find people to ask. In some cases, you don’t even need to ask – you can tell just by watching them move; they don’t like to because it hurts.

We’re not alone in coping with this painful monster – our horses, like humans, are quite prone to arthritis, and they hurt just as much as we do.

We hope medical science will soon be able to control it, even cure it, both horse and human, but until then, because it’s a chronic degenerative disease, the prognosis isn’t good. Once it’s in our joints, it’s there for keeps, and if left untreated, it just gets worse. So we compensate: we medicate to mitigate the symptoms. We avoid activities that we know will hurt.

Lucky us, humans can do that. Horses not so much. They rely upon us to see and recognize their symptoms, then do something about it to ease their pain, just as we do our own. Problem is, sometimes we don’t “get the message” when our horse hurts. But the clues are there, you can bet on it. We need to recognize what their body language is saying.

Fortunately, most of us can spot a horse that’s in obvious pain, though we may not be able to pinpoint exactly where it’s centered. Here are some of the general symptoms that tell us that our horse is hurting:

• An obvious limp • A listless, depressed attitude.

• Decreased appetite.

• Lies down more than usual

• Doesn’t move around as much as usual, less interested in playing • Separates himself from his herdmates

• When standing, eases the weight load on an involved leg by “pointing” a forefoot or “flexing” a hind foot to let the opposite leg take up the weight burden.

• When ridden, seems stiff, may refuse certain movements such as collection, jumps, certain turns and the like.

We get a break when examining specifically for arthritis: it is a disease that’s centered in the joints, which narrows down which areas we need to concentrate on. Here are some of the symptoms of arthritic pain:

• Joint swelling • Warmth around a joint

• Reduced ability to move the joint

• Stiffness, especially in the morning

• Misshapen joint

• When picking his feet, you notice less dirt, hay, manure packed in

When we do see the symptoms, we bring in the vet to do another evaluation, and if our suspicions are confirmed, our next thought is how do we get rid of the problem? Can’t we just take a pill?

Unfortunately, there is no silver bullet – not yet, anyway, though science is trying hard to develop one. As a chronic degenerative condition quite possibly stemming from an autoimmune problem, and at this point is incurable, we can’t get rid of arthritis by any simple medication.

Fortunately, we can deal with it and make our horse’s life immensely easier. There are effective lifestyle changes that can reduce pain, improve function, and arrest further joint damage. First, start a slimming down program if he’s overweight. That alone will greatly help joint pain in his legs and feet.

Controlled movement will help relieve stiffness and reduce pain and fatigue. Gentle daily exercise is excellent therapy, particularly important because affected joints need plenty movement to prevent permanent restriction of motion. Thirty minutes per day of steady walking, if his lameness permits, is usually enough. It will help to pick up an affected leg frequently and flex or extend the joints a dozen times or so. Free-range turnout is an excellent lifestyle for all horses, but note that it does not replace actual therapy.

Though inconclusive, some positive results have been reported from supplementation with bioflavonoids, and especially glucosamine and chondroitin sulfates. These two natural substances are readily available for purchase; they stimulate formation and repair of joint cartilage. In addition, add antioxidants such as vitamins C and E, plus a generous dosage of omega-3.

Applying a liniment such as Absorbine is quite helpful. It creates a mild inflammation that increases blood flow and eases the pain. Bandaging is also helpful because it holds in heat, but it’s mostly effective only on the fetlock (ankle). Other joints are better served using Neoprene wraps, but be careful if you use Neoprene over liniment – some liniments are irritating under Neoprene, and it is important to avoid irritating the skin. Read the liniment label for warnings. Massage the dosed area for ten or fifteen minutes after applying liniment and before bandaging.

Those sore joints will very much appreciate heat. Gentle heat is the magic touch for the pain of arthritis under everyday conditions. But his arthritis may flare up occasionally, and become much more painful. When it happens, ease up on his walking therapy, and use cold therapy instead of heat. You can use a garden hose (no nozzle), for example, and hose down a particularly sore knee. Temporary increases of antioxidants and glucosamine/chondroitin sulfate will bring some added relief. Please note that while bandaging will help control swelling, it also holds in heat, just the opposite of what you want during a flare-up, thus you may have to forego bandaging temporarily. Use discretion and never over-do.

During a flare-up, increase the dosage of bioflavonoids, vitamin E and especially vitamin C, and be sure glucosamine and chondroitin sulfates are dosed to full recommended levels, to help minimize further joint damage.

You can safely dose with Bute at flare-up time, but be careful. Only the worst cases require constant, repeated dosing, and that has some potentially serious side-effects. One is the suppression of an enzyme, resulting in the reduction of the stomach’s protection against ulcers. If the situation calls for frequent dosing of Bute, you can also supplement him with a half to a full cup of lecithin each day. Lecithin effectively protects the stomach wall from damage, is tasteless, and is relatively inexpensive. There are other products to control ulcer pain; discuss them with your vet.

Once a flare-up has eased, phase out the cold therapy and get back to hand-walking for brief periods several times a day. Long-term, exercise is of paramount importance.

If you shoe your horse, squaring the toes makes breakover easier and smoother, thus easier on arthritic joints, but be sure to keep the feet at their natural angle so you don’t complicate matters. Don’t use caulks, trailers or grabs on the shoe, and use shoe padding to raise the heel angles slightly.

Finally, consider his nutrition. Ideally, his primary feed should be low-sugar roughage, such as a grass hay like timothy, selected for proper mineral balance and sugar content. As previously suggested, supplement it with Vitamins C and E because of their excellent anti-oxidant qualities, and with high omega-3 fatty acids such as Omega Fields’ product, HorseShine. Round it off with a cup of canola oil per day.

Don’t expect a cure from these steps. There isn’t one. But you can most assuredly make life easier for him.

Equine Colic: Are You Prepared?

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Written By Dr. Kris Hiney

Most horse owners at one time or another have experienced that dreaded sight of finding their horse rolling or kicking at their belly in their pasture or stall.  After all, almost 1 million horses colic in the United States each year, or about 11 in every 100 horses. It really is not a matter of if, but when a horse in your care will colic.  But now is not the time to panic, but to act logically and calmly.  The keys?  Be prepared, and have a plan.  This month we will discuss what symptoms you may see, what to do, and how to create a firm plan of action.  Next month we will discuss several important strategies you may implement to decrease the likelihood of your ever needing this plan.

First of all, horses can colic for a variety of reasons. As colic just means a generic abdominal pain, any discomfort in the organs associated with the gastrointestinal tract can be described as colic.  Even other organs, such as the ovaries or uterus in mares, can causepain and thus may show symptoms of colic. So what may lead you to suspect your horse may be colicking?

My first and strongest recommendation is to know your horse. Every horse has individual quirks of behavior, appearance etc.  The key to successful outcomes in colic, or in many cases of disease or injury, is catching a change quickly.  Any change in a horse’s normal behavior or appearance should immediately trigger a thorough investigation of the horse by the owner or manager.  So what might the horse be doing differently? Colic symptoms can range from the subtle to the severe and downright alarming.  Typically the severity of the colic will mirror the severity of the symptoms, but that is not always true.  Individual horses have a greater or lesser degree of pain tolerance. It is important to know if your horse is the stoic individual that works through an injury, or the type that becomes hysterical if they stubbed their hoof on a ground pole!  Subtle signs include horses which are off feed or water, but may not yet be completely refusing to eat or drink.  A change in behavior, being more depressed, less active or having a duller appearance may be signs of colic. Horses which are restless, or perhaps laying down more than normal, or laying in an unusual position may be colicking.  Pay close attention to foals, as foals can quickly develop abdominal discomfort related to disease, diarrhea ulcers etc.  A foal lying on its back is certain to be experiencing some sort of abdominal pain.  As pain becomes more severe horses may continually look at their belly or flank, kick at their abdomen, repeatedly get up or lay down.  They may begin to roll or thrash violently and can even injure themselves.  In severe pain, horses may break out into a sweat or grind their teeth together.

Depending on the severity of the colic, your next step is to step in and gather some information.  Obviously, if your horse is in uncontrollable pain, call the veterinarian immediately.  Otherwise, if you can safely evaluate your horse, perform a physical exam on your horse.  That will help your veterinarian know how soon they may need to arrive.  Record your horse’s heart rate, respiration rate and temperature.  It is important that you practice these techniques before you need them!  A horse’s heart rate can be detected in a number of locations, near their eye, under their jaw, on their pastern etc.  Make sure that you have a working thermometer. Now is not the time to discover a dead battery in your thermometer.  Listen to your horse’s abdomen to hear if there is the normal gurgle of healthy gut movement.  An absence of sound indicated gut motility may have ceased.  If you horse is stalled, check his manure. Is there as much as there should be?  What consistency is it? Is it drier or harder than it should be?  How much feed has the horse eaten since his last feeding?  Is his water consumption normal?  Finally, check your horse’s gum color and capillary refill time.  Pale white or blueish gums may mean the horse is severely dehydrated, or may be going into shock.    This information may be critical in making decisions that may save your horse’s life.

Now that you have some basic information, call your veterinarian.  It is important to have the veterinarian’s phone number readily available. Think about all cases of emergencies.  What if your cell phone has no reception or has a dead battery? Does your veterinarian make emergency farm calls? Will they be able to get here quickly enough to help you?  Discuss these issues with your veterinarian before colic strikes. They may offer some helpful advice on other colleagues they may trust when they may not be able to make the call.  Therefore you may want to post several numbers of veterinarians near your horse.
You also need to do some hard thinking about the financial reality of colic cases. Some colics can only be resolved surgically.  Are you prepared for this?  Can you financially afford colic surgery?  Realize that is possible for colic surgeries to cost nearly $10,000.  Looking into an insurance plan for your horse can help cover major medical costs.  Do your research and see which plan may be best for you and your horses.  You may also need to at least consider that the outcome of surgery may not be positive.  Discussing these scenarios with family and your veterinarian before your horseever colics is critical.    It will make this emergency scenario much easier on you and allow you to make decisions more quickly.

If you have made the decision that surgery is a viable option for you, add more details to your plan.  Do you have ready access to a truck and trailer? If you do not own your own, you need to have numbers of individuals absolutely willing to help, and located nearby, close at hand. The last thing you want at this point in time, is knowing your horse needs to get to a clinic, but you can’t find transportation.  Finally, know where the nearest veterinary hospital with surgical capabilities is located.  How long will it take to get the horse there?  This may affect your decision on when to load your horse on the trailer. Should you wait for your veterinarian to arrive at the farm, or should the horse immediately go to the clinic. Know where the clinic is located.  Now is not the time to be looking for directions or get lost in the middle of the night.  Practice!  The more that you have mentally and physically prepared yourself for these emergencies, the better the outcome for both you and your horse!
 

Pasture Grasses and Grazing

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Written By Dr. Kris Hiney

This month we will review research concerning pastures and foraging behaviors in horses. Most horsemen would agree that horses grazing at pasture represent the most natural way to feed a horse.  Certainly it represents the most economical and the least labor intensive method of feeding.  However, many owners have questions related to what or how much a horse’s is consuming when its primary source of feed is pasture grass.

This ambiguity of how much grass a horse may consume makes selecting additional concentrates or supplements more of a challenge.  In addition, many horses clearly volunteer to consume pasture grass well over their nutritional needs making regulation of body condition score very difficult.   The range of dry matter intake of horses on pasture has been reported to be as wide as 1.5 to 3.1% of their body weight in a 24 hour period. Usually young horses and lactating mares will be on the upper range of intake which would make sense due to their nutritional demands.   Mature horses are reported to typically consume 2-2.5% of their body weight in dry matter.  However, it does appear that many of our equine friends have failed to adhere to book values when given the opportunity.  A recent study looking at weight gain in pastured ponies found that on average the ponies consumed 3.8% of their body weight in dry matter, with ranges of 2.9 to 4.9%.  Others have also reported horses consuming as much as 5% of their body weight in dry matter! It is rather easy to see why horses can quite easily gain weight on pasture.

But what about horses which are only turned out for part of the day in an attempt to control feed intake? Is this an effective technique or do they simply manage to eat faster in their allotted grazing time?  In a study which attempted to determine how much a horse can consume in an 8 hour period, horses were individually assigned to small paddocks, allowed to graze for four hours, then switched to a new paddock for an additional 4 hours. The small paddocks were then harvested to determine how much the horses consumed in the given time period. In this experiment horses were able to consume 1.3% of their body weight within an 8 hour period.  In addition, their consumption rate was twice as high in the initial four hours the horses were allowed access to grazing. Therefore the horses were able to consume almost 1% of their body weight in just four hours!  Thus even limited grazing can easily result in weight gain.  From this data the authors concluded that for these particular grazing horses, only 9 hours of grazing was necessary to meet their energy needs.


While we know that good quality pasture can easily meet a horse’s maintenance requirements, does it provide additional benefits to the horse?  In a study designed to look at the effectiveness of pasture turnout in maintaining fitness, horses which has been ridden 1-2 hours per week, 5 days per week for 12 weeks were then stalled, continued to be ridden or were turned out in a large pasture.  After a 14 week period, all horses participated in a standard exercise test.  This proved that the horses allowed free access to wander through a relatively large pasture maintained their fitness compared even to the horses ridden 5 days per week.  Thus pasture turnout seems to be a reasonable solution during down time when the horse is not ridden for maintaining fitness. The pastured horses in this study traveled on average 10 km a day compared to 5 km per day in the horses which were ridden.  This study again lends support to the value of pasture turnout.

So what if we want the fitness benefit of pasture turnout without the obesity inducing over consumption?   Often the traditional answer has been to employ a grazing muzzle. In a study looking at intake rates in ponies wearing muzzles compared to their non-muzzled counterparts, muzzling resulted in an 83% decrease in overall intake. However, in just three hours, the non-muzzled ponies were able to consume 0.8% of their body weight in dry matter.  This is quite similar to the observations in the previous studies.  In addition, the same team of researchers found that the ponies “grew wise” to their limited access to grass and learned to increase their consumption rates during their restricted period.  Therefore limited time on pasture may not be as effective for foxy ponies once they learn what you are up to!  So what is our take home message?  Allowing horse’s time to graze is very beneficial, not only for their mental health, but also for their physical health.  However, in order to control intake and thus body condition score in our enthusiastic eaters, we made need to employ additional measures such as limited turnout or grazing muzzles.

Equine Research: Protein

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Written By Dr. Kristina Hiney

This month I will begin a new series which tries to summarize some of the new information which has been gathered in equine nutrition.  I will be grouping similar topics together and trying to summarize how this information might be relevant to you and your horse.  We will discuss if this new information means you should change what you have been doing, or you can feel reassured that you are right on track!  And remember not all information may be relevant for your horse.  There is no need to feed your mature gelding who is trail ridden on the weekend like an endurance horse preparing for a 100 mile ride!

This month we will focus on some new information on protein nutrition in the horse.  Certainly this is the time of year when many of us are busy procuring our hay supplies for the upcoming year.  Often we want the very best for our horses, and typically look for high quality alfalfa hays.  But is that necessary, especially in a year where the weather does not cooperate and hay selection may be more limited?  In a study using mature idle geldings, the digestibility and usefulness of protein from a variety of hays was tested.   Horses were fed diets of either  mixed grass hay alone, the mixed hay with increasing amounts of oats, or alfalfa hay that was either early bloom, mid bloom or late bloom.  As the maturity of alfalfa hay increases, typically its protein content decreases.   Therefore, many horsemen prefer earlier bloom alfalfa.  But is this necessary? In this particular study the horses were also fed at just 1.6% of their body weight as fed, which is typically a little lower than most people feed.  Thus these horses might have been fed at a lower rate than the average horseman would feed.    As expected, the protein intake of the horses increased as they were fed the alfalfa hay, with increased protein intake the earlier the stage of maturity. The digestibility of the protein in the diet also increased when fed straight alfalfa compared with the mixed hay, and digestibility was greater with less mature alfalfa.  That does reconfirm our knowledge that forages of later maturity are indeed less digestible.  However, the nitrogen retention between the groups of horses was not different.  Nitrogen retention refers to how much nitrogen remains in the horse’s body.  So if the horse’s nitrogen intake (which is reflective of protein intake) was higher, but the nitrogen did not remain in the horse’s body, where did it go?  The extra nitrogen was actually excreted in the urine.  You may remember from our earlier series on protein nutrition that excess protein consumed cannot be stored in the horse’s body. Instead, the nitrogen is removed from the amino acid, and the remainder of it can be used for energy or stored as fat.  Overall, for mature idle horses, there is no need to feed these higher “octane” hays, as it all that extra protein just ended up back on the ground!  There was no value to the horse in these high protein hays.

However, what if you are not feeding a mature, idle horse, but instead are feeding mares and foals?  Their protein requirements are undoubtedly quite higher.  But it is not just protein quantity we must consider, but also the amino acid profile of the diet.  You may remember from previous articles that equine nutritionists have only described the requirements for lysine in the horse.  This is in stark contrast to other species in which the complete amino acid requirements have been well defined for  both growth and lactation. In other species, lysine is also known to be the first limiting amino acid, followed by threonine and methionine.   It is presumed that this may be true in horses as well.   In a study looking at pregnant mares, their subsequent foals and the mare’s themselves during lactation, researchers posed the question if plasma amino acid concentrations would differ after eating.   Theoretically, plasma amino acids which increase the least after eating immediately following a fast indicates the limiting amino acids.  In the weanlings, the amino acids which increased the least were methionine and lysine, for lactating mares it was methionine and for pregnant mares on this particular diet the amino acid which increased the least was leucine, one of the branched chain amino acids.  This study supports the idea that methionine may be the second limiting amino acid for nursing mares and weanlings, but leucine may also need to be considered.  However, this study did not provide information on how much of these amino acids may actually be needed in the diet, but stresses the need for additional studies.

The final study we will look at did try and examine the question of methionine needs in growing horses.   In a study which looked at the growth rate and plasma metabolites of weanling horses fed differing amounts of methionine, growth rate did not change with addition of methionine. However, weanlings were only fed the diet for 56 d which way not have been long enough to observe differences.    Addition of methionine did result in a decrease in plasma urea nitrogen.  But what exactly does that mean?   Remember that any extra amino acids must be catabolized and the amine group is removed as urea. The urea is synthesized in the liver, but excreted by the kidney.  Urea circulates though the blood prior to its removal.  An increase in plasma urea N indicates an increase in amino acid catabolism, which takes place if protein synthesis is limited by the availability of amino acids.  If we assume that an increase in methionine in the diet allowed more protein synthesis to occur, this would result in more N retention, and less amino acid catabolism.  In this study, the authors did not observe a linear decrease in plasma urea nitrogen as  methionine was increased beyond 0 .2% of the concentrate. In this example, the weanlings were fed at a rate of 1.25% of their body weight in concentrate, or about 8.4 g of methionine.  You may have noticed that many feed companies now include the levels of methionine in their product.  Using this study as an indicator of methionine requirements, at least for weanling horses would indicate that methionine should at least be at the level of .2% of the concentrate if fed in comparable amounts. If less concentrate is fed, than the concentration of methionine should be higher.

To summarize what we can take from these three studies, we have reaffirmed that mature idle horses don’t really need high protein hays. While their protein may be more digestible, those amino acids remain largely wasted.  For horses with higher protein needs, it may be time for us to turn our attention to more than just protein quantity, but quality as well.  Hopefully soon we will have better knowledge on exact amino acid requirements, but at least we are now somewhat closer to knowing about methionine!

Keys to Preventing Laminitis

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Written By Dr. Kris Hiney

In previous articles we have discussed some of the key strategies in preventing laminitis in the equine.  Many of these have centered on grazing strategies which limit the horse’s access to pastures high in fructan content.  Remember that fructans are carbohydrates which are enzymatically unable to be digested in the small intestine of the horse.  These fructans pass into the hindgut of the horse where they are fermented by the microbial population, specifically gram positive bacteria. The production of certain organic acids and amines enhance the permeability of the gut wall allowing these and other endotoxins to enter the bloodstream of the horse and ultimately effect  the circulation to the digit.  However, it is not practical to simply right off all horses’ ability to graze.  Rather, we should try and identify those individuals which may have a susceptibility to fructan content in the grass.  With this month’s article, we will try to identify which individuals may be at risk, and other strategies that may be employed to reduce your horse’s risk.

While the outward appearance of your horse may give you an indication to whether they are susceptible to laminitis (See Carbohydrates III: Metabolic Syndrome), there may be more to it than just which horses are overweight.  There certainly appears to be a genetic link to laminitis, with pony breeds leading the list of susceptible horses.  Their comparatively thrifty genotype may make their utilization of carbohydrates and insulin sensitivity differ from breeds which typically do not possess these characteristics. For example, thoroughbreds, which typically have the reputation for being “harder keepers” do not experience the same rate of laminitis.  However, the lifestyle and management of thoroughbreds may differ significantly enough to partially explain the decreased incidence of laminitis.  Even within ponies, there does appear to be a decided link to genetics.  In a study examining the pedigrees of an inbred herd of ponies, 37% of these ponies had experienced laminitic episodes.  Of those, half had at least one parent which had also experienced laminitis.  Even in controlled research trials which attempt to examine the effects of various carbohydrate loads on horses, wide variability exists between individuals. This leads to the supposition that individual variation, thus genetics, is at play.  Thus, if you aware of your horse’s pedigree and know of relatives which have experienced laminitis, you might want to manage your own horse more carefully.  Perhaps some day the genes which make a horse more susceptible to laminitis will be identified, and we can use genetic tests in developing management protocols.

As mentioned previously, development of obesity and insulin resistance certainly predisposes the horse to laminitis.  One theory behind the development of laminitis in the insulin resistant horse is the glucose deprivation model.  When a horse becomes insulin resistant, more and more insulin release is needed to elicit a normal tissue response.  In essence, the tissues become “desensitized” to insulin.  One of the key roles of insulin in the body is to allow cellular uptake of glucose.  Due to the polarity of glucose, it cannot freely enter the cell without the presence of specialized protein transporters. Glut 4 is a protein transporter which is located internally in the cell until insulin binds to the cell membrane.  Binding of insulin to the receptor causes a cascade of intracellular reactions to occur and initiates the translocation of Glut-4 to the cell membrane.  The insulin insensitivity may result in Glut 4 no longer moving to the cellular membrane, and the inability of glucose to enter into the lamellar tissue of the foot, thereby starving it of glucose.  A recent study looked at the presence of different glucose transporters  found in skeletal muscle, the coronary band and lamellar tissue.  Glut-4 is the insulin dependent transporter found primarily within muscle, while Glut 1 is found in other tissues which have non-insulin dependent uptake of glucose, such as the brain.  While Glut 4 was heavily expressed in skeletal muscle, only Glut 1 was found within hoof tissues of both normal and insulin resistant ponies.    Therefore, glucose uptake in the hoof is thought to be insulin independent  and glucose deprivation within the hoof is unlikely to be the cause behind laminitis.  However, in a subsequent study, laminitis was induced in normal healthy ponies using a hyperinsulinemia-euglycemia clamp technique.   In this model, insulin is infused into the ponies at a constant rate, while glucose is infused at a sufficient rate to maintain euglycemia, or normal blood glucose levels.   Therefore, it is not an absence of glucose which causes laminitis, but perhaps the sustained levels of insulin or other hormones which causes this disorder.  This would certainly support the observation of the increased laminitis risk to the insulin resistant horse which suffers from hyperinsulinemia.

If owners wish to try and avoid the development of insulin resistance, the diet the horse receives may be critical.  Diets which avoid high amounts of sugars and starches, and have a low glycemic response, result in less insulin release.  For horses which still need a significant amount of calories, diets which are fat and fiber based and properly formulated, rather than those which provide a higher glucose or insulinemic response, may prevent the development of insulin resistance.   Certainly just monitoring body condition in the horse may be the easiest way to avoid insulin resistance.  Although if you ask any horse owner if that is easy you may get a different response!  In addition, horses which receive regular exercise seem to be fairly protective against laminitis.  However, it is difficult to know whether the exercise regimen aids in increasing insulin sensitivity, or is simply protective against obesity.

Many horse owners wonder if there is a magic pill or supplement that they can provide their horse in order to prevent laminitis.   One approach is to reduce the gram positive, lactate producing bacteria which prefer to ferment sugars and fructans.  Antibiotics are commonly used in the livestock industry in order to promote growth by shifting the microbial population within the gut. Some antibiotics select against gram positive bacteria, thus have been studied in the horse as a way to prevent laminitis.  While this may work, the use of anti-biotics in livestock for growth promotion has been banned in the Europe Union over concerns of anti-biotic resistance.  Similarly many in the United States have followed suit, searching for other ways to influence growth and increase immune status.  The use of probiotics and prebiotics may influence the gut microflora in favor of less potentially problem causing bacteria.  Ironically enough, short chain fructo-oligosaccharides have been demonstrated to improve insulin sensitivity, if not glucose levels, in obese horses.   However, none of these methods have been proven to prevent laminitis.  I would caution individuals to monitor diet, grazing patterns, and body condition first, before relying on supplements to prevent laminitis.

Obesity in Horses: II, Balancing Diet and Exercise

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Written By Dr. Kris Hiney

In Part I of this series, we talked not only about the difficulty in removing extra pounds from our equine companions, but also the health benefits that our horse will gain from doing so. Our strategies included seeking a more mature grass hay with a lower caloric density and reducing the amount of forage offered to the horse.   The horse will probably need to be confined to a dry lot, but fed in a way to minimize boredom related to reduced  feeding time. This month’s article will look more closely at the diet of our horse, to ensure that we are reducing the calories the horse receives, but are still feeding a balanced diet that provides sufficient amounts of our other nutrients.
We will continue to use the example of our 1300 lb horse who was at a body condition score of 8 and a goal weight of 1165 lbs. The maintenance requirement for the 1165 lb horse was 17.7 Mcal per day. We decided to feed the horse at a rate of 1.5% of its target weight in order to achieve the desired weight loss. That would mean our horse would consume 17.5 lbs of feed per day. Now, because we specifically chose a lower calorie hay which is more mature, it probably is lower in other nutrients as well. In order to ensure that your horse’s amino acids, vitamin and mineral needs are met, one should look for a low calorie supplement. Fortunately many reputable feed companies produce feeds that are designed for the easy keeper. Typically these feeds will be much higher in crude protein, minerals and vitamins and are designed so that you only need to feed one to two pounds per day. This ensures that your horse will not suffer from deficiencies while we achieve the desired weight loss.
Additionally, we can accelerate the horse’s weight loss by instituting a regular exercise program. Now, assuming our horse was at a body condition score of 8, it probably wasn’t on a consistent exercise program earlier. The key in implementing an appropriate exercise program is to realize that the horse is relatively unfit and we should begin exercise carefully. Ideally the horse should be ridden or worked five to six days per week.   If this is not possible, try to institute an exercise program at least every other day. Begin with intermittent periods of walking and trotting, and slowly increase the duration of the trotting periods. You should notice that the horse is able to recover its heart rate and respiration rate more quickly during the walking recovery periods as it becomes more fit. Then you can increase the intensity of its exercise program.
Now let’s take a look at how much exercise your horse needs for increased energy expenditure. For every 45 minutes the horse spends walking per day, it will expend an additional one Mcal/d of net energy.  But what exactly is net energy? To this point in time, we have always discussed the energy needs of the horse in terms of dietary energy or DE. Dietary energy refers to the energy available in the feed once the digestibility of the feed is taken into account. When we determine how much to feed our horse, it is always based on the DE concentration of the diet compared to the horse’s DE requirements. Net energy is more specific about the flow of energy through the horse’s body. Net energy refers to the amount of energy needed to support exercise, growth, lactation, etc. after other energy losses to the horse have been accounted for. These other energy losses include the energy lost from gas production, urine, the work of digestion and the heat lost from the digestion and fermentation of the feed. The energy that is left over after all of these losses is what is available for the animal to use for other purposes.
The efficiency of conversion of dietary energy to net energy of a horse in light-to-moderate exercise is only about 40%. Therefore, if the horse expends 1 Mcal of net energy, he actually used 2.5 Mcal of DE.  Even regular trail riding will greatly help the horse with our weight loss goals, but increasing the exercise intensity will increase the calorie expenditure even more. If we use the horse’s heart rate as a guide, we can determine how much exercise they need to perform to represent significant calorie expenditure. Let’s say we would like to increase our horse’s energy expenditure to 20% over his maintenance energy requirements. Our goal for our original horse, then, is to use an additional 3.5 Mcal every day.   Our horse’s typical heart rate when he is walking is usually around 60 bpm while trotting will elevate the horse’s heart rate to around 90 bpm. This relates to 24 kcal/min and 56 kcal/min of net energy respectively for walking and trotting.    If we convert that to Mcal of DE, our horse is consuming .06 Mcal /min or .14 Mcal of DE/min. To achieve an energy expenditure of 3.5 Mcal, that would mean we would walk our horse for almost an hour a day, or about a half hour of trotting.  However, these are heart rates of horses which already are fit. For the obese horses we are discussing, the heart rates are usually higher, thus less time will need to be devoted initially to exercising these guys. Good news for them! Heart rates for an unfit horse trotting have been recorded at 120 to 140 bpm! This would correspond to about 0.25 Mcal of DE per minute. Thus only about 15 minutes per day would achieve our increase in energy expenditure of 20%. Remember, this would be 15 minutes total of trotting with intervals of walking. As the horse begins to become more fit and its heart rate lowers, he will tolerate more exercise and will need to increase the amount of time he works to continue using the same amount of calories.
Alternatively, once our horse is fit, we can also add bouts of cantering or loping to his exercise program.   A horse which is cantering typically has a heart rate between 110 and 130 beats per minute and utilizes about .25 Mcal of DE/min. If we add 10-20 minutes of cantering to our exercise program, the duration the horse needs to be ridden to achieve our target energy expenditure would be about 45 minutes per day, which is probably more realistic for most horse owners. This would include a mix of walking, trotting and loping. Combining this regular exercise program with our restricted diet will help your horse add years to his life.
Good luck with your weight loss goals.

Feeding Horses for the Prevention and Management of Laminitis

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Written By Dr. Kris Hiney

Nothing is more devastating to the horse owner than to have a treasured partner be afflicted by the painful, crippling disease of laminitis. Laminitis can be a debilitating disease that may ultimately result in the death of the horse or humane euthanization. Unfortunately there are so many factors that can manifest in development of this syndrome that it can be difficult to sort through.
To understand the development of laminitis one should really understand the physiology of the equine foot. Essentially the hard keratinized tissue which forms the hoof wall is held to the soft tissue by the interdigitation between the sensitive and insensitive laminae. The insensitive laminae (seen here in Figure 1) is formed in vertical sheets on the inside of the hoof wall. 
Figure 1. An interior view of a horse’s hoof with the soft tissues removed. 1b. A schematic of the vertical lines of insensitive laminae lining the interior of the horse’s foot.
Connecting to the insensitive laminae is the sensitive laminae, which is living tissue requiring an adequate blood supply of oxygen and nutrients to survive. When an alteration of blood flow or a vascular insult occurs inflammation or even death of the sensitive laminae can occur. The sensitive laminae ultimately stabilize the internal structures of the horse’s hoof, including the third phalanx (or coffin bone). When this stable connection is lost, the pull of the deep digital flexor tendon on the base of PIII rotates it out of place. This condition is referred to as chronic laminitis or founder.
Figure 2. The sensitive laminae which connect the hoof wall to the horse’s foot.

Figure 3. A foundered hoof where PIII has rotated out of place due to the pull of the deep digital flexor tendon.
 
There are many reasons why blood flow can be disrupted to the equine digit. Laminits is often a systemic disease which is only visualized in the foot. While digestive issues lead the list of causes of laminitis there are other physical insults which can occur as well. When procuring wood shavings from a reputable dealer, care should be taken never to include those of the black walnut tree. These shavings contain the chemical juglone, actually a toxin which can kill other plants in the black walnut environment. Other physical causes are concussive trauma, from being ridden on hard surfaces resulting in decreased blood flow to the foot, and excessive loading (i.e., one limb is severely lame resulting in extra loading to the sound limb). Endotoxemia, such as what might be seen in a mare with a retained placenta, may also result in the development of laminitis.
 Nutritionally, a whole series of gastric insults can alter blood flow to the foot.  These include a carbohydrate overload (the classic example of the horse breaking into the feed bin) which leads to an alteration of fermentation in the hindgut.  In order to prevent starch from escaping enzymatic digestion in the small intestine and escaping to the hind gut, it is recommended to avoid a starch intake of more than 2-4 g/kg of body weight per meal. Therefore, a 500 kg horse should receive no more than 1-2 kg of starch per meal.  Pasture grasses have also long been known to precipitate bouts of founder, but typically only in susceptible populations. Ponies, and horses with thrifty genotypes are the most likely to suffer from pasture-associated laminitis. It is believed to be caused by a high level of fructans, although the quantity of fructans required to cause laminitis is unknown. Fructan content is known to vary with the time of year, with a higher content seen in the spring, when most pasture-associated laminitis occurs. Horses which are susceptible to pasture-associated laminitis should also limit their intake of pasture grass in the afternoon, when photosynthesis throughout the day has resulted in a higher level of fructans in the plant. The levels of water soluble carbohydrate gradually decline through the night, making grazing in the morning relatively safer. As the majority of horses which develop laminitis due so on pasture, rather than through the owner feeding excessive concentrates, at least some thought or caution should be used when grazing horses. Ideally horses should be introduced gradually to consuming fresh grass, and susceptible horses’ grazing should be limited to when fructan concentrations are at their minimum.
If a horse does develop chronic laminitis, unfortunately there is little the owner may do nutritionally to manage the horse. Obviously exposure to pasture grasses at peak times of fructan concentration should be avoided. Also, the horse should be managed to lower body weight to decrease the mechanical load on the laminae. Low energy forage should be the primary feed for the foundered horse. However, because low energy forages will typically be deficient in protein, minerals and vitamins, it is important to ensure that the horse is supplemented with a low energy concentrate to make up for dietary insufficiencies. As these horses are often in a great deal of pain, NSAID administration may often be needed, but can also contribute to gastrointestinal upsets. Alternatives to NSAIDS, such as Omega-3 fatty acid supplementation, may help to alleviate some discomfort, without the negative side effects.
Overall, close attention to the diet of the horse, avoiding GI disturbances or causing fluctuations within the hind gut, and limiting grass intake during periods of time where fructan concentrations can be high, will hopefully prevent the horse from ever experiencing this deadly disease.

Feeding Horses with Respiratory Allergies

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Written By Dr. Kris Hiney

Similar to people, horses can develop allergies to environmental contaminants that lead to asthma-like symptoms. In the equine world, this syndrome is referred to as recurrent airway obstruction (RAO). It was previously referred to as chronic obstructive pulmonary disease or (COPD) but due to dissimilarities with the syndrome observed in humans, RAO is now the preferred term. When some horses are exposed to dusts and molds, they develop allergies.  Why some horses do and others do not develop allergies is unknown. There is some evidence that this disease may be genetic. Horses born to affected parents are three times more likely to develop RAO than horses born to non-affected parents. Therefore, if you know your horse is predisposed to RAO, it is even more important to identify the symptoms and to properly manage its environment.
Identifying RAO
When the horse is exposed to an allergen, the body responds by increasing inflammation through the bronchioles coupled with bronchoconstriction.  The lungs increase in mucus production which the horse may not be able to clear easily. Frequently nasal discharge is seen, along with coughing, an increase in lung sounds and more distress during breathing. Lung sounds are typically heard with expiration, or the horse will “wheeze” when breathing out. Continual exposure to allergens may lead to fibrotic changes within the lungs. This will result in a horse which cannot take in oxygen to the same extent as an unaffected horse. You may notice that the horse has an increase in respiration rate over what is normally experienced during exercise, or he may become more exercise intolerant or fatigue easier. Horses with this syndrome which have had it more severely or more chronically may even develop a “heave line”. This is due to the hypertrophy of the abdominal muscles which must be used to assist the animal in breathing, rather than just solely using their diaphragm.
Management of the RAO horse 
As pollen and mold counts increase in the environment, horses with RAO will experience more symptoms or episodes of RAO. Often barns and stables are not designed with proper ventilation in mind. This contributes to a continual exposure of the horse’s respiratory system to particulate matter. Hay and straw bedding ideally should always be stored in a separate building from where horses are housed, and certainly not overhead. Additionally, the stalling area should be separate from the riding arena. All the dust that is kicked up while horses are exercising can greatly exacerbate the problem. Ever think about how much dust is stirred up into the air while the barn aisles are being swept? Ideally all of this dust exposure should be minimized and RAO affected horses removed from the barn whenever dust is stirred up. One of the best changes to management practices of the RAO horse is simply to house them outdoors. Often an improvement in airway function is seen within days.
While horses stabled inside are clearly more likely to be exposed to particulate matter, horses on pasture during the summer can also have trouble. This even has its own nomenclature,  summer pasture associated obstructive pulmonary disease or SPAOPD. Horses with this syndrome should be kept off pasture during the summer months, but can be housed outdoors during the rest of the year. If horses must be housed inside, whether they are SPAOPD or perhaps competitive horses that must be stalled, it is imperative that the environment is as dust free as possible. Straw bedding may not be a great choice for RAO horses but shavings can also contain molds similar to those in hay and straw. High quality straw may actually be lower in spore count that some shavings. Alternative beddings may yield the best results such as cardboard or newspaper pellets. If straw or shavings are used, remove any RAO affected horses while bedding is introduced into the stalling area. Essentially, let the dust settle before the horse is put back into the stall!
Feeding management
Ideally the RAO horse should graze fresh pastures as much as possible, but obviously this is not always possible.  One of the most immediate dietary changes for the affected horse is to absolutely eliminate any moldy hay or straw that may be in the horse’s environment. While moldy hay should never be fed to horses, it is more critical with RAO horses.   One of the difficulties in finding suitable hays for RAO horses is that humans may not always be able to detect the presence of mold if it is not obvious. Try to find hay sources from a knowledgeable producer who bales high quality hay. The type of fungus which produces the most damaging fungal spores prefers relatively hot temperatures. This would be seen in poorly cured hay, or hay that is baled at too high of a moisture content. The heating which occurs during spoilage is a haven for these fungi.  Round bales may not be an ideal choice, unless they are stored completely inside and are never subject to any sort of spoilage. Additionally, round bales encourage the horse to almost bury their head within the bale, making the immediate breathing area of the horse very dusty. Completely pelleted diets might be a good choice for these horses at it greatly eliminates the dust exposure to the horse while feeding. The quality of the pellet is also critical. Uncoated pellets may break down more easily and have a substantial dust component. Hay cubes and haylage are also alternative feeding strategies.   Moistening the feed can also help in dust suppression prior to feeding. Hay only needs to be soaked for 30 minutes to achieve optimal dust suppression. Beyond that time no additional benefits are seen. However, the down side to soaking the hay is that some of the nutrients are leached out into the water, including P, K, Mg and Cu.
Beyond eliminating dust and molds other dietary therapy may be aid the RAO horse. Supplementing RAO horses with additional anti-oxidants in the diet may be helpful. There is an increase in free radical formation or reactive oxygen species (ROS) in horses with lung inflammation. In fact, the increase in RAO may increase the upregulation of genes which produce inflammatory factors such as interleukins. Horses with RAO given a supplement of vitamin C and E plus Se resulted in less airway inflammation and an increase in exercise tolerance. Other natural sources of anti-oxidants such as sorghum and omega 3 fatty acids have not yet been studied for their effectiveness in RAO horses.   Additionally, due to the increased energy requirement just to breath, RAO horses are often underweight. The sustained stress to the horse’s system may also contribute to this weight loss. You may need to find a feed with an increase in energy density, such as a fat added feed to help maintain its body weight as well as additional anti-oxidants.
If one follows these management guidelines carefully, RAO horses may be symptom free for years to come.   While pasture is ideal for RAO horses, performance horses which need to be stalled can be kept healthy with a rigorous adherence to maintaining a dust and mold free environment and proper dietary management.

Feeding for Digestive Health

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Written By Dr. Kris Hiney 

The digestive tract of our equine companions is typically the system which most often goes awry. Colic and other digestive related upsets are the leading cause of death in the equine, but luckily can largely be avoided with careful management. If we understand the normal digestive physiology of the horse, we can avoid errors in our feeding program.
One of the most important features of a good feeding program for horses is providing an adequate amount of good quality forage for our horses. If we think about how a horses’ digestive system is designed to function, the relatively small stomach of the horse is designed to ingest small amounts of material throughout the day. This provides a constant influx of roughage to the hindgut, where it undergoes microbial fermentation. This is certainly the most healthy system and natural way of feeding horses. However, most horses managed in current stabling scenarios are meal fed, typically twice per day. While perhaps unavoidable, we try to offset this somewhat unnatural system by ensuring the horse receives enough forage for both its digestive health, and mental health as well.  Typically, horses will consume 2% of their body weight per day in dry matter. Most hays are usually around 85% dry matter (meaning they still retain 15% moisture after drying). For a thousand pound horse, that means that we should offer at least 23 to 24 lbs of hay per day. See calculations below:
1000 lbs x .02 = 20 lbs of DM
20 lbs DM/.85 = 23.5 lbs of hay as fed (or what you would actually weigh out)
Beyond just the shear amount of hay we offer, we should also think about the time the horse spends consuming that feed. If we again think about the natural feeding behavior of the horse, they eat for about 18 hours a day, continually traveling and searching for the most tender, nutritive grasses. When horses are deprived of feed, the pH of their stomach begins to drop, making them more susceptible to ulcers. In fact, a drop in pH of the stomach begins within 5-6 hours after the horse ceases eating. At 10 hours post feeding, the horse’s stomach is completely empty.
Beyond the obvious health risks this poses, the horse is unable to perform its natural foraging behavior. This encourages the development of stable vices such as cribbing, wood chewing, etc. which can be further detrimental for the horse’s health.
Therefore, our feedings should be spread out through the day to account for this.  Alternatively, we can offer more hay to our horse then the previously discussed 2% to allow them to participate in their normal desire to pick through their feed to select the most desirable parts. Realize this may increase the amount of hay wastage and economic loss. In addition, offering more hay can result in horses gaining more weight than desired if not offset by adequate exercise. If this is the case, look for hays that are lower in digestible energy (typically grass hays). However, this does not mean a decrease in quality such as the inclusion of dust, molds, weeds, etc.
In addition, the regular intake of roughage allows for a more stable population of bacteria in the gut. When the diet of the horse is radically altered, a shift in population of bacteria in the gut occurs, responding to the new environment supplied to the bacterial. This sudden shift in bacteria can result in digestive upsets, as well as development of laminitis. Therefore, any feed changes should occur gradually.  This includes the new pasture growing in the spring. Horses which are kept stalled or in dry lots should not be suddenly turned out into rapidly growing pastures in the spring. Ideally they should be introduced gradually, increasing the duration the horse has access to the pasture.
While maximizing forage intake is certainly ideal, what if you have a horse which cannot meet its energy needs through forage alone? Such horses usually fall into our moderate to heavy work category, or our lactating mares and growing babies. These horses then need to have a more calorically dense energy source, such as concentrate (or grain). When we feed a large amount of concentrate to a horse, the pH of the digestive system also changes, which may be detrimental. To avoid this, it is advisable to feed no more than .4% of the horse’s body weight in non-structural carbohydrate at any one meal. Our traditional grains such as corn and oats are abundant in nonstructural carbohydrates, which provide an excellent source of energy, but more care should be taken in feeding substantial quantities. Alternatively, we can provide feeds which are higher in rapidly digestible fibers, such as beet pulp, citrus pulp and rice bran. Many horse feeds now contain these ingredients as energy sources. In addition, rice bran is high in fat, which provides an extra boost of calories. Fat is 2.25X more calorically dense than carbohydrates, and provides a great way to increase calorie consumption with a lower risk of digestive upsets. Fat added to feeds may also dampen the increase in blood glucose seen after feeding concentrates. Finally, a horse will need less feed by weight when consuming a fat-added feed than a traditional concentrate.
One of the final considerations to maintaining a healthy digestive system of the horse is to ensure it receives adequate water every day. Horses on harvested feeds need adequate water intake to maintain the fluid environment of their digestive tract. If forage is higher in fiber and less digestible, it is imperative that the horse receives enough water to keep digesta moving normally through the tract. Most horses consume at least ten gallons of water a day. It is ideal to provide more water than the horse consumes (i.e., the bucket should not be empty before refilling).  Also be sure that, in the winter, the horse has access to water. In cold environments rapidly freezing water may lower a horse’s overall intake and make him at risk for impaction colic. Using bucket or tank heaters or a more frequent watering schedule will ensure that everything keeps moving regularly through your horse!
Following these simple guidelines for feeding will help avoid costly veterinarian bills and keep your horse healthy, both mentally and physically.