Managing Gastric Ulcer-Sensitive Horses

It can be challenging to manage a horse that tends to act ulcery  for days, weeks or months after gastric ulcer treatment.  The horse goes back onto ulcer medications, gets better, is taken off the meds, and then starts acting ulcery again. What we have learned is that some of these horses don’t actually have full-blown ulcers, but they do have an ulcer sensitivity, meaning a gastric acid irritation of the mucosa lining the stomach.

Horses are biologically designed to live in groups, wander and eat forage 20 hours a day, and be strong and agile to run from predators.  Horses produce more than 10 gallons of saliva per day when they are constantly eating. The brilliance of the biological design of the horse is that the horses’ salivary glands produce bicarbonate, which buffers and protects the lining of the stomach, and raises the pH.  Included with the bicarbonate is the enzyme amylase, which breaks down carbohydrates.

The equine stomach
A horse’s stomach is divided into two parts: the non-glandular portion and the glandular portion.  The non-glandular portion lacks a significant mucosal layer, making horses predisposed to squamous gastric ulcers.  Research has indicated that lower stomach pH can be affected by dietary components; high-starch foods can lower the pH, while alfalfa for instance raises the pH, thus buffering the gastric acid in the stomach and having a protective effect on the squamous mucosa.

One study showed that a diet high in NSCs (non-structural carbohydrates, as found in oats and barley) caused less saliva production and a more rapid fermentation, resulting in the production of volatile fatty acids (VFAs).  In the presence of low stomach pH, VFAs are absorbed into the squamous cells, which inhibits cellular sodium transport and can predispose horses to squamous ulceration.

Ulcers that form in the glandular portion of the stomach are generally caused by a breakdown in mucosal defense mechanisms, rather than excessive exposure to gastric acid.  NSAIDS can contribute to formations of ulcers in the glandular portion.

The horse under saddle
When horses are working, the natural bicarbonate protection of saliva is halted.  When the non-glandular portion is left unprotected, gastric acid can splash and irritate the mucosa, even causing an acid burn.

Remember: the gastric acid in the stomach is being produced all the time, not just when the horse is eating.

In fact, exercise increases gastric acid production, expanding the opportunity for mucosa irritation and burn.  A horse’s biology is designed for quick periods of running away from danger.  Wild horses may run a few hundred yards or even half a mile to get away from predators.  Then they go back to eating.  But when we train horses, we are working them an hour or more each day — a much longer time spent without the benefit of the food/saliva buffering mechanism.

Management of the ulcer-sensitive horse

Some tips and points to consider:

• Studies have shown that foods high in NSCs result in higher VFA production and therefore greater potential for squamous mucosal injury. Even feeds labeled as “low starch” may have a combined sugar and starch content of over 20%.  Truly low NSC means 12% or less, and for metabolic horses it is 10% or less.
• Horses need to eat 20 hours per day. It is extremely important to make sure the horse has hay or forage and doesn’t go longer than four hours in a 24-hour period without eating.
• Stress is a huge component in the formation of ulcers. Trailering, showing, training, changes in personnel at the barn, human stress in the environment, isolation, loss of an equine buddy, change of barns, injury — all of these things can contribute to increased ulcer formation. Reducing the cortisol produced by acute stress or chronic stress is important: herbs such as ashwaganda, holy basil, ginseng and Rhodiola rosea provide cortisol-lowering actions.
• Adding aloe to the feed (¼ to ½ cup per feeding) can help coat the GI tract and protect the mucosa. High-quality distilled aloe is more expensive in the short term, but you use less of it per feeding.  I recommend George’s Distilled Aloe.

Management of the ulcer-sensitive horse under saddle

• Because alfalfa raises the pH in the stomach and provides calcium to help buffer acid, feeding alfalfa before exercise can be helpful to the ulcer-sensitive horse.  Alfalfa hay is also very high in protein; if needed, a good alternative source is alfalfa pellets or cubes, which have a lower protein content.
• Walk breaks during a training session are not only important for muscle recovery, but help reduce the amount of gastric acid being pumped.  Remember: the biology of the horse is structured around eating, quickly running away from the predator, then relaxing and eating again.
• Sugar cubes are common treats for performance horses, but sugar is one of the components that elevate the volatile fatty acids in the stomach, resulting in the inhibition of sodium transport and an increase in squamous ulceration.  Riders and trainers may like to see the “white lipstick” of foam around a horse’s mouth that sugar helps produce, but it’s far better for the ulcer-sensitive horse to get a small handful of alfalfa pellets instead.  We need to adjust our perception of white lips versus green lips.

BioStar’s Tum-Ease EQ
This unique formula was created for my own ulcer-sensitive horse, Lionheart.  It is designed in a cookie form to be given as you are tacking up.   What makes Tum-Ease special is the micro-crystalized aloe vera; it works like the drug sucralfate,  which acts as a local mucosal adherent.  Sucralfate is a sort of   band-aid for gastric lesions and irritated mucosa.  Micro-crystalized aloe is a therapeutic/pharmaceutical grade of aloe vera not available in stores, but often used in hospital burn units.  It is an incredibly expensive aloe at $250 a pound.

The micro-crystalized aloe in Tum-Ease goes to work protecting the mucosa from the gastric acid splash, and helping soothe any mucosa that is already irritated.

Tum-Ease also provides cabbage for its high content of the amino acid glutamine.  This amino acid provides nitrogen to the immune cells of the intestinal mucosa and helps stimulate the synthesis of mucoproteins that increase mucin.  A key characteristic of mucin is the ability to form gels, serving various functions such as lubrication, cell signaling, and creating protective barriers.

Another important ingredient in Tum-Ease is non-GMO papaya.   This tropical fruit increases mucus production in the stomach, esophagus, and mouth.  Papaya can aid in thickening the mucous lining in the stomach that serves to protect against increased gastric acid production.

You can carry Tum-Ease bars in your pocket, as a training reward for your horse during a ride. Because they are dehydrated, they won’t fall apart like sugar cubes if your pockets get wet, and they won’t create a sticky mess.

Keeping in mind the essential biology of the horse is important in the management of horses sensitive to gastric ulcers.  The good news is, these horses can be managed relatively easily by focusing on diet, lifestyle, pre-exercise food, and plenty of walk breaks during the training session.