Can Locomotion Asymmetry in Young Trotters Predict Early Race Performance?

Abstract

IntroductionLameness is the most common health problem of racehorses and may affect both welfare and performance. The aim of this study was to investigate if locomotion asymmetry in a group of young horses was related to delayed qualification for races.MethodsLocomotion asymmetry was measured every 1–3 months with a wireless inertial sensor based lameness evaluation system in 16 horses fourteen times between September of the year they were 1‐year olds and May of the year they were 3‐year olds. As 3‐year‐olds they passed their qualification race and after this, two subgroups were created for the study based on whether they passed their qualification race before June 21st (early group, n = 6) or after September 19th (late group, n = 6). The groups were compared with respect to the differences in vertical head (forelimbs) and pelvis (hindlimbs) movement (as measured by the Lameness Locator, Equinosis) during each stride cycle at trot. The vector sums (VS) of maximum and minimum difference from each sensor were calculated and used for statistical analyses. ANOVA (Proc mixed model including individual {random}, date and group) was used to analyse differences between groups.ResultsThe late group had higher VS for forelimbs (16.0 ± 1.0) than the early group (12.6 ± 1.0) (P = 0.04) in total over the whole period. The VS for hind limbs did not differ between groups.ConclusionsFront limb locomotion asymmetry in young horses in training is associated with delayed qualification for races. However, further studies are warranted to investigate causality.Ethical Animal ResearchThe study was approved by the local ethics committee in Umeå, Sweden. Explicit owner informed consent for participation in this study is not stated. Sources of funding: Swedish University of Agricultural Sciences, the Swedish National Trotting School, Wången, the Swedish Trotting Association, The Swedish Horse Council Foundation, the Swedish Horse Racing Totalisator Board (ATG), Trioplast AB and Dow Chemicals. Competing interests: none.