Fig. 1

Schematic diagram of the synchronization of ovulation protocol in suckled anestrous beef cows. EB = 2 mg of estradiol benzoate; P4 = progesterone; P4 insert = previously used intravaginal P4 insert containing 1.0 g of P4; GnRH = 100 mg of gonadorelin; ECP = 1 mg of estradiol cypionate; eCG = 400 IU of equine chorionic gonadotropin; PGF2α = 0.25 mg of cloprostenol; US = ultrasound examination; BS = blood sample. Cows from ECP group received ECP and cows from eCG group received eCG, while cows from CON did not receive any further treatment and cows from ECP + ECG received both treatments