CHANGES IN PHYSIOLOGICAL VARIABLES IN HORSES COMPETING IN A COMBINED TEST

Abstract

Heart rate, respiratory rate, rectal temperature, glucose, plasma lactate, pack cell volume, total proteins, albumin, urea, creatinine, aspartate aminotransferase, creatine kinase, lactate dehydrogenase, gamma glutamyl transferase, alkaline fosfatase, calcium and phosphorus, in a group of horses, were studied at rest, at five, thirty and sixty minutes from the end of a Combined Test, beginning with eight jumps in a sand ring, on a distance of 240 meters, at a speed of 400 meters per minute and a cross country course with fifteen jumps, on a distance of 3.100 meters, at a speed of 690 meters per minute. The event took place in May (Southern Hemisphere) with a temperature of 14° C and 88 % of humidity. All variables were elevated at five minutes, recovering at thirty minutes, except from respiratory rate and plasma lactate, both of witch remained elevate at thirty and sixty minutes, due to the metabolic acidosis, char- acteristic of this type of exercise. Glucose showed no changes at any time and calcium descended at thirty minutes. In the conditions of this Combined Test, all the variables measured in this experience, returned to physiological values at times considered acceptable for well trained horses, although there were significant differ- ences (p<0.05) with rest values.