Show-jumping horses: hematology, biochemistry and kinematics of horses in show-jumping competition

ABSTRACT: This study evaluated the hematological, blood biochemistry variables and linear kinematic characteristics of horses in show-jumping competition. Eighteen Brazilian Sport Horses, 12 males and 6 females, were used in sports activities and participated in competitions in the Amateur category. The horses participated in a show-jumping competition with 11 obstacles. Based on the results of the competition, the horses were separated into three performance groups: best, medium and lowest performance, with six animals each. The experimental design was completely randomized with three performance groups of horses in the treatments. The hematocrit and blood concentrations of lactate, total protein, glucose, uric acid, creatine kinase (CK), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) were evaluated before and after the competition. The kinematic evaluation of the horses’ jumping was performed on the same obstacle, and the footage was recorded with a 25Hz video camera. The horses received 19 reflective markers and videos were analyzed with the Simi Reality Motion Systems® software. Plasma uric acid concentrations differed among horses in the performance groups (P < 0.05). The best-performing horses had higher uric acid concentrations than the worst-performing horses (P < 0.05). The uric acid concentrations reduced 10 and 30 minutes after the competition compared to rest. The hematocrit and plasma concentrations of lactate, total protein, CK, AST and LDH did not differ between groups of horses (P > 0.05), but differed between the times of blood sample collection (P < 0.05). The hematocrit and concentrations of lactate and total plasma protein were higher, while glucose concentration was lower immediately after competition. The horses with lowest performance had higher AST concentrations 24 hours after competition compared to rest (P < 0.05). There was no variation in CK concentrations in horses of the performance groups or between the different times of competition (P > 0.05). There was no difference in the values of kinematic variables of jumping horses between performance groups (P > 0.05). It can be concluded that, except for uric acid, the other hematological and blood biochemistry variables did not show any changes in the horses in the performance groups, but rather according to the time of blood collection.