From the Wild to the Uniform: Clinical and Echocardiographic Monitoring of Young Murgese Horses During the First Year of Training

Excessive training load can lead to maladaptation with measurable imbalances at the cardiovascular, endocrine, and hematological levels. The first aim of this study was to evaluate conventional and advanced echocardiographic parameters in young Murgese horses during training over one year, in order to assess the effect of training on cardiac dimensions and function. The second aim was to assess the general conditions and to monitor work adaptation indices through clinical examinations and hematobiochemical tests. Young Murgese horses intended for training and working in the Carabinieri Army Forces were evaluated at four different training stages: at the stabling phase-enrolling (T0); at the end of the desensitization and ground-work phase, shortly before being ridden (T1); in the midst of ridden athletic preparation (T2); and at the end of the training period (T3-one year of training). Clinical, echocardiographic and haemato-biochemical exams were performed; data were analyzed over time by Friedman and Wilcoxon test. Bonferroni corrections were applied. A significant increase in ejection fraction (EF%) and shortening fraction (FS%) was documented between T0 and T1 (p = 0.016, p = 0.011, respectively). Moreover, left atrial dimensions increased between T0 and T2 (p = 0.021) and between T1 and T2 (p = 0.028). No additional statistically significant changes were observed for other echocardiographic parameters. Regarding clinical and laboratory variables, significant differences were noted for HCT, Hgb, RBC, WBC, lymphocytes, AST, urea, and lactate (p < 0.05). Our echocardiographic and hematobiochemical findings suggest that, in Murgese horses, training may have an impact on the cardiovascular system and on the metabolic axis during the athletic preparation phase. Maturation and other time-dependent factors could not be excluded as co-factors of the observed longitudinal changes.