Equine Gastric Ulcer Syndrome: Welfare, Diagnosis, and Treatment

Gastric ulcers are endemic in performance horses and cause chronic pain that significantly impacts welfare, requiring management change alongside medical treatment.

Key Facts

Equine gastric ulcer syndrome affects an estimated 60 to 90 percent of performance horses and 30 percent of leisure horses.
Two distinct regions are affected: squamous mucosa ulcers driven by dietary management and glandular ulcers with less clear aetiology.
Gastroscopy under sedation is the only definitive diagnostic method, as clinical signs are non-specific.
Omeprazole is the primary treatment for squamous ulcers; glandular ulcers are more resistant and require combined approaches.
High-starch concentrate feeds, limited forage access, and training stress are primary risk factors.
Post-treatment relapse is common without addressing underlying management risk factors.
Horses with ulcers show reduced performance, attitude changes, reluctance to work, and weight loss.

Welfare Considerations

Gastric ulcers represent a welfare crisis created by modern horse management that diverges fundamentally from the evolutionary design of the equine digestive system. Horses evolved to graze continuously, maintaining constant buffering of gastric acid by saliva and forage. Restricted forage, high concentrate meals, and training stress generate an acid environment that causes ulceration. The welfare impact is chronic pain affecting every aspect of horse life and work. Medical treatment without addressing management risk factors leads to rapid relapse. Welfare-protective management combines treatment with forage ad libitum provision, concentrate reduction, and stress minimisation through management and social environment improvement.

What You Can Do

Provide ad libitum forage access to prevent the gastric acidification that drives ulcer development.
Discuss gastroscopy with your vet for any horse showing performance decline or attitude change.
Complete full treatment courses with omeprazole and manage reintroduction of risk factors carefully.
Minimise training stress and ensure horses have social contact and turnout opportunities.
Monitor body condition and behaviour post-treatment to detect relapse before it becomes severe.