What Causes Equine Gastric Ulcer Syndrome (EGUS)?
Gastric ulcers are sores from acid destroying your horse's stomach lining and esophagus. These sores, all referred to as lesions, erosions or ulcerations, may vary in size, number and severity. Horses of all ages suffer from gastric ulcerations, including foals.
Equine Gastric Ulcer Syndrome (EGUS) is used to express the complexity of the condition. EGUS is not a single, isolated condition but is a multifaceted disorder brought on by various factors such as feeding practices, stress, training and medications. To ensure the best prognosis, veterinarians and researchers must use a comprehensive approach to treat the ulcers and the underlying causes.
Equine Gastric Ulcers Causes
The primary cause of EGUS is an imbalance between the protective factors that shield the stomach lining from the damaging effects of acid and the aggressive factors that increase stomach acid production. Horses are natural grazers, and the reason why the equine digestive system works best from continuous forage consumption. The stomach becomes prone to developing ulcers when their natural feeding behavior is disrupted, and horses go long periods without access to forage or experience inconsistent feeding schedules.
Factors that Contribute to EGUS
Horses can develop ulcers at any age, but preventative action can minimize the risk. The main risk factors of EGUS are how and what horses eat and the stress levels they endure.
Below are common reasons that predispose horses to develop EGUS:
Feeding Practices
Insufficient access to forage and extended periods without food (fasting) can lead to increased acid production and ulcerations in the stomach lining. High-grain diets contribute to ulcer formation. Many horses fed concentrated feeds typically only receive a flake or two of hay twice daily and spend the rest of the day without access to forage. Feeding frequent small meals and providing free choice hay instead helps buffer the stomach acid and reduces the risk of ulcers.
Intensive Workouts
Performance horses in heavy training, such as racehorses, usually have food withheld before workouts. Horses that go extended periods without eating leave their stomach empty and susceptible to the damaging effects of the acid. When fasting is the norm, the result is erosion of the stomach lining and a horse with painful gastric ulcers. Studies show that exercise increases acid production and causes the stomach to empty faster. During training, gastric splashing occurs, exposing the entire stomach to acid and erosion.
Stress & Anxiety
Due to their sensitive nature, even the tiniest changes can create stress and anxiety in equines. Changes in routines, locations and diet can affect your horse negatively. Horses in rigorous training and competition may experience stress, which can elevate stomach acid levels, promoting ulcers. Transportation, stall confinement and herd dynamics are other stressors that impact acid production and the stomach lining.
Medication Use
Extended use of certain medications, especially non-steroidal anti-inflammatory drugs (NSAIDs), can compromise the protective barrier of the stomach, making horses more susceptible to ulcers. Consult your veterinarian for less invasive alternatives to managing your horse's pain and inflammation.
Treatment for Horses With EGUS
The most reliable way to confirm a diagnosis of gastric ulcers is an endoscopic examination. Some veterinarians diagnose EGUS based on typical clinical symptoms such as poor appetite, poor body condition, weight loss, dull coat, behavioral changes, colic-like symptoms and a decline in performance. Successful ulcer treatment is usually a combination of veterinarian intervention and management changes. The same approach is helpful in the treatment of ulcers as well as prevention:
- Oral medications (Omeprazole, Ranitidine and Sucralfate)
- Maintain feeding schedule
- Feed smaller meals frequently
- Increase turn-out time
- Mitigate stressful environments
- Limited use of NSAIDs
- Unlimited forage or grazing
- Less grain and concentrates
- Provide hay during hauling
- Feed small amounts of forage 1 to 2 hours before workouts
- Daily gastro supplements to support gut health
If your horse shows signs of gastrointestinal discomfort or you suspect the presence of ulcers, consult your veterinarian and equine nutritionist for a proper diagnosis, treatment protocol and a diet that provides energy for performance while reducing the risk of ulcers. Most causes of equine gastric ulcers are man-made, so reevaluating your horse’s nutrition, management and training regimen can significantly impact your horse’s gut health and overall well-being.