Analysis of acid–base balance as well as hematological and biochemical parameters in horses of combined driving discipline

Abstract

Abstract. The aim of this study was to evaluate the effect of training on hematological and biochemical blood indices and acid–base balance as well as to attempt an assessment of the degree of driving horses' training based on examined parameters during the training cycle. The study was conducted on eight Polish Halfbred driving horses (aged 6–12 years). Each four-horse harness included two geldings and two mares. Blood was collected before and directly after training as well as after a 30 min recovery period. Blood samples were analyzed for hematological and biochemical parameters, as well as acid–base balance and glutathione peroxidase activity. The data were processed using a general linear model (ANOVA) procedure in Statistica v10. A significant (P < 0.01) post-exercise increase in heart rate and respiratory rate was noted. Changes (P < 0.01) in red blood cells (RBC), hemoglobin (HGB), glucose (GLU) and nonesterified fatty acids (NEFA) were observed after exercise. Correctness of the exercises affects the rate of recovery to rest values. The fastest recovery to the values of the rest period was noted in the case of RBC, HGB, LYM (lymphocytes), TCO2 (total carbon dioxide), HCO3− (bicarbonate concentration), GLU and NEFA. Training load did not cause acid–base balance disturbance, with visible compensation during the recovery period (increase in HCO3− and extracellular base excess (BE)). Changes in GPx activity were not confirmed statistically; however an increasing tendency was observed after training. Long-term exercises of driving horses cause significant lipomobilization. This study enables an evaluation and comparison of physical preparation to effort and intensity of driving horses' training. In the case of driving horses' training, there is a need to accept lower lactic acid (LA) (< 4 mmol L−1) values in aerobic–anaerobic threshold interpretation.