Prejudicial findings regarding suitability for intended purpose during pre-purchase examinations in a mixed horse population-A retrospective observational study in the United Kingdom.

Abstract: Pre-purchase examinations (PPEs) are performed for prospective purchasers of horses to identify prejudicial findings that could make animals unsuitable for an intended use. Although this examination process is often standardised, PPEs remain, in large parts, a subjective procedure. In the United Kingdom, PPEs generally consist of either a two stage (two stage vetting [2SV], i.e., general physical examination at rest and basic trot in-hand) or a five stage-examination (five stage vetting [5SV], i.e., general physical exam at rest and after exercise, lameness evaluation including strenuous exercise with re-evaluation after a period of recovery). Objective: To identify the proportion of PPEs with prejudicial findings in a mixed horse population in the United Kingdom and to determine those findings. Methods: Retrospective observational study. Methods: PPE certificates from three first opinion equine practices were reviewed. Data collected included practice identity, examination format (i.e., 2SV or 5SV), PPE outcome, radiographs obtained (yes/no), purchase price, animal signalment, intended use and prejudicial PPE findings, if indicated. Prejudicial findings were grouped in 10 subcategories. Descriptive statistics were obtained for all parameters. Non-normally distributed numeric data between groups were compared using Wilcoxon rank-sum test. Categorical data were compared between groups using Pearson's chi-squared test or Fisher's exact test. Results: Overall, 133 pre-purchase examination certificates were analysed. Seventy-six horses (57.1%) had prejudicial findings: Sixty-one (68.5%) horses undergoing 5SV and 15 (34.1%) of horses undergoing 2SV. Most horses had lameness as the primary prejudicial finding. Horses with a higher purchase price were more likely to undergo 5SV, undergo pre-purchase radiography, and were more likely to have prejudicial findings identified. Conclusions: Data were obtained retrospectively from PPE certificates from a single mixed horse population and different results may have been obtained by analysing a larger number of animals or PPEs of horses intended for different uses, from different geographical regions or undergoing a different PPE format. The level of competition in the intended discipline for horses was not recorded. Analysed data were limited to the information recorded on the PPE certificates, and the original radiographs, ultrasonography images and other additional diagnostic data were not reviewed. Conclusions: Lameness was the most common prejudicial PPE finding. More expensive horses were more likely to undergo a 5SV, have pre-purchase radiographs obtained and have prejudicial findings identified. These results may help inform prospective studies examining the merits of 5SV versus 2SV formats and the value of inclusion of additional diagnostic imaging in PPEs in the general horse population.