Executive Summary

Ulcers in horses are among the most prevalent yet persistently underdiagnosed disorders affecting modern equine management. Across disciplines, horse ulcers, including equine gastric ulcers, hindgut ulcers in horses, and broader manifestations of equine ulcer syndrome (EGUS – equine gastric ulcer syndrome), represent a significant burden on welfare, performance consistency, and long-term soundness (Sykes et al., 2015; Andrews, 2007). These conditions are not limited to stomach ulcers in horses. Instead, research confirms a continuum of gastric ulcers in horses, horse digestive ulcers, and equine gut ulcers involving the stomach, cecum, and colon, driven by interacting physiological and management factors (Murray, 2013).

Introduction: When Small Changes Reveal Bigger Digestive Problems

In many professional barns, the earliest signs of ulcers in horses are not dramatic colic episodes but quiet behavioral shifts. A trainer may wonder, “Why is my horse girthy all of a sudden?” A farrier may notice increased resistance during routine handling. Owners frequently report that a horse is losing weight but eating, or that a horse has ulcers but no colic—classic scenarios reflecting subtle signs of gastric ulcers in horses (Sykes et al., 2015).

What Are Gastric and Hindgut Ulcers in Horses?

Ulcers are areas of mucosal erosion or gastric mucosal injury that develop when protective mechanisms fail to counter acid exposure, fermentation byproducts, or inflammatory stress. In horses, gastrointestinal ulcers must be classified by location to be managed effectively.

Equine Squamous Gastric Disease (ESGD)

Equine squamous gastric disease (ESGD) affects the upper, non-glandular stomach. This region lacks mucus and bicarbonate protection, making it vulnerable to acid splash ulcers in horses, particularly during exercise. Squamous ulcers in horses are closely linked to fasting, high-intensity work, and disrupted feeding schedules (Luthersson et al., 2009).

Equine Glandular Gastric Disease (EGGD)

Equine glandular gastric disease (EGGD) involves the lower, glandular stomach. Unlike ESGD, glandular ulcers in horses are driven by impaired mucosal defense, inflammation, reduced blood flow, stress physiology, and NSAIDs and horse ulcers, including phenylbutazone ulcers in horses (Sykes et al., 2015; Andrews, 2007).

Hindgut Ulceration and Colonic Injury

Hindgut ulceration in horses, including patterns consistent with right dorsal colitis horses, occurs in the cecum and colon. These lesions are strongly associated with high starch diet horses ulcers, starch overflow hindgut horses, microbial imbalance, and intestinal barrier dysfunction in horses. Because direct visualization is limited, hindgut health in horses is often underestimated in routine practice (Murray, 2013).

Subtle Signs, Behavioral Changes, and Performance Decline

Professionals often encounter behavioral signs of ulcers in horses long before obvious digestive disease. These include girth sensitivity (girthy horse ulcers), resistance under saddle, anxiety, and reduced willingness to work—scenarios frequently described as horse refusing saddle ulcers or horse acting aggressive ulcers.

Management and Prevention: Whole-Gut Governance

Effective prevention of equine gut ulcers requires governance rather than isolated intervention. Continuous forage access, starch control, stress reduction, and cautious medication use support equine stomach health and hindgut stability simultaneously. These strategies align with professional observations that durable improvement follows system correction, not repeated short-term treatment (Sykes et al., 2015).

The Gut–Immune–Performance Axis

The gut is central to immune regulation. Barrier compromise allows inflammatory mediators to influence musculoskeletal recovery, ehavior, and metabolic efficiency. This connection explains why managing digestive issues in horses often improves performance and temperament beyond gastrointestinal comfort alone (Whitfield-Cargile et al., 2022).

Conclusion

Ulcers in horses, whether expressed as equine gastric ulcers, hindgut ulceration, or broader equine ulcer syndrome, reflect predictable interactions between diet, stress, microbial balance, and physiology. For professionals, the priority is not simply treating lesions but managing systems to prevent recurrence. Recognizing ulcer signs in horses, applying appropriate diagnostic tools, and addressing root causes remain the most effective strategies for long-term equine digestive health

Frequently Asked Questions

Q1: How to tell if a horse has ulcers without obvious colic?

A: Many horses with ulcers show behavioral and performance changes rather than acute pain, including girthiness, resistance, appetite fluctuation, or free fecal water.

Q2: Can horses have ulcers without colic?

A: Yes. Both gastric and hindgut ulcers may present without classic colic signs, particularly in chronic or low-grade cases (Murray, 2013).

Q3: Are blood tests accurate for horse ulcers?

A: Current evidence suggests blood-based tests and permeability assays should be used as supportive tools rather than definitive diagnostics, especially for hindgut disease (Ludwig et al., 2023).

 Call to Action

If a horse demonstrates persistent behavioral change, performance decline, or unexplained digestive instability, early evaluation using a whole-gut framework is recommended. Collaboration with veterinary professionals to localize disease and adjust management drivers is the most reliable path to sustainable outcomes.

References

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