CORTISOL-LEVELS IN RED DEER (CERVUS-ELAPHUS) AND FALLOW DEER (DAMA-DAMA) AFTER AN ACUTE ACTH ADMINISTRATION

Cortisol levels were determined in seven 2.5-year-old male red deer (Cervus elaphus) and 8 yearling male fallow deer (Dama dama) after an acute intramuscular injection of 0, 10, or 40 international units (IU) of ACTH, administered in June, July, or August. In both species a highly significant increase in cortisol concentration was observed within the first hour after both doses of ACTH. At the end of the rapid cortisol elevation (60 min post ACTH) the response in bath species was equal for the 10 and 40 IU doses. Average pretreatment levels were around 1-2 mu g/100 mt; peak levels registered in red deer were around 10 mu g/100 mt, and in fallow deer maximal concentrations reached around 8 mu g/100 mt. Although all deer responded to ACTH, strong interindividual differences in intensity of cortisol elevation were detected. The extent of increase of blood cortisol levels in response to ACTH appears to be an evolutionary adaptation of various cervid species to their respective environmental conditions.