The aim of this study was to evaluate and compare the plasmatic lactate and glucose, serum insulin and cortisol in healthy non pregnant mares treated with: polyethylene glycol 3350 (PEG); or polyethylene glycol 3350 associated with Ringer lactate (PEG+RL), or enteral polionic isotonic solution (EPIS); or enteral polionic isotonic solution associated with Ringer lactate (EPIS+RL); or sodium chloride solution 0.9% (NaCl). Laboratory tests were carried out in the following moments: immediately before the start of treatment (T0h), at six hours (T6h) and at the end of treatment (T12h), with 24 (T24h) and 48 hours (T48h) after T0h. The lactate did not change significantly. There was a slight increase in glucose and insulin values in EPIS caused by the presence of maltodextrin. Cortisol increased in animals from all treatments, but this increase was lower in the animals in EPIS. It is concluded that the treatments did not alter the values of glucose, lactate and insulin in healthy mares and the enteral hydration in continuous flow done in the EPIS treatment caused less stress to the animals.
equine; hydration; polyethylene glycol