Fertilizing rabbit spermatozoa are not selected as a special population by the female tract.
The survival of rabbit embryos from eggs fertilized by spermatozoa passing naturally from the vagina to the ampulla of the oviduct was compared with that of eggs fertilized by 'unselected' spermatozoa inseminated directly into the oviduct. After their transfer at the 2-cell stage to recipient does, embryos derived from fertilization with 'unselected' spermatozoa (57%) survived as well as those eggs fertilized by the natural 'selected' ampullary population (62%). Spermatozoa taken from the uterus 4 h post coitum ('selected' by virtue of having passed the cervix) were not competitively superior to an equal number of spermatozoa from the ejaculate of the same buck. The results do not support the suggestion that the reproductive tract of the female rabbit selects a genetically elite subpopulation of spermatozoa from the ejaculate.
D000818:Animals; D005187:Fallopian Tubes / Q000502:physiology; D005260:Female; D005306:Fertilization; D005836:Genitalia, Female / Q000502:physiology*; D007315:Insemination, Artificial; D008297:Male; D011817:Rabbits / Q000502:physiology*; D013083:Sperm Transport; D013094:Spermatozoa / Q000502:physiology*; D014599:Uterus / Q000502:physiology; D014621:Vagina / Q000502:physiology