Reproductive performance of early postpartum Holstein cows where oestrus was synchronised following chronic GnRH agonist treatment

Abstract

Objective The objectives of this study were: to compare the recovery of follicular development in early postpartum cows that had been treated for 7, 14 or 21 d with implants containing the GnRH agonist deslorelin; to evaluate the effectiveness of human chorionic gonadotrophin (hCG) for the induction of ovulation when a follicle was at least 10 mm in diameter following implant removal; and to compare final pregnancy rates for treated cows and untreated contemporaries. Procedure Within 3 d of calving Holstein cows were allocated to receive a single subcutaneous deslorelin implant to be left in place for either 7, 14 or 21 d, or to remain untreated as controls. Every deslorelin treated cow was ..