We evaluated the behavior of osmolality, anion gap, pH and measurable plasma ions of 14 Purebred Arabian horses, 9 males and 5 females, finalists in an endurance race of 90 km. In order to achieve this, we collected venous blood samples twice, at rest and after prolonged exercise, in order to measure the interest variables. The results allowed to observe that from the rest an increase with significant difference in the values of Hct, PPT and AG, suggesting loss of fluids and slight dehydration. The pH and the H+ ion almost had no changes, indicating absence of metabolic disorders. Reductions, with significant difference, were verified for the ions Cl-, HCO³-, K+, Ca++, as well as BE. These data suggest that the type of exercise to which the animals were submitted was consistent with the athletic ability and that supplementation during the competition contributed to minimize such losses.
equine; exercise physiology; endurance; hydroelectrolytic balance