Gastric ulcers in horses have an estimated prevalence 50-90% and most horses with ulcers have no overt signs of disease. Clinical signs of ulcers in horses are subtle and nonspecific and might be reflected in a slight attitude change, a decrease in performance, dullness, decreased or selective appetite, or a reluctance to train. Ulcers can affect any horse at any age and can lead to problems like colic, poor performance, weight loss, and bad behavior. To understand what causes gastric ulcers in horses it is important to understand the physiology and normal behavior of a horse.
The average equine stomach can hold 8-10L of contents, relatively small for an animal of substantial body mass, and is made up of glandular and non-glandular portions (unlike humans). The glandular portion, on the bottom, of the stomach is where acid is produced to help aid in digestion of foodstuffs. In a natural grazing situation, the horse requires a steady flow of acid for digestion, so a horse’s stomach produces acid 24 hours a day – up to 9 gallons of acidic fluid per day, even when not eating. In a natural, high-roughage diet, the acid is buffered by both feed and saliva. When the horse’s stomach is empty, acid produced by the lower stomach reaches an extremely low pH and can damage (ulcerate) the non-glandular portion of the stomach should it come into contact with it. Most ulcers in the equine stomach occur at the interface between the glandular and non-glandular portions of the stomach. Ulcers in the stomach can heal on their own, over time, but factors like stress and metabolic status can inhibit healing ability. This is why many people associate stress with gastric ulcers.
Unfortunately, signs of gastric ulcers can be very subtle so there is no way to know if your horse truly suffers from them by observing behavior. Signs of ulcers are also not proportional to the severity of disease. A horse with low-grade ulcers may exhibit more discomfort than a horse with more severe disease. The only way to truly diagnose ulcers is by direct visualization with a video camera (endoscope) in the horse’s stomach. To “scope” a horse for ulcers a video camera is inserted up the horse’s nose, swallowed, passed through the esophagus, and into the stomach, the exact same way a horse gets “tubed” for a colic episode. Horses are sedated heavily for this procedure to minimize discomfort and stress. The procedure is very safe, and a complete evaluation takes from 10 to 20 minutes. To allow for the best imaging of the stomach, horses must be fasted from food for 12 hours and fasted from water 2 hours prior to scoping. During the scoping procedure the veterinarian looks at all areas of the stomach and grades disease on a scale from 0 (healthy) to 4 (bleeding ulcers). Any evidence of disease warrants treatment, but a grading scale helps determine healing should a second scope be performed.
Treatment and cure for gastric ulcers has only been scientifically proven with a drug called omeprazole. Trade names for equine omeprazole are “gastrogard” and “ulcergard”. Gastrogard is the only proven, FDA-approved, treatment for equine stomach ulcers. Ulcergard is labeled for ulcer “prevention” instead of treatment, but they are the exact same drug owned by the same company. These medications work by directly inhibiting gastric acid production. The stomach is still able to produce enough acid for digestion, but eliminates the excess amount that causes ulcers. Other medications that are sometimes used in treatment of ulcers are Ranitidine and Sucralfate. These drugs, while shown to be effective in other species, have not been proven or disproven to be helpful in treatment of gastric ulcers in horses, but many swear by their efficacy.
The unfortunate reality of gastric ulcers is they are expensive to diagnose and expensive to treat. A horse newly diagnosed with ulcers will be treated with omeprazole once daily for a month and generally we recommend re-scoping horses at the end of their treatment protocol to ensure treatment was effective. The other reason we recommend re-scoping a horse is that the producers of equine omeprazole stand behind their product and will cover the costs of treatment should a horse fail to respond to the drug. Once ulcers have healed, it is then important to establish changes in management to decrease recurrence of disease. Generally we also recommend prophylactic omeprazole around times of stress (when your horse is sick, stall bound, trailering, horse
showing, etc.)
As you already know, gastric ulcers can affect any horse of any age, but there are some things you can do to help prevent this disease.
- 1. Feed small meals, high in fiber and low in sugar as often as possible.
This means allowing your horse constant access to forages like hay and grass. If you can not allow your horse free-choice forage, look into using a slow release hay net or grazing muzzle. A small quantity of good quality forage in your horse’s stomach throughout the day is the best way to prevent ulcers.
2. Consider adding a calcium-rich supplement to your horse’s diet.
Calcium has the ability to raise gastric pH (make it less acidic). Feeding alfalfa is an excellent way to achieve this. If you can’t get your hands on alfalfa hay, consider adding in soaked alfalfa cubes or pellets as part of your horse’s ration. Many ulcer supplements on the market are primarily calcium and work the same as feeding good quality alfalfa.
3. Reduce physical and environmental stress.
Increased levels of cortisol, the stress hormone, can decrease the body’s ability to heal itself.
4. Only use non-steroidal anti-inflammatory (NSAIDs), such as phenylbutazone (“bute”), flunixin meglumine (“banamine”), etc. when directed by a veterinarian.
While readily accessible to many and used commonly, these drugs can decrease the production of the stomach’s protective mucus layer, making it more susceptible to ulcers.
Concerned that your horse may be a victim of gastric ulcers?
This August 3H Equine Veterinary Services is holding a Gastric Ulcer Clinic at the hospital for a discounted rate to help promote awareness about equine gastric ulcers (and show off our shiny new scope!!). Anyone is eligible to participate in the clinic provided you can fast your horse overnight and get him/her to the clinic during one of the available morning time slots.
- Where? The clinic at 96 Poole Rd. East in New Hill, NC
- When?
Dr. Ashleigh Crowell: Wednesday August 13th
Dr. Candice Lorandeau: Thursday August 14th
Dr. Tracy Tinsley: Friday August 15th - How? Call our office for details at 919-363-1686
- Cost? $200 including scoping and sedation (normally $250 plus sedation)
- Criterion? Horse must be fasted overnight and appointment must be scheduled at the clinic during the given time period
