The Response of Gonadotrophin Hormone at Different Dose on Time of Oestrus, the Pro le of Progesterone, Estrogen and Corpus Luteum of Ongole Crossed Cows

Abstract

Pregnant mare`s serum gonadotrophin (PMSG) was one of the gonadotrophin hormones which often used for improving the process of ovarian follicular development and formation of egg cells (oocytes). This study aims to determine the effect of inducing hormone gonadotrophin (PMSG) at different doses on the incidence of oestrus, estrogen and progesterone concentrations in the blood and the number of corpus luteum. The rresearch was conducted approximately four months at Indonesia Beef Cattle Research Station (IBCRS). The treatment of different PMSG dose, namely A = 1000 IU, B=1300 IU and C = 1600 IU. The implementation of gonadotrophin hormones began with the ovulation synchronization (ovsynch) using a combination of Gonadotropin Releasing Hormone (GnRH) and Prostaglandin (PGF) 2 alpha and PMSG. Completely randomized design was used in this reserch and collected data were analyzed one-way ANOVA. Variables measured were: time of oOestrus and mating, the concentration of the hormone estrogen, progesterone and the number of corpus luteum. The results showed that there was no difference between treatment of PMSG hormones or oestrus sign. PMSG treatment of the time of rst oestrus at different dose showed treatment A = 48.0 ± 50.3 hours, B = 45.6 ± 12.9 hours, C = 55.2 ± 48.1 hours. The second of oOestrus and mating evidence at different dose showed ttreatment A, B and C, were 67.2 ± 47.7; 69.6 ± 44.5 and 105.6 ± 68.1 hours, respectively. Effect of different doses of PMSG treatment was also not different on the concentration of estrogen and progesterone, namely, 16.4 ± 19.4 pg/ml and 7.2 ± 7.1 ng/ml (treatment A), 25.9 ± 17.4 pg/ml and 6.7 ± 5.8 ng/ml (treatment B), and 20.9 ± 20.0 pg/ml and 5.0 ± 6.4 ng/ml (treatment C), while the number of corpus luteum in ovarian right and left on the treatment, also showed no difference, namely 2.5 ± 2.4 ovaries (treatment A), 3.3 ± 1.4 ovaries (treatment B) and 2.1 ± 1.9 ovaries (treatment C). It can be concluded that the treatment of combination hormone of GnRH, PGF 2 alpha, PMSG and showed positive response to the appearance of oestrus and the number of corpus luteum in Ongole Crossed cows.