According to Dr. Pamela Wilkins, an equine veterinarian at the University of Illinois, more than 90 percent of performance horses have ulcers. Stress is usually flagged as a factor - but how does stress cause ulcers in horses?

Interestingly, there's a specific physiological cause.

How does stress cause ulcers in horses?

Stress is much more than feeling a little upset. It causes the release of hormones in the body which cause all sorts of problems - in both horses and human.

The physiological cause and effect between stress and stomach ulcers is as follows:

Step One:

When horses are stressed they release a hormone called cortisol.

In an evolutionary sense it assists with the horse's 'flight or fight' response.

Step Two:

Cortisol lowers the production of prostaglandins in the stomach.

Prostaglandins help protect the stomach lining from stomach acid.

Step Three:

Prostaglandins have no impact on stomach pH, but they do PROTECT the stomach mucosa from the acid that is normally there.

The prostaglandin reduction leaves the stomach lining vulnerable to ulcers.

What causes a horse to stress?

Both physical and emotional/psychological stress can lead to ulcers.

A performance horse's lifestyle is vastly different from a horse in their natural state. Factors such as intensive exercise, travel and competition can all cause physical stress to a horse.

From an psychological perspective stabling, isolation and new environments can all cause a horse to stress.

What can be done to minimise stress?

Keeping a horse in as natural lifestyle as possible will help minimise stress. This means regular turnout, access to buddies and a diet with constant access to forage and minimal grains.

Obviously, for the performance horse there are triggers that cannot be avoided - like travel & competition. However, you can treat your horse with a preventative medication during periods of high stress.

Sucralfate is a product that forms a protective barrier over the horse's stomach lining. It's often used during travel, competition stressful situations to stop the formation of ulcers.

For more information: Sucralfate for horses: How it works and how to feed it.