Horse Gastric Ulcer Syndrome: Prevention and Welfare

Equine gastric ulcer syndrome affects a high proportion of horses in work and causes significant pain, requiring both treatment and management changes for welfare improvement.

Key Facts

Equine gastric ulcer syndrome (EGUS) is estimated to affect 60-90% of racehorses and 37-50% of other horses
The equine stomach continuously produces acid unlike humans who produce acid primarily during meals
Forage intake buffers stomach acid - horses evolved to eat almost continuously
Periods without forage access exceeding 4-6 hours significantly increase ulcer risk
Omeprazole (GastroGard) is the gold standard licensed treatment for squamous ulcers
Glandular ulcers in the lower stomach are less responsive to omeprazole and harder to treat
Behavioural signs including reluctance to work, girthing sensitivity and poor appetite suggest ulcers
Endoscopy is required for definitive diagnosis - behavioural signs alone cannot confirm EGUS

Welfare Considerations

Gastric ulcers cause significant chronic pain in affected horses. The pain affects performance, behaviour and wellbeing throughout affected horses' daily lives. Girthing sensitivity, ridden resistance and reduced appetite are welfare-significant signs that are frequently managed with increased training pressure rather than recognised as pain signals. Prevention through management changes - ad libitum forage, reduced stress, smaller more frequent hard feed meals - is preferable to repeated treatment. Management-induced ulcers represent a welfare failure that can be largely prevented.

What You Can Do

Provide ad libitum hay or haylage access to minimise acid exposure to the stomach lining
Discuss diagnostic endoscopy with your vet if your horse shows girthing sensitivity or performance changes
Feed a small hay net before exercise to buffer stomach acid during work
Use alfalfa-based chaff as a pre-exercise buffer - it has demonstrated protective effects
Review stable management including forage access and social contact to reduce ulcer risk factors