title: Concentration of steroids in bovine peripheral plasma during the oestrous cycle and the effect of betamethasone treatment.
abstract: Testosterone, oestradiol and progesterone were measured in peripheral plasma during the oestrous cycle of 6 heifers. Oestradiol and progesterone results confirmed earlier reports. Concentration of testosterone on the day of oestrus was 40+/-3 pg/ml (mean+/-S.E.M.), and two peaks were detected during the cycle, one 7 days before oestrus (1809+/-603 pg/ml) and the other (78+/- 7 pg/ml) on the day before the onset of oestrus. The concentration of progesterone declined in most cases 1 day after the maximum concentration of testosterone. Betamethasone treatment in 5 heifers extended luteal function by an average of 10 days: plasma androstenedione and oestradiol concentrations were unaltered; cortisol values were depressed for at least 16 days after treatment; testosterone concentrations were lowered by 13+/-2-4% during treatment, and except in one heifer the peak on Day -7 was abolished.
mesh_terms: D000311:Adrenal Glands / Q000502:physiology; D000735:Androstenedione / Q000097:blood; D000818:Animals; D001623:Betamethasone / Q000494:pharmacology*; D002417:Cattle / Q000502:physiology*; D003338:Corpus Luteum / Q000502:physiology; D004958:Estradiol / Q000097:blood; D004971:Estrus / Q000187:drug effects; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D013739:Testosterone / Q000097:blood
chemical_list: D012739:Gonadal Steroid Hormones; D013739:Testosterone; D000735:Androstenedione; D011374:Progesterone; D004958:Estradiol; D001623:Betamethasone; D006854:Hydrocortisone