Equine gastric ulcer syndrome

Equine Gastric Ulcer Syndrome (EGUS) is a complex condition affecting horses, characterized by the development of ulcers in the stomach and, occasionally, the upper part of the small intestine. This condition is of significant concern within the equine industry due to its prevalence and impact on the health and performance of affected horses. EGUS is divided into two main categories based on the location of the ulcers: squamous and glandular gastric ulceration.

Etiology

The development of EGUS is multifactorial, with several risk factors contributing to its onset. These include stress (e.g., from training, transportation, or confinement), dietary management (such as infrequent feeding or high-grain diets low in forage), and the use of non-steroidal anti-inflammatory drugs (NSAIDs). The condition is prevalent in horses of all ages and backgrounds, from elite performance horses to leisure horses.

Pathophysiology

The horse's stomach is divided into two distinct areas: the squamous and the glandular regions. The squamous region is more prone to ulceration due to a lack of protective mechanisms against the acidic gastric environment. In contrast, the glandular region has a mucus-bicarbonate barrier and other protective factors. Ulcers form when there is an imbalance between aggressive factors, like stomach acid and pepsin, and protective mechanisms.

Clinical Signs

Clinical signs of EGUS can vary widely and may include poor performance, weight loss, poor condition, changes in eating behavior (such as decreased appetite or reluctance to eat), colic symptoms, and in severe cases, bleeding ulcers can lead to anemia. However, some horses may show no outward signs despite having significant ulceration.

Diagnosis

Diagnosis of EGUS is primarily achieved through gastroscopy, which involves passing a flexible endoscope into the stomach to directly visualize the ulcers. This procedure requires the horse to fast and is performed under sedation. Other diagnostic methods, such as blood tests and fecal occult blood tests, can suggest the presence of ulcers but are not definitive.

Treatment

The mainstay of treatment for EGUS involves reducing gastric acidity and enhancing mucosal defense mechanisms. Proton pump inhibitors (PPIs), such as omeprazole, are the gold standard for treating EGUS, effectively healing ulcers by inhibiting gastric acid secretion. H2 receptor antagonists and antacids may also be used, though they are generally considered less effective than PPIs. Alongside pharmacological treatment, management changes, including increased forage intake, frequent small meals, and reducing stress, are crucial for prevention and management of EGUS.

Prevention

Preventative strategies for EGUS focus on minimizing risk factors. These include providing a high-forage diet, ensuring frequent, small meals to reduce the time the stomach is empty, minimizing stress through environmental and management changes, and cautious use of NSAIDs.

Conclusion

Equine Gastric Ulcer Syndrome is a significant health issue in horses, affecting their welfare, performance, and quality of life. Understanding the risk factors, recognizing the clinical signs, and implementing effective treatment and management strategies are essential for preventing and managing this condition.