[Variations in the plasma concentration of prolactin, LH and FSH and in testicular activity during the first year of life in the roe deer (Capreolus capreolus L.)].

Plasma prolactin, LH, FSH, testosterone patterns, and spermatogenic activity were determined during the first year of life in roe deer. A high gonadotrophic activity was observed a few months after birth, in autumn, along with an increase of testis volume and spermatogenic activity. Some spermatozoa could be seen in seminiferous tubules in December. A second increase of pituitary gonadotrophic activity appears in early spring when testicular volumes comparable to the adult are achieved. The first period of gonadotrophic activity coincides with the autumnal decrease in photoperiod, whereas the second coincides with the progressive increase in day length. It is suggested that the precocious LH and FSH release induces the first pubertal testicular activity.