Exercise-induced changes in blood composition of racing reindeer (Rangifer tarandus tarandus L.)

The responses to near-maximal exercise before and after the training and racing season were examined in reindeer. The reindeer were tested when pulling a driver at a speed of 11-12 m/s for 600 m. The lactate responses were higher before than after training. Similarly, the accumulation of uric acid, a breakdown product of ATP, became attenuated after training. The serum concentrations of nonesterified fatty acids decreased or did not change after exercise, although an increase in the glycerol concentration indicates activation of lipolysis. The concentration of alanine increased after both tests, and at rest the concentrations of several amino acids, e.g., glutamine, isoleucine, and tyrosine, were higher and the concentrations of serum protein and urea were lower during spring than at the beginning of the training period. It can be concluded that the carbohydrate metabolism of the reindeer responds to exercise and training similarly to that in other athletic species, but further studies are needed to explain the observed changes in lipid and protein metabolites.