Have you noticed changes in your horse such as weight loss, a dull coat, disinterest in feeding or crib chewing that have resulted in poor performance? Your horse might be experiencing stomach pain, most likely due to gastric ulcers.

Equine Gastric Ulcer Syndrome (EGUS) occurs when sores develop on the lining of the horse’s stomach. The physiochemical barrier that usually protects stomach tissue is worn down and digestive acids cause painful lesions in the stomach’s lining.

In addition to causing discomfort in your horse, gastric ulcers can present with hindgut ulcers which can impair nutrient absorption leading to a wide range of health and behavioural problems.

This condition is known to affect 60-90% of performance horses particularly when travel, high-intensity exercise and long periods without feeding occur. It also occurs at high rates in pleasure horses and young foals.

Research shows that any horse that undergoes stall confinement, has inconsistent access to feed, is fed grain or concentrates, or is trailered is at risk of developing ulcers.

This article will guide you through the different types of gastric ulcers, their causes, symptoms and how to treat and prevent ulcers in horses.

What are Gastric Ulcers?

Ulcers are painful sores that can occur along the entire digestive tract of horses but appear most commonly in the stomach and to a lesser extent in the hind gut. Equine Gastric Ulcer Syndrome (EGUS) is a scientific term that describes horses that have ulcers in their stomach.

The stomach has two main sections, the upper squamous region and the lower glandular region. The squamous region is particularly prone to ulcers developing.

Gastric Ulcers in Horses

The glandular region produces stomach acid, but also produces bicarbonate and mucous to protect the tissue in this area from the acid. These substances form a barrier that makes the lining of the glandular region less prone to ulcers.

The squamous region does not have these natural defenses against stomach acid and accounts for 80% of all gastric ulcers.

A horse’s stomach produces acid all throughout the day. This put them naturally at high risk for developing gastric ulcers, particularly during times when there is no food in the stomach to help buffer the acid.

In the wild, horses graze up to 16 hours a day. They are normally protected from ulcers due to the continuous presence of high-fibre food in their stomach.

However, horses kept in stall confinement with limited turnout during the day may go long stretches of time between eating. An empty stomach increases the risk of ulcers forming.

There are many other factors that contribute to the high rates of gastric ulceration in horses. These factors as well as strategies for mitigating ulcer risk like using Mad Barn’s Visceral+ ulcer support supplement will be covered in further detail below.


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Equine Ulcers Signs & Symptoms

How can you tell if your horse has ulcers? The only definitive way to diagnose EGUS in your horse is by having a veterinary checkup to perform a gastroscopy.

Your vet will look into your horse’s stomach and upper intestine with an endoscope to see whether there are ulcers present, how severe they are and their location.

But even without an exam by your vet, there are some common signs and symptoms to look out for as evidence that your horse may have ulcers. If you think your horse is affected, a visit from the vet to perform a scope is warranted.

Signs and symptoms of gastric ulcers in horses are generally non-specific and can vary greatly between horses. Many horse owners note that their horse is “just not looking right”.

Some common symptoms include: [1]

  • Poor appetite or “picky eating”
  • Poor body condition or weight loss
  • Chronic diarrhea
  • Poor coat condition or a rough coat
  • Bruxism or teeth grinding
  • A more aggressive or nervous disposition
  • Increased stereotypic behaviours such as cribbing
  • Acute or recurrent colic
  • Poor performance
  • Sensitivity in the girth area
  • Excessive recumbency
  • Stretching to urinate
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What Causes Equine Ulcers?

1. Diet and Feeding

Not only does feed composition affect ulcer risk but also the frequency and pattern of feeding. Horses have evolved to graze on pasture for the majority of their day, consuming roughage regularly.

Current equine management practices mean that many horses do not have regular access to pasture and can go long periods of time with no food in their stomach.

With intermittent feeding (i.e. having long intervals between meals), the horse’s stomach is empty, and the continuous production of acid irritates the lining of the stomach and can cause ulcers.

When a horse eats a meal, the food itself and bicarbonate from saliva neutralize the aci