Prevalence of gastric ulcers and relationship to other parameters in Standardbred racehorses

Abstract

Gastric ulcer prevalence rate is reported to be 60-90% in racehorses. This study examined a population of 40 Standardbred horses in race training and assessed the relationship of ulcers to performance history and body condition score (BCS). Forty Standardbreds on two racing facilities in southern Michigan were examined during the last 2 weeks of December 2007 and the second week of January 2008. Age of horses (as of January 1) ranged from 3 to 12 years. Squamous epithelial ulcers were graded (0-4) using an established scoring system during gastroscopic examinations and BCS was recorded (1 to 9 scale). Trainers graded racing performance of each horse on a scale of A to F, with A being best. Horses were grouped according to gender, age, and BCS. Prevalence of ulcers was similar between facilities (50% and 56%) but the mean prevalence (52.5%) was lower than in previous reports. Ulcer score was not related to gender (P=0.84), age (P=0.72), BCS (P=0.64), or performance history (P=0.55). These findings suggest that commonly cited prevalence rates of ulcers may not be consistent for all populations of racehorses. Further, given that less than 20% of the horses examined had an ulcer score grade 2 or higher, the impact that ulcers have on performance may be overestimated in some equine populations. Finally, this study clearly demonstrates that a gastroscopic examination is necessary to determine presence of ulcers, rather than assuming their presence based on decreased performance or low body condition score.