Is there a difference in the prevalence of gastric ulcers between stallions used for breeding and those not used for breeding?

Simple Summary Equine gastric ulcer syndrome is a common disease in horses worldwide, with different prevalences in various categories and breeds. It is divided into two different illnesses, based on the mucosa affected: Equine Squamous Gastric Disease, if it involves the squamous mucosa, and Equine Glandular Gastric Disease, if the lesions are located in the glandular portion of the stomach. The effect of sex on gastric ulcers, especially on the squamous mucosa, is not completely elucidated: some studies found a higher prevalence of lesions of the squamous mucosa in geldings and stallions, while others failed to identify a sex as a risk factor. The few studies on glandular lesions did not show any correlation between sex and ulcers. A paper investigating only Thoroughbred mares at pasture found that about 70% of them had gastric ulcers, especially on the squamous mucosa. The aim of this study was to determine the prevalence of the disease in a population of male horses, and determine if their breeding or sports career can influence the development of gastric lesions. Gastroscopies were performed in 101 males, after recording data about their breeding and exercise history, management, and presence of clinical signs. Breeding activity does not determine the presence or severity of gastric lesions in either mucosa, while exercise and a combination of both exercise and breeding is associated with ulcers in the glandular mucosa. Clinical signs are correlated only with the severity of lesions in the squamous one.Abstract Equine gastric ulcer syndrome (EGUS) is a worldwide disease, and includes two different syndromes, Equine Squamous Gastric Disease (ESGD), affecting the squamous mucosa, and Equine Glandular Gastric Disease (EGGD), affecting the glandular mucosa. These two diseases are present in different categories (different activities, ages, etc.) and breeds of horses. The effect of sex on gastric health is not clear: some studies found a higher prevalence of ESGD in geldings and stallions, while others found no influence of sex on the squamous mucosa. The few studies conducted on glandular diseases failed to identify sex as a risk factor. The only study on breeding horses, focused on Thoroughbred mares at pasture, found that 70% of them were affected by gastric ulcerations especially in the squamous mucosa. The aim of this study was to determine the prevalence of EGUS, ESGD, and EGGD in intact males while also investigating the potential influences of breeding and exercise activity on the occurrence and severity of the diseases. A total of 101 intact males were admitted for gastroscopic examination. Comprehensive data regarding their breeding and sports history, management, and presence of clinical signs were recorded. A statistical analysis was performed. Within this equine population, no discernible relationship was found between breeding activity and occurrence and severity of ESGD or EGGD. Exercise and a combination of exercise and breeding activities were found to be associated with the occurrence of EGGD. The presence of clinical signs was correlated only with the grade of ESGD in this cohort of horses.