Relationship between antler development and plasma androgen concentrations in adult roe deer (Capreolus capreolus).

Four male deer (4-5 years old), living in normal park conditions, were captured every 2 weeks in the year to study annual variations in androgen levels and the relationship between testicular activity and the antler cycle. Data were also obtained from 77 wild adult males (greater than 3 years old) caught in the forest. Plasma androgen concentrations rose briefly in April and markedly in August; the high values in August corresponded with the breeding period. From the time of casting to maximum growth was about 60 days; mineralization of the antlers then lasted for 45 days only. The mineralization phase of antler growth corresponded to the reactivation of testicular function in late January (0.43 +/- 0.16 to 1.99 +/- 0.42 ng androgen/ml, N = 4).