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Why Is My Horse Not Eating Grain, But Eating Hay?

Why Is My Horse Not Eating Grain, But Eating Hay?

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The purpose of this blog is to share general information and is written to the author's best knowledge. It is not intended to be used in place of veterinary advice. For health concerns, please seek proper veterinary care. In addition, as an Amazon Associate I earn from qualifying purchases.

Horses are amazing creatures who add incredible richness and purpose to their owners’ lives. Caring for horses is a labor of love as they do not make the job easy; in fact, most horses seem to spend a large amount of their time contemplating how to die or injure themselves.

A horse who stops eating its grain is guaranteed to drive their owner around the bend with worry!

Horses will often continue to eat their hay but refuse to eat their grain if:

  1. It’s a new feed, e.g., a low-sugar, high-fiber feed
  2. The grain is compromised, e.g., moldy
  3. There is medicine or too many supplements in it
  4. They’re stressed at mealtime
  5. They’re in pain, e.g., equine gastric ulcers

While most pasture-based leisure horses can maintain their weight on the grass, hay, and teff consumed, concentrated grain feeds are essential sources of nutrients and vitamins.

Horses who go off their hard feed won’t receive the energy and nutrient benefits of hard feed and may be suffering from an underlying medical condition.

Why Do We Add Grain to a Horse’s Diet?

Not all horses need concentrated grain foods added to their diet. Many horses who do not have elevated energy requirements and graze on good quality grass will not benefit from additional supplementation.

However, horses with increased energy demands like breeding stallions, broodmares, and competitive horses need the additional energy supplied by grain feeds.

Grains are packed with nutrients and minerals not commonly found in many pastures and thus ensure that your horse has a well-balanced diet. Horses in poor health, recovering from an illness, or grazing on nutrient-deficient pastures will benefit from a grain supplement.

Feeding grain allows owners to monitor their horses’ appetites. It can be challenging to detect minor changes in appetite unless the horse is stabled and fed a measured amount of grain and teff.

Feeding a small grain meal once or twice a day to paddocked horses allows owners to monitor their horses’ appetites confidently, even if the grain amount is too small to noticeably impact your horses’ condition.

Identifying the Underlying Reasons for Poor Appetite

Horses Eating

Horses that refuse to eat grain or go off their regular grain feed are a source of great concern to their owners. Horses who go more than four hours without eating are at risk of developing gastric ulcers, a chronic condition with potentially serious long-term consequences.

The key to successfully treating abnormalities in your horse’s appetite preferences is finding out why your horse is happily eating their hay but refusing their grain.

The causes behind selective eating and refusal of grains may be benign and easily fixed or due to more concerning chronic medical conditions.

Is Your Horse a Fussy Eater?

Horses like humans have individual taste preferences. A grain type that one horse adores and jealously guards is the exact grain that another horse will take one disdainful sniff of and walk away.

Horses are naturally cautious eaters and avoid novel foods, i.e., grains they have never encountered before. This naturally fussy behavior is a crucial survival skill as it ensures that horses avoid eating unknown and potentially harmful feeds.

Horses with laminitis, Cushing’s disease, insulin resistance, and other metabolic conditions are often put onto high-fiber, low-sugar diets. These feeds are essential for delivering the needed nutrients but are not the most palatable feeds. Some recalcitrant horses prefer to go on a hunger strike (or at least not eat their grain) to protest the forced sugar-free diets.

How to Make Your Horse’s Food More Palatable?

Feeding a Horse By Hand

It is crucial to always introduce new feeds to your horse slowly over ten to fourteen days. The gradual introduction is essential as it allows your horse’s gastrointestinal tract bacteria to adapt to the news feeds and prevents gas colic. Gas colics are a common sequela of rapid food changes and bacterial death in the gastrointestinal tract.

In addition to avoiding colics, slowly introducing your horse’s palate to a new food type allows them to become accustomed to it. Mixing your original food with the new food during the transition period allows your horse to feel comfortable eating a “known” food while acclimatizing to a different taste.

Horses who need to go onto low-sugar, high-fiber diets for medical reasons will often accept their fate more graciously if the transition from tasty but unhealthy food to bland but healthy food is done slowly.

Horses are notorious sweet addicts and will perform all manner of tricks to get a lick of high-sugar feeds. Sweeteners may be added to the grain meal to improve the taste. Both molasses and honey are common ingredients added to the grain to entice picky eaters.

Is Your Horse Refusing to Eat Comprised Feeds?

If your horse appears to be healthy but refuses to eat his grain while still eating his hay, it may be that your grain has been compromised. A horse’s sense of smell and taste is much more acute than a human’s. Thus, horses are easily able to detect changes in food that may be unnoticeable to their owners.

Before labeling your horse a fussy eater, it is essential to check if the issue is the horse or the food. Grains and supplements may become moldy, infested with rodent droppings, grow fungi, or become rancid if stored incorrectly. Forcing your horse to eat these foods will be detrimental to your horse’s health.

If your horse refuses to eat their grain, try opening a new bag and feeding them some food from that bag. If your horse eats the “new” grain, the issue is the food, not your horse.

It is essential to keep in mind that occasionally food is compromised at the manufacturer or retailer. Thus a horse’s refusal to eat fresh grain should not be dismissed as it may still indicate a food quality issue.

Unintentional Mycotoxin Poisoning in Horses

Various Grains for Horses

Mould or fungi in grains occasionally produces a secondary toxic compound, known as mycotoxins. There are a variety of mycotoxins that can remain undetected in a horse’s grain as they are odorless, colorless, and tasteless compounds.

Signs, Symptoms and Treatment of Equine Mycotoxin Poisoning

The horse’s stomach is not equipped to deal with mycotoxins, and the active mycotoxin passes through the acidic stomach without damage. The mycotoxin is then passed into the small intestines, affecting the intestinal walls and being absorbed into the horse’s bloodstream.

There are more than 300 mycotoxins, but the most toxic to horses is mycotoxin fumonisin. Mycotoxin fumonisin poisoning causes a fatal neurological condition in horses called equine leukoencephalomalacia. Initially, the horse presents with a loss of balance, lack of coordination, and blindness followed by death.

Binding agents like activated charcoal and yeast cellulose are used to bind and deactivate the mycotoxin until safely eliminated. Binding agents are not effective in cases where the mycotoxin has already been absorbed into the horse’s bloodstream.

Ensuring Your Horse Food Is Stored Correctly

A few fundamental principles must be adhered to to keep your horse’s hard feed fresh and mold-free.

Most grains remain fresh and safe to feed for up to three to four weeks after opening the bag. However, a few supplements have a shorter shelf-life and need to be fed more quickly.

Many horse owners add oil, i.e., coconut oil, sunflower oil, and vegetable oil, to their horse’s feed to improve the horse’s coat quality and increase weight gain. Most oils are notoriously unstable and quickly become rancid at high temperatures (40° Fahrenheit) when exposed to air.

If you add oils to your horse’s diet, it is best to store the oil in a cool room or even a fridge.

Grains and supplements should be stored in a cool, dark room in sealed containers. Mold and fungus love to grow in warm, humid environments. It is virtually impossible to eradicate mold spores from the air, and thus it is more effective to ensure you don’t provide the perfect mold-growing conditions.

Storing your horse’s hard feeds in airtight sealed containers will prevent rats and mice from getting into the feed and tainting the food with their feces.

Always buy your horse feed from reputable sources to prevent contamination of feed during the manufacturing and pre-sale storage processes.

Are Supplements Turning Your Horse Off Their Feed?

Person Feeding Horse By Hand

Many owners feel that you need to add supplements to our horses’ diet to ensure they remain happy, healthy, and in peak condition.

It is easy to overdo the supplements. I mean, which horse doesn’t need an immune booster, shiny coat oil, calming supplement, and supplements for their bones and joints along with their scientifically balanced grain meal? While owners may feel better because they can give their horse every conceivable supplement on the market, this practice is rarely beneficial for the horse.

Most supplements are formulated to address a specific deficiency or health condition and are not designed to be highly palatable, which is why they are fed with the horse’s grain meal.

Too many supplements may put your horse off their food. After all, it’s the equivalent of adding every spice you have into a single meal. The individual spices are fine, maybe even tasty, but adding twenty spices to one dish will have disastrous results!

Horses requiring oral medicines may avoid eating grain containing these medications, much to their owner’s frustration.

Addressing Over Supplementation in Your Horse’s Diet

It can be challenging deciding which supplements are necessary to your horse’s continued well-being and which are unnecessary additives that turn your horse off its feed.

When deciding which supplements to discard and which to keep, the first step is to speak to your vet and an equine nutritionist. Working together, your vet and nutritionist will formulate a palatable, well-balanced diet that meets all of your horse’s needs.

Based on your horse’s medical state, metabolic demands, and the cost of feed, they may recommend ONE or TWO supplements – not five or more! Both your horse and your wallet will be grateful for keeping your horse’s diet simple.

The next step to justifying the use of supplements is to find out whether science validates the manufacturer’s health claims. Many supplements claim to have excellent results and yet cannot provide scientific evidence to support those claims; these supplements are most likely a waste of money!

The third point to consider regarding supplements that have made the “keep” list is whether there are more palatable options that provide equivalent results.

How Does Stress Affect Your Horse’s Appetite?

Horses who are stressed may become distracted and unable to focus on finishing their meal. These horses will often restlessly pace, whinny, paw, and show other signs of distress. The most common cause of stress-related failure to eat is when horses are separated from their paddock mates.

Horses need other horses to feel safe and confident. Anxious horses will often present as herd-bound and become overly anxious when taken away from their friends. The best way to lower your horse’s stress is by helping your horse develop confidence and trust in its handler.

The Link Between Equine Gastric Ulcers and Appetite

Close Up of Horse Eating

Gastric ulcers occur when the lining of a horse’s stomach is “eaten away” or compromised by the stomach’s acidic secretions. Gastric ulcers are most common in fit athletic horses, horses who have been starved for more than four hours, stressed horses, and horses with a pH imbalance.

Horses who fail to thrive, show behavioral changes, and refuse to eat their grain while continuing to eat their hay should be assessed for gastric ulcers.

Symptoms of Equine Gastric Ulcers

  1. Poor appetite, especially in horses refusing to eat rich foods like grain
  2. General apathy and lack of interest in their surroundings
  3. Increased aggression and irritability
  4. Aversion to having the girth done up or the rider using leg aids
  5. Low-grade colic and weight loss
  6. Loss of general body condition, e.g., a dull, coarse coat
  7. Reluctance to canter, jump or do other fast work

How Are Equine Gastric Ulcers Diagnosed?

Gastric ulcers are definitively diagnosed with a procedure called an endoscope. During an endoscope, a small camera is passed into the stomach, and the stomach lining is examined for any damage or abnormalities.

Vets who do not have access to the necessary facilities and tools needed to perform an endoscope may choose to treat a horse for gastric ulcers based on clinical suspicion.

How Are Equine Gastric Ulcers Treated?

Equine gastric ulcers are treated with the USA-legal Omeprazole and Sucralfate. Omeprazole reduces the acidity of gastric acid while sucralfate coats the ulcer providing symptomatic pain relief.

Horses with gastric ulcers are often put onto an ulcer diet:

  1. The horses are given free access to good quality hay, teff, and grazing
  2. Horses are fed small meals throughout the day
  3. Increase Alfalfa (lucerne) intake, although it should be less than 50% of the total roughage fed; lucerne lowers the gastrointestinal pH.
  4. Grain quantities are reduced as much as possible, and the nutrient requirements are made up of high-quality roughage.
  5. Decrease the use of anti-inflammatory drugs and lower the horse’s stress levels
  6. Reduce the intensity of the horse’s training program until the ulcer is fully healed

Final Thoughts

In the wild, horses do not eat grain; instead, they live off grass, leaves, and other plant material they forage. However, grains are an essential component of the modern horse diet, as these horses have:

  1. Increased metabolic demands due to their life as a ridden horse
  2. May have chronic conditions which would kill a wild horse
  3. Rarely have access to multiple grass types available for self-selected grazing

A horse may choose not to eat their grains due to compromised feed that is moldy or rancid, over-supplementation, the inclusion of oral medication, stress, and equine gastric ulcers.

Horses are naturally fussy eaters who prefer sweet feeds. New grains and low-sugar concentrates will be regarded with suspicion and should slowly be introduced to the horse’s diet during an acclimation period.

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