EFFECT OF STRESS ON STEROID HORMONE LEVELS IN RACEHORSES

Abstract
Cortisol and testosterone were measured by radioimmunoassay in plasma samples from race horses. None of 6 stressed male horses had low cortisol levels, but testosterone levels (0.81 .+-. 015 nmol/l) were significantly lower than in healthy horses (1.86 .+-. 0.31 nmol/l). Adrenocortical insufficiency apparently is not a common association of stress in race horses. The reduction in testosterone levels is probably a nonspecific response similar to that seen in other species.