Feed Your Horse Like A Horse

Excerpt from Chapter 1 – Ground Rules for Feeding a Horse

Understanding the Digestive Tract of a Horse

The digestive tract of a horse is different from that of most other animals. Humans, cats, dogs, pigs, and other predators are able to digest meat and plant foods, but are not able to digest the fiber found in plants. This is because the digestive system does not produce the enzymes necessary to break down fiber molecules into small pieces. The result? The fiber leaves the body undigested as fecal waste.

But many animals have a four-compartment stomach that includes a “fermentation vat” where billions of beneficial bacteria live. These bacterial flora are quite capable of producing the enzymes needed to digest (break down into small pieces) the fiber found in plants. Ruminant herbivores, such as cows, sheep, deer, and goats, have this complex digestive system that is capable of efficiently digesting fibrous materials. They can take cellulose (one of the fibers found in hay, for example) and break it down into small molecules of simple sugar (known as glucose). In fact, if your goat gets hold of your cotton t-shirt, he can get glucose from it because cotton is the purest form of cellulose. Glucose is absorbed from the digestive system into the bloodstream, where it is transported to the animal’s cells to be metabolized for calories that keep the nervous system working, the heart beating, and the lungs breathing, as well as produce body heat and provide energy to do exercise.

I still haven’t told you about horses — that’s because horses are not like either one of these groups. They belong to a category known as “non-ruminant herbivores.” They are herbivores because they only eat plants. And they are non-ruminant because they do not have the four-chamber stomach that ruminants have. Instead, horses and all other equines, such as ponies, minis, donkeys, zebras, as well as the hippopotamus and the rhinoceros, have a digestive system that is a combination of ruminant and non-ruminant. They have a fermentation vat, called the cecum, that provides a home for fiber-digesting bacteria. But the cecum is toward the end of the digestive tract, and therefore not as efficient as the ruminant’s, whose fermentation vat (rumen) is toward the beginning. Therefore, horses need to consume much greater amounts of forages (hay and pasture) than cattle do to get the same number of calories.

Horses Need to Eat Hay and/or Pasture at All Times

The most basic approach toward keeping your horse healthy is realizing that horses are “trickle feeders.” This means that they require a continuous supply of small amounts of forage. Horses in their natural setting will graze virtually all day, while taking approximately 2 hours each day to rest (though not at all one time). This is a very important concept to understand because a horse’s digestive system needs to have food in it most of the time, in order to avoid digestive problems. Horses’ stomachs, unlike our own, produce acid continually and if a horse consistently goes for more than 3 hours without anything to graze on, the excess acid can produce ulcers, as well as diarrhea, behavioral problems (because the horse is in pain), and even colic. Chewing produces saliva, which acts as a natural antacid, so if a horse has no hay or pasture, he will chew on anything he can to create saliva; some horses will start to eat their own manure. Furthermore, not eating is very stressful for horses, which results in the secretion of stress-related hormones. These hormones promote fat storage. So, putting an overweight horse on a “diet” by reducing hay consumption actually works in reverse — it promotes more weight gain. In addition, the reduced forage availability will make his metabolic rate slow down, causing calories to be burned at a slower rate. This, too, results in weight gain.

Horses are capable of self-regulating their intake when given the chance. If they are only offered a set amount of hay at a time, they will likely eat it very quickly and will be anxious for more. But if given all they want, they will overeat at first (for a week or less) and then, once they see that they can walk away and relax and the hay will still be there when they return, they will calm down and eat only what they need to maintain a healthy weight. If your horse is stalled at night, the only way to know whether he has enough hay for this self-regulation to take place is for some hay to be left over in the morning.

Pasture and/or hay offered free choice will affect how your horse behaves. The more you treat your horse like a horse in the wild, the calmer and more cooperative he will be. He needs to graze continuously, and he also needs to be able to interact with other horses. Negative behaviors such as cribbing, pawing, and irritability are often alleviated by feeding more hay and providing turnout with his buddies.

Excerpt from Chapter 14 – Digestive Problems

Gastric Ulcers

An ulcer is an erosion of the tissue that lines the gastrointestinal tract. It can form anywhere along the digestive tract; however, ulcers are more commonly found in the stomach and therefore they’re called gastric ulcers. (Colonic ulcers are discussed in the next section.) Cells within the stomach lining produce a very strong acid known as hydrochloric acid (HCl). It is so strong that if you were to spill some on your hand, it would burn a hole in your skin. Fortunately, your horse’s stomach is protected by a thick mucous lining (or, rather, part of it is; we’ll look at the stomach in a minute).

Your horse produces HCl continuously, unlike our own stomachs where acid is only produced when we eat. He secretes acid all the time because he is designed to eat all the time. He is a “trickle feeder,” meaning he is supposed to eat small amounts, grazing virtually 24 hours a day, with intermittent stops to rest. Eating requires chewing and chewing produces saliva, a natural antacid that neutralizes acid so it doesn’t erode his stomach lining or have a chance to travel down the rest of his digestive tract, causing more trouble.

HCl sounds like a real nuisance, but it is actually quite necessary. Your horse uses it to start the process of protein digestion. Proteins are very long, tightly woven, complex molecules that need to be loosened and cut into more manageable pieces before they can be fully digested. HCl relaxes the protein structure, making the inner portion more accessible to digestive enzymes. And this same acid actually activates an enzyme in the stomach that starts to cleave off shorter strands of amino acids, a process that will be completed later, in the small intestine.

HCl has another important function — it protects your horse from infections. Horses eat off the ground, taking in mouthfuls of bacteria, viruses, and an assortment of organisms. Stomach acid is the first line of defense to kill those microbes. This is why I do not like long term usage of medications that neutralize acid. I’ll discuss those medications later.

So far, so good. So what causes an ulcer?

We do. Ulcers are caused by people. Horses rarely develop ulcers in natural settings. Basically there are four things we do to our horses that cause them to develop ulcers: We make them work, we cause them stress, we feed them lovingly but improperly, and we give them pain killers that wreak havoc with their digestive system. I’m here to help you find ways to reduce your horse’s risk of experiencing an ulcer, while still being able to work and perform.

Let’s start by examining each cause separately so you can take steps to prevent this painful condition. And later, I’ll tell how you can recognize, diagnose, and treat ulcers.

Reasons Ulcers Develop

Performance

When your horse moves, the acid in his stomach moves with him. To see how this affects his stomach, let’s take a closer look.

Your horse’s stomach is divided into two main regions: the lower, glandular portion, and the upper, squamous area. An ulcer in one of these locations is referred to as equine gastric ulcer syndrome (EGUS). The upper, squamous region does not have a protective mucous lining.

Looking at the picture above, it’s easy to can see how stomach acid can slosh around to the upper squamous portion when your horse is moving quickly. Events that require speed such as racing, barrels, cutting, or running in general, expose the squamous area to HCl’s caustic effect, creating a nasty sore. This is why most performance horses that run extensively will have an ulcer. In fact, 90% of all race horses have ulcers. Dressage, though a slower, more controlled discipline, involves repetitive movements and rigorous training that also leads to ulcers, but to a lesser extent, affecting approximately 40% of dressage horses.

The lower glandular region, unlike the squamous portion, is shielded from HCl by a thick mucous lining, but ulcers can still form in this area; not from running but from constant exposure to acid. That’s where stress comes into play.

Stress

Stress can take so many forms, I’ve devoted an entire chapter to it: Chapter 17 — Stress and Behavior. You know what stresses your horse. Things like an unfamiliar environment, a new barn, loss of a buddy, and introducing a new horse to the herd. But there are other stressors, some of which you may not have much control over, such as stalling, training, performance, and travel. Did you know that ulcers start to show up within three days of your horse’s first exposure to a continuing stressful situation? It may also surprise you to learn that a horse that is moved into a stall after being used to pasture turnout will develop an ulcer in less than a week.

Every horse is different; some become stressed over things that other horses barely notice. But one thing all horses share — they like routine. Any time you make a change, whether it is traveling to a strange location, starting a new training method, using an unfamiliar piece of equipment, or even changing his feed, your horse will respond by producing more stomach acid. If the stressor continues for any length of time, as your horse would experience by sudden stall confinement after living outdoors, your horse’s stomach, specifically the lower glandular region, will be bathed with a continuous supply of acid. This is why stress that lasts for hours or days leads to an ulcer so quickly. And as I’ve pointed out earlier, one of the most common and most preventable situations that predisposes your horse to an ulcer, anywhere along his digestive tract, is standing for hours without anything to eat. Speaking of which, let’s look at the next cause of ulcers.

Improper Feeding

The best way to avoid an ulcer is to allow your horse to be a horse. And the best way to do that is to give him pasture turnout — the more time, the better.

It not only gives him a steady supply of forage, but it lets him walk around, have a chance to run and buck, and visit with other horses. I realize that it is not always feasible to give your horse all the turnout he wants, but you’ll be happy to know that keeping hay in front of him at all times will go a long way toward protecting his digestive system.

Hay is wonderful. It absorbs stomach acid, requires more chewing which results in more saliva, and buffers stomach acid. In fact, ulcers may be completely avoided by giving your horse alfalfa hay; pellets do not offer as much buffering effect.

I know you understand my point, but you may be up against convincing your horse’s caregiver who may be stuck in old-school thinking. The best advice I can give you is to give this book to that person! I’m not trying to make anyone feel uncomfortable — well, maybe just a little: enough to sway you to change the way your horse is fed.

Do me a favor. You’ve heard me talk about this so much already, I’d like you to take the “Getty Challenge”: Offer your horse all the hay he wants for four weeks and let me know if he’s changed. No, I don’t mean if he’s gotten fatter — I mean his behavior. Is he happier and milder mannered? Does he respond to your commands better and give you his attention? Is he smoother under saddle? Oh, and the weight thing… don’t worry — he’ll eventually eat only what he needs to maintain a healthy weight.

Starch: You may not realize it but starchy feeds can lead to ulcers. Cereal grains stimulate the release of a hormone known as gastrin which tells the stomach cells to produce more acid; furthermore, they stay in the stomach for a relatively short period of time, leaving an empty stomach behind with all that acid. Hay and other fibrous feeds (such as beet pulp, hay cubes, and bran) take three times as long to leave the stomach.

Starchy feed has an additional impact on ulcer development. The stomach’s bacteria (Lactobacillus and Streptococcus) like to start fermenting starch, resulting in different acids — volatile fatty acids (VFAs). This further increases the acid content of your horse’s stomach.

So, in general, 2 lbs of starchy feed at a time is best, but never exceed 4 lbs (weigh your feed!) for an 1100 lb horse. And space your feedings approximately 6 hours apart to prevent accumulation of VFAs. In between those feedings, offer hay — lots of it. And remember the alfalfa; its buffering ability outshines any other hay source.

Pain Relievers

Enduring pain is stressful and can have the same effect as mental stressors on your horse’s health. But the risk is compounded by overusing nonsteroidal anti-inflammatory drugs (NSAIDs). These medications are often necessary, but they are not meant to be used for more than a few days.

NSAIDs such as phenylbutazone (bute) and flunixin meglumine (Banamine) can irritate the stomach lining enough to set up conditions for an ulcer. They inhibit cyclooxygenase (COX) enzymes. These enzymes stimulate prostaglandin production, which causes inflammation. But not all prostaglandins are harmful. Some are beneficial because they help produce mucus that protects the stomach. I offer a full description of how NSAIDs work along with safe dosing instruction in Chapter 11 — Laminitis.

Excerpt from Chapter 20 – Athletes

An athletic horse brings to mind one with speed, control, endurance, and the ability to focus, who is in top shape, muscular, and healthy, where every cell in his body works together to bring about the perfect form. His performance may be before the crowds or just between the two of you as you ride the trail, practice in the arena, or work on the farm. Whatever purpose you’ve given him, he relies on you to give him the best food, sufficient rest, and the care he needs to be your devoted partner.

Your athletic horse’s nutritional needs are enhanced, though they’re not especially different from other horses’. But the more work we ask of him, the more nutrients he needs to do the job and recover so he’s fit enough to do it again and again. This chapter examines how the diet should change when we ask him to work harder, to keep him sound and prevent injury.

The goal is to optimize his ability and performance so you — and he — can take pride in your shared accomplishments.

Nutrient Requirements

Variations Between Activity Levels

Before we discuss individual nutrients, I’d like you to see how your horse’s requirements change the more exercise he does. Using the nutrient requirements of an 1100 lb (500 kg) horse as an example, take a look at the trends rather than the exact amounts, since your horse’s weight may be considerably different.

Table 20-1 shows you the requirements for six key nutrients. Keep in mind that these are minimum requirements and your horse may be getting more than the table indicates. In most cases, that is perfectly fine; certainly it is for the nutrients shown in Table 20-1. However, some minerals, such as iron, zinc, and copper, need to be in proper proportion to one another to prevent competition for absorption sites within the digestive tract. And others, like selenium and iodine, are toxic in high doses. I’ll discuss these later in the chapter as I go through each nutrient classification.

For the most part, I’ll be speaking in generalities rather than giving you exact amounts to feed. There are as many combinations of ingredients as there are horses, so my goal is to arm you with information so you can create the best diet for your horse’s particular circumstance.

Digestible Energy

The term energy is synonymous with calories. It’s called digestible energy (DE) because it doesn’t account for fecal losses, but only for what actually gets absorbed into the blood stream. Your horse uses DE to do work, but it is also needed to sustain internal organs, secretions, digestion, and a multitude of bodily functions. Some of it is even given off as heat. But the bottom line is… the more your horse exercises the more DE he needs to maintain a normal body condition, inside and out.

If DE is insufficient, your horse will use his available stores for exercise, and actually mobilize (remove) nutrients from his own body tissues to meet the additional demands placed upon him. He’ll lose body fat and muscle mass, and his bones will thin. So it is critical for his health that his maintenance requirements be met first, followed up by additional calories for exercise.

For those of you who like to crunch numbers, the digestible energy calculations that follow3 can help you decide if your horse is getting enough calories to meet his work requirements. To use these formulas, you’ll have to convert your horse’s weight from pounds to kilograms; simply divide lbs by 2.2. For example, an 1100 lb horse weighs 500 kg (1000 divided by 2.2 = 500).

Protein

Protein has calories, but it should never be used to meet your horse’s DE requirement. Leave that to the carbohydrates and fat in his diet. Instead, protein should serve as a source of amino acids that your horse can use to build the proteins that his body needs. When we add protein to our horse’s diet, we generally think of building muscle mass, but that’s only one of hundreds of proteins in his body. Each tissue, whether it is muscle, bone, blood, liver, heart, arteries, skin, hair, hooves — the list goes on and on — has its own specific proteins which are made up of long, branched chains of amino acids. So the goal in feeding protein is to make sure that your horse has all the building blocks (amino acids) he requires to build and replace body tissues.

A protein source that has all the essential amino acids in proper proportion is considered complete and referred to as a high-quality protein. Chapter 4 — Fundamentals of Protein and Amino Acids discusses this in detail. But I’m not suggesting that you evaluate each feed for its amino acid content. Instead, you need to know just one simple rule: add a legume to cereal grains or grass to create a high-quality protein.

There are two commonly fed legumes — alfalfa and soybean meal. Soybean meal is actually much better because it comes very close to being a perfect protein source, with all the amino acids in their right proportion. Alfalfa is not as good, but still worthwhile, and boosts the overall protein quality of your horse’s forage intake.

If a legume is not added to your horse’s meal, the overall diet will likely be low in several amino acids. The one that tends to be the most limiting (low) is lysine. That’s why you’ll often see it added to horse feeds and supplements. But there are others that should be added and most commercial performance feeds will include methionine and tyrosine, as well as the branched-chain amino acids leucine, isoleucine, and valine. Your horse cannot produce these on his own; therefore they must be in his diet. If you mix your own ingredients, be sure to add a complete protein supplement to ensure that your horse is getting what he needs.

Take a look again at Table 20-1. Look at the crude protein and lysine requirements. As expected, they both rise as exercise gets more intense. But you need to be aware that crude protein is really just a measure of how many amino acids are in the feed; it tells you nothing about the specific ones or whether or not they’re in the right amounts.

Lysine requirements are shown to help you boost overall protein quality, but instead of adding a lysine supplement, add a legume to provide not only lysine but other essential amino acids. The overall protein intake should be 12-14% of the diet, and even more if your horse is still growing (see Chapter 19 — Growth and Growing Old).

Exercise Induced Pulmonary Hemorrhage (EIPH)

Any fast or intense exercise can cause the lungs to bleed. In mild cases you may not even notice it, and attribute your horse’s erratic behavior to nervousness.

In more extreme cases, however, there’s no missing the trail of blood coming from his nostrils. But no matter the severity, any blood in the lungs is a source of inflammation and potential infection. The more irritated and inflamed the horse’s lungs, the smaller the airways become, setting off a continuous cycle of bleeding with each subsequent performance.

There are many theories about the exact cause of EIPH, but there’s no doubt that poor nutrition can cause weakened capillaries. Add high blood pressure to the situation, which naturally occurs as heart rate increases, and it’s easy to see how these tiny blood vessels can rupture.

The way to prevent EIPH is to first take care of the lungs by providing clean air for your horse to breathe. Barns are notorious for fumes and dust. See Chapter 16 — Immunity Issues for ways to help your horse’s respiratory system stay healthy. Besides managing his physical surroundings, attention to his nutritional needs will make a difference. Ever know anyone who bruises easily — where just a slight bump causes a discoloration of the skin? That’s a sign of a vitamin C deficiency along with not enough protein. And it’s the same with your horses. Vitamin C produces the glue, collagen, that holds capillary cells together. If collagen production is diminished, capillaries rupture, plain and simple. Collagen is a protein; to make more your horse needs amino acids, building blocks of protein. If your horse’s diet contains low-quality protein, he will use what few amino acids he has to take care of more life threatening concerns — collagen production will be low on his list of priorities.

Please refer to Chapter 6 — Fundamentals of Vitamins for more information on vitamin C. Please pay attention to this vitamin. It is felt that supplementation is not necessary because horses produce their own vitamin C (whereas we cannot). And it’s true — they can produce vitamin C but their need may exceed their supply when stressed, both physically and mentally.