Economics of treatment with GnRH agonist 7-14 days after artificial insemination in repeat breeder lactating dairy cows

Abstract

This study looked at the effectiveness and financial benefits of treating repeat breeder (RB) dairy cows with the GnRH agonist gonadorelin 7-14 days after artificial insemination (AI). A total of 188 healthy dairy cows (2.4 ± 1.3 lactations) with an average milk yield of 42.1 ± 6.8 kg milk/day, at 179 ± 38.4 days in milk with 3.8 ± 1 AIs were divided into two groups, experimental (E group, n = 98) and control (C group, n = 90). The GnRH agonist gonadorelin was given 7-14 days after AI to the E group to evaluate the embryo survival in RB cows. The control group did not receive any treatment. Recorded pregnancy rates and cumulative pregnancy rates were superior in the E group (49% and 64.3%) compared with the C group (37.8% and 55.5%). The interaction between therapy and RB had a significant impact on the pregnancy rate and accessory corpus luteum (CL), according to a binary logistic regression study. The UW-DairyRepro$ decision support tool utilized in this experiment demonstrated that by implementing this approach, the net present value can be increased by US dollars (US$)30.2/RB cow/year. Thus, the single therapy with GnRH agonist gonadorelin between 7 and 14 days after AI enhanced the potential for a second CL in repeat-breeder pregnant cows, presumably favouring embryo survival.

Keywords: GnRH agonist; economic values; pregnancy rate; repeat breeder cows.