Effects of injected ovarian steroids on reproductive patterns and performance in post-partum mares.
Treatment of foaling mares with 150 mg progesterone and 10 mg oestradiol daily beginning within 12 h of parturition resulted in a delay of ovulation (15.6 +/- 2.6 days compared with 10.3 +/- 2.4 days in untreated mares). When mares were mated after this 5.3-day delay there was no advantage in reproductive performance over that of mares mated according to a conventional management system. Gonadotrophin secretion was inhibited during treatment but the following secretory patterns were similar to those of normal oestrous periods.
D000818:Animals; D004958:Estradiol / Q000494:pharmacology*; D004971:Estrus / Q000187:drug effects; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006736:Horses / Q000502:physiology*; D007986:Luteinizing Hormone / Q000097:blood; D010060:Ovulation; D011247:Pregnancy; D011374:Progesterone / Q000494:pharmacology*; D011863:Radioimmunoassay; D012098:Reproduction / Q000187:drug effects*
D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone