EQUINE Gastric Ulcer Syndrome (EGUS) is often framed as a ‘thoroughbred problem’, but reality tells a very different story.

Studies suggest EGUS affects up to 90% of performance horses and a significant proportion of leisure horses. While racehorses may approach a near 99% prevalence, ulcers are also widespread in show horses, jumpers, endurance athletes, ponies and even feral horse populations. This clarifies that EGUS is not a breed-specific issue, but a management one. The common denominator is not the thoroughbred; it is the way we care for horses in modern management systems that often conflict with their natural biology.

Constant intake

Horses are designed to be continuous foragers. If allowed, they spend up to 18 hours a day roaming, browsing and chewing fibre-rich plants. This constant intake stimulates chewing, saliva production and buffering stomach acid, while the act of foraging stimulates vagal tone, reducing stress. When we interrupt this natural pattern with restricted forage and intermittent feeding, we remove key protective mechanisms and increase the risk of gastric ulceration. Despite best intentions, human convenience often dictates equine management.

Anthropomorphism plays a role; owners may feel they are providing comfort with a tidy haynet and a ‘cosy’ stable. But from the horse’s perspective, welfare is better defined by the ‘three Fs’: forage, friends and freedom to move. Stall confinement, limited turnout and meal feeding directly oppose these needs, creating conditions where issues like EGUS can run rampant.

Thoroughbreds in training frequently experience these constraints most acutely, with high-starch diets, restricted forage and exercise on relatively empty stomachs. However, this does not make the breed inherently fragile; it reflects the intensity of their management.

Natural behaviour

Encouraging natural foraging behaviour is key. Offering multiple fibre sources, such as hay, haylage, alfalfa and beet pulp, can improve intake, particularly in horses transitioning out of racing. Offering forage in social, outdoor settings can further promote natural behaviour.

Simple nutritional strategies can also help. Providing forage before exercise creates a fibrous mat in the stomach, reducing acid splash. Likewise, choosing low-starch, high-fibre feeds, such as Red Mills Care Range products can support digestive health. Ultimately, EGUS is not about breed; it is about how closely we align management with the horse’s natural way of living.