EFFECTS OF AN ANTIANDROGEN TREATMENT ON MORPHOLOGICAL CHARACTERS AND PHYSIOLOGICAL FUNCTIONS OF MALE FALLOW DEER (DAMA-DAMA L)

From mid-April to late November, i.e., during antler growth phase and main breeding season, a group of four (later three) male fallow deer w as treated with increasing doses of the antiandrogen cyproterone aceta te (CA). Throughout the treatment period, plasma testosterone levels o f the bucks were either undetectable or only slightly above the detect ion limit of 0.1 ng/ml. In marked contrast to controls, testicular vol umes and neck girths of the CA treated bucks were basal during the app lication period, proving the strong antigonadotropic effect of CA (tes ticular volume) and the absence of androgen action at the normal targe t organs (neck girths), respectively. Antler growth in the CA treated bucks occurred during the normal time span for fallow deer and the ant lers produced were of species specific shape. From this it is conclude d that in fallow deer, onset, duration, and termination of antler grow th are independent of androgen action. Velvet shedding in the CA treat ed bucks however did not occur at the normal time (late August/early S eptember), but was postponed until late December/early January, i.e., about 5 weeks after the termination of CA application. Activity of alk aline phosphatase in the experimental animals increased during the ant ler growth phase, but was markedly lower than in controls. Maximum bod y weight in the CA treated bucks was reached already in June, i.e., ab out 3 months prior to controls. Furthermore, the rut associated, drast ic decline in body weight observed in controls did not occur in the ex perimental animals. (C) 1993 Wiley-Liss, Inc.