Equine gastric ulcer syndrome (EGUS) is extremely common in performance horses and is directly linked to management practices that conflict with horses' natural physiology.
Gastric ulcers cause chronic pain that affects performance horses' daily welfare and behavioral responses. The pain is often most acute during feeding or immediately after exercise, which may explain resistance and behavioral changes that owners and trainers may misinterpret as training problems. The irony is that the very management practices that maximize performance — stabling, restricted forage to prevent weight gain, concentrated feeding, intensive training — are the same practices that cause ulcers. Management changes to prevent ulcers often require accepting horses at slightly higher body weight or reduced intensity, which requires cultural change in performance horse circles.