Abstract
An ultrastructural study of spermiogenesis was carried out in adult hypophysectomized rams supplemented with testosterone at a dose which induced a normal or excessive (1 to 3) concentration of the steroid within the rete testis fluid (Monet-Kuntz et al., '76). Most of the spermatids from 15- or 20-day treated animals displayed a normal nuclear appearance but possessed acrosomes with morphological abnormalities. The process of acrosome formation as well as its binding to the nucleus was severely impaired in young spermatids, whereas only morphological changes of the acrosomes were seen in old spermatids. The suggestion is made that acrosome development is under the control of endocrine-dependent cellular events occurring before the beginning of spermiogenesis, possibly via Sertoli cell/germ cell interactions. The spermatids from hypophysectomized rams supplemented with testosterone for 40 days were normal in appearance but reduced in number. The Sertoli cell ultrastructure differed for the two durations of treatment.