EFFECTS OF CASTRATION AND TESTOSTERONE REPLACEMENT ON THE NUMBER OF SPERMATOZOA IN THE CAUDA EPIDIDYMIDIS OF HAMSTERS

To determine the effects of castration and testosterone replacement on sperm number in the cauda epididymides 35 hamsters were castrated after bilateral ligation of the corpus epididymides and unilateral vasectomy. Complete isolation of the cauda epididymides for 35 days in "ligated control" or castrated animals prevented the loss of spermatozoa from the region if the ductus deferens remained open. Sperm number decreased 60% 7 days after castration if both the corpus epididymides and ductus deferens were ligated. The method by which spermatozoa are removed from the cauda epididymides depends on whether circulating androgen is present. In the presence of testosterone spermatozoa are not removed in the cauda epididymides but pass into the ductus deferens.