title: The fertilizing capacity of epididymal spermatozoa in relation to age, body weight and the onset of sexual maturity in the golden hamster.
abstract: Experiments with prepubertal hamsters were undertaken to determine if the appearance of spermatozoa with fertilizing capacity in the cauda epididymidis is related to age and/or body weight and whether the development of sperm function coincides with complete maturation of the mating behaviour pattern. At Week 6 after birth, intrauterine insemination of comparable numbers of spermatozoa showed that fertilizing capacity was related to body weight and not to age or seminal vesicular fructose concentration. In contrast to the low fertilization rate produced by spermatozoa from males weighing 80 g at Week 6 after birth, spermatozoa from 80-g males at Week 7 showed normal fertilizing capacity. Only 50% of 7-week-old males weighing 100-110 g produced fertile matings whereas all matings were fertile with males weighing 135 g and with males weighing 100 to 110 g that had received 7 consecutive daily injections of 50 mug testosterone beginning at Week 6 after birth. Comparison of sperm numbers in the cauda epididymidis and ductus deferens after mating at Week 7 showed that males which produced sterile matings were unable to terminate intromission with normal ejaculation of spermatozoa.
mesh_terms: D000375:Aging; D000818:Animals; D001835:Body Weight; D002452:Cell Count; D006224:Cricetinae; D004542:Ejaculation; D004822:Epididymis; D005260:Female; D005298:Fertility / Q000187:drug effects; D005632:Fructose / Q000378:metabolism; D008297:Male; D009929:Organ Size; D012669:Seminal Vesicles / Q000378:metabolism; D012741:Sexual Maturation; D013094:Spermatozoa / Q000502:physiology*; D013737:Testis; D013739:Testosterone / Q000494:pharmacology
chemical_list: D005632:Fructose; D013739:Testosterone