title: The effect of an equatorial light environment on reproduction in sheep. I. The breeding season.
mesh_terms: D000818:Animals; D001947:Breeding; D004971:Estrus; D005260:Female; D008027:Light; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D012098:Reproduction; D012621:Seasons; D012756:Sheep / Q000502:physiology*
chemical_list: D011374:Progesterone