title: A comparison between the pregnancy rates of heifers inseminated once or twice after progestin treatment.
mesh_terms: D000818:Animals; D002417:Cattle / Q000502:physiology*; D004958:Estradiol / Q000494:pharmacology; D005260:Female; D007315:Insemination, Artificial / Q000662:veterinary*; D008297:Male; D009652:Norpregnenes / Q000494:pharmacology; D010060:Ovulation / Q000187:drug effects; D011247:Pregnancy; D011270:Pregnancy, Animal; D011282:Pregnenediones / Q000494:pharmacology*; D045167:Progesterone Congeners / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D009652:Norpregnenes; D011282:Pregnenediones; D045167:Progesterone Congeners; D004958:Estradiol