In recent years, gastric ulceration has been recognised as a common, possibly performance-limiting disease of adult horses. Here, we aim to provide the reader with a useful review of recent literature covering all aspects of equine gastric ulcer syndrome (EGUS) in adult horses. The anatomy and physiology of the stomach, with particular reference to secretion of acid and mucosal protective mechanisms, are reviewed, as are the differing theories relating to the aetiopathogenesis of gastric ulceration. We also explore the possible influence of various management factors on development of the disease. The prevalence of the disease in racehorses has been reported to be as high as 100%. In general, horses that are in active training for racing tend to have a prevalence of around 90%, whereas pleasure horses in full work have a reported prevalence of approximately 60%. Emerging diagnostic tests which could obviate the need for gastroscopy are introduced and current recommendations for treatment are summarised, focussing on proton pump inhibitors, in particular omeprazole, administered orally. The oral administration of omeprazole has been shown to be effective in both treating horses with gastric ulceration and at preventing re-occurrence whilst the horses are in training, provided that daily dosing is maintained.

The prevalence of gastric ulceration in racehorses in New Zealand is similar to that reported elsewhere for horses in active training for racing. Access to pasture for some or all of the day did not appear to be protective.

Characteristic changes in cytograms produced by the Advia 120 allowed recognition of artifactual changes in stored equine blood samples. These changes were less pronounced in samples stored at 24 degrees C than at 4 degrees C.