Equine Gastric Ulcer Syndrome: Welfare in Horses Under Stress

Equine gastric ulcer syndrome (EGUS) affects the majority of performance horses and is strongly linked to management practices, dietary patterns, and training stress, representing a major welfare challenge in horse keeping.

Key Facts

EGUS affects an estimated 60-90% of racehorses and 40-60% of pleasure horses in intensive management
Horses evolved to graze continuously; the stomach produces acid constantly, causing damage when it is empty for extended periods
Intermittent feeding, stabling without forage access, training stress, and NSAIDs are primary risk factors
Clinical signs include poor body condition, dull coat, reduced performance, changes in temperament, and colic episodes
Diagnosis requires gastroscopy (endoscopic examination of the stomach); presumptive treatment is often initiated based on history
Omeprazole (GastroGard) is the gold-standard treatment, typically given for 28 days; recurrence is common without management change
Hay or forage should be available ad libitum or at minimum 1.5-2% of body weight daily to buffer gastric acid
Management changes — continuous forage access, reduced stabling, and stress reduction — are as important as drug treatment

Welfare Considerations

Gastric ulcers cause significant chronic pain — horses with active ulceration may experience persistent discomfort that affects their behaviour, willingness to work, and social interactions. The high prevalence of EGUS across performance horse populations indicates that current standard management practices are systemically failing to meet horses' digestive needs. The conflict between performance management (restricted feeding, intensive training, frequent travel) and the biological requirements of a grazing species creates a welfare tension that cannot be resolved by medication alone without addressing underlying management causes. Horses that receive omeprazole treatment without management change typically re-ulcerate within weeks of treatment cessation. Long-term welfare improvement requires recognising continuous forage access as a basic welfare requirement, not an optional management choice.

What You Can Do

Ensure horses have access to hay or forage for the majority of the day, particularly before and after exercise
Seek gastroscopy evaluation for horses showing performance decline, temperament changes, or recurrent colic
Comply with the full course of prescribed omeprazole treatment and implement management changes simultaneously
Advocate for equestrian organisations to include EGUS prevention guidelines in their welfare codes of practice
Support research into stress-reduction management strategies for performance horses that reduce ulcer recurrence