title: Twinning in cattle.
mesh_terms: D000367:Age Factors; D000483:Alleles; D000818:Animals; D001947:Breeding; D002417:Cattle / Q000502:physiology*; D005260:Female; D005298:Fertility; D007178:Inbreeding; D008297:Male; D010060:Ovulation; D010063:Ovum / Q000637:transplantation; D011247:Pregnancy; D011272:Pregnancy, Multiple; D011374:Progesterone / Q000097:blood; D012621:Seasons; D012641:Selection, Genetic; D014184:Transplantation, Homologous
chemical_list: D011374:Progesterone