Effect of estradiol cypionate and GnRH treatment on plasma estradiol-17β concentrations, synchronization of ovulation and on pregnancy rates in suckled beef cows treated with FTAI based protocols

RODRIGUEZ AGUILAR, S.; VATER, A.; CALLEJAS, S.; USLENGHI, G.; CABODEVILA, J.

REPRODUCTION IN DOMESTIC ANIMALS (1990)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2016 vol. 51 p. 693 - 699

0936-6768

Two experiments were conducted to evaluate the effect of different ovulation treatments on E-17β plasma concentrations, synchronized ovulations and pregnancy rates. In Experiment 1, cows received on day 0 a progesterone intravaginal device (PID) with 1 g of progesterone (P4) plus 2 mg of estradiol benzoate (EB). En day 8, PID was removed and cows received 0.150 mg of D-Cloprostenol and were randomly assigned to a treatment group (n=10/treatment): 1 mg of estradiol cypionate (ECP) at PID removal, 1 mg of EB 24 h after PID removal, 10 µg of GnRH 48 h after PID removal, or 1 mg of ECP at PID removal plus 10 µg of GnRH 48 h later. Ultrasonographic examinations were performed to detect the dominant follicle and ovulation. GnRH-treated cows ovulated later (P