UNDERSTANDING THE TYPES, CAUSES, AND TREATMENTS OF EQUINE ULCERS

Amanda Picciotto Feitosa

August 22, 2022

Health

Equine ulcers have long been a common concern for horse owners.

Our understanding of ulcers has dramatically improved over time through medical advancement, and there is currently more nuance to the diagnostics, treatment, and management of horses suffering from these internal sores.

Gastroscopy and ultrasound have become more readily available, and their increased accessibility have allowed non-specialty practitioners more experience and a greater comfort level with these tools. These developments throughout the industry have led to more animals being correctly diagnosed and appropriately treated.

Jordan Lewis, DVM of Palm Beach Equine Clinic (PBEC) sees a variety of equine ulcer cases.

She breaks them down into three categories: gastric ulcer disease of the squamous mucosa, gastric ulceration of the glandular mucosa, and colon ulcers of the right dorsal colon.

Equine gastric ulcer disease of the squamous mucosa refers to the ulcers found on the stomach’s inner lining closer to the esophagus. They are primarily caused by exposure to stomach acid and vary in severity depending on the amount of time the stomach’s lining has been in contact with the stomach acid.

“We often see this increased stomach acid exposure with the squamous mucosa in performance horses due to the mechanical aspects of exercise and abdominal pressure,” said Dr. Lewis.

“The increase in acid production and contact time can also be seen in fasting animals and animals with delayed gastric emptying or slowed motility.”

Glandular mucosa describes the stomach lining around the pyloric region closer to the intestines. Ulcers found here are typically caused by a decrease in mucosal blood-flow as well as a decrease in mucus production, which normally serves as a protective barrier for the stomach lining. Stress and non-steroidal anti-inflammatory drugs(NSAIDS) such as phenylbutazone (“bute”) or flunixin meglumine (“Banamine®”) are the usual culprits in this case.

Similarly, ulcers found in the colon are also usually caused by stress and NSAID administration.

This leads to a decrease in the mucosal wall protection resulting in ulceration and inflammation.

“In some cases with colon ulcers of the right dorsal colon, we see minimal thickening noted on the right abdominal wall, but other times it can be more severe thickening with more ominous clinical signsof colic, fever, hypoalbuminemia (protein loss), ventral and limb edema, and diarrhea,” detailed Dr. Lewis

The tricky thing about ulcers is that they do not always present with the same symptoms in every horse. It can be difficult to know when it’s time to be a little more invasive in order to take a closer look at a horse’s digestive system. At a minimum, persistent symptoms warrant a veterinarian consultation.

“The range of symptoms can vary from mild to severe. The horse might be being a picky eater, or they might exhibit moderate to severe colic symptoms like signs of abdominal discomfort such as pawing or rolling,” said Dr.Lewis.

“Even still, some horses present with the only outward sign being poor performance.”

Dr. Lewis uses varying diagnostic tools for a complete understanding of the affliction. Sometimes she will perform the Succeed test, which is a fecal test that generally helps indicate the presence of ulcers. Another option is to perform a gastroscopy with a three-meter endoscope to see the stomach where both forms of gastric ulcers are found.

Ultrasound is the primary diagnostic tool to look for thickening of the right dorsal colon wall indicating ulceration in the colon. Basic bloodwork to determine total albumin, a protein made by the liver, also helps indicate more severe cases of colon ulcers.

Once a horse has been diagnosed with ulcers of any variety it’s important to begin treatment, especially since horses suffering from ulcers are predisposed to colic.

Because each type of ulcer disease has a different underlying cause, the treatment protocol and medications are also different.

Though omeprazole paste used to be thought of as the cure-all, today we know that it is only part of the puzzle. Dr. Lewis recommends an omeprazole paste for at least a four-week period and uses other medications in conjunction with this depending on what type of ulcer she is treating.

For horses that have ulcers of the squamous mucosa experiencing more severe, colic-like symptoms, Dr. Lewis adds a dose of sucralfate before meals to the protocol. If she finds ulcers in the glandular and pyloric region of the stomach, misoprostol and prostaglandin analog is used.

For ulcers of the right dorsal colon, sucralfate is used as a coating agent while misoprostol is used as a treatment. In addition to medication, some lifestyle adjustments can aid in maintaining an ulcer-free digestive tract.

“It’s helpful if we can provide a more natural, less stressful environment for these horses with continuous grazing on pasture or hay as well as more turnout,” said Dr. Lewis.

“Horses with gastric ulcers do well on adding alfalfa hay as a buffering agent before a grain meal, while horses with colon ulcers do well on a low-bulk diet, meaning less forage and a more complete feed-based pellet. Adding a psyllium-based supplement can be helpful for these horses too.”

Even with the best curative efforts, some horses can continue to suffer from ulcers, underscoring the importance of monitoring your horse for any changes even after treatment. Because sport horses have an increased likelihood of developing gastric ulcers due to exercise, their constant work also increases the odds of them have recurring ulcers. Personality and demeanor also play a part.

“Horses that have recurrent ulcer disease tend to be horses that internalize more and are stressed easily,” said Dr. Lewis.

She highlightedsome additional measures that can be taken to help continuously protect the stomach’s lining, noting the importance of a regulated diet and more opportunity to relax, as well as treatment with a prophylactic dose of omeprazole paste.

If you think your horse feels a little off from their normal behavior, it might be time to discuss different diagnostic options with your veterinarian. Trust your gut–it might just help your horse’s too.

Two horses grazing on green meadow

All photos courtesy of Amanda Picciotto Feitosa and Palm Beach Equine Clinic.

Palm Beach Equine Clinic is a leader in providing general care and preventative medicine to help keep your horse healthy and happy throughout their life. Having a veterinary partner you can rely on is essential for every horse owner, regardless of your horse’s lifestyle. Building along-term relationship with your vet allows them to better identify and treat each unique horse. To find out more, please visitwww.equineclinic.com.

Maria Sempe