Efektivitas pemberian GnRH pada sapi perah yang mengalami hipofungsi ovarium terhadap waktu timbulnya birahi dan angka kebuntingan

Ovarian hypofunction is a condition in which the follicles in the ovary can not develop due to lack of feed. It can affect the pituitary anterior, so the production of FSH and LH was low. GnRH can stimulate the pituitary anterior to produced FSH and LH. This study aimed to prove that GnRH injection in dairy cows with ovarian hypofunction can initiate estrus, followed by pregnancy. This study used 12 dairy cows with BCS ≥ 2.75, with anestrus due to ovarian hypofunction. All dairy cows were divided into two treatment groups, P1 injected with GnRH at a dose of 100 µg intramuscularly and P2 injected with GnRH at a dose of 300 µg intramuscularly. The results were analyzed using an independent t-test and Chi-Square test. The result showed that estrus rate of P1 and P2 were both 100%, meanwhile onset of estrus of P2 (53.83 ± 8.1 h) was shorter p <0.05) than P1 (74.17 ± 4.7 h). Both of P1 and P2 showed 100% pregnancy rate. It could be concluded that GnRH injection could initiate 100% estrus, and followed by 100% pregnancy in dairy cows with ovarian hypofunction.