Egg and embryos.
D000818:Animals; D002417:Cattle; D046508:Culture Techniques; D004622:Embryo, Mammalian; D004739:England; D004822:Epididymis / Q000502:physiology; D005260:Female; D005298:Fertility; D008297:Male; D008322:Mammals / Q000502:physiology; D051379:Mice; D010063:Ovum; D010312:Parthenogenesis; D013094:Spermatozoa; D013737:Testis / Q000502:physiology