Aslan S, Arslanbas D, Beindorff N, Bollwein H
Department of Obstetrics and Gynaecology, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey.
Reprod Domest Anim. 2011 Oct;46(5):781-6. doi: 10.1111/j.1439-0531.2010.01741.x. Epub 2011 Jan 27.
The objective of this study was to compare the effects of gonadotropin-releasing hormone (GnRH) and human chorionic gonadotropin (hCG) on follicular blood flow (FBF) during the pre-ovulatory period and on luteal blood flow (LBF) during dioestrus in Holstein-Friesian heifers. Twelve animals were randomly divided into two groups and treated with either intramuscular injection of 100 μg GnRH or intravenous (IV) injection of 5000 IU hCG on Day 0 (oestrus, 48 h after administration of PGF(2α) ) to induce ovulation. Follicular size (FS), FBF and time of ovulation were recorded with colour Doppler sonography at 0, 1, 3, 6, 12 and 24 h after GnRH and hCG treatment. Luteal size (LS) and LBF were investigated on Day 9 and 12 after ovulation. Plasma samples were taken to determine total oestrogens (E(tot) ) and progesterone (P(4) ) after each examination. Ovulation occurred between 24 and 48 h after treatment in all animals. No difference (p > 0.05) was observed in FS between the two treatment groups. Follicular blood flow was higher in the hCG group than that was in GnRH group at 1 h after treatment (p < 0.01). Total oestrogens were also higher (p < 0.01) in the hCG group than GnRH group; however, this difference was only obvious at 12 h after treatment. No difference (p > 0.05) was observed in LS, LBF or P(4) levels on Day 9 and 12 between treatment groups. In conclusion, the results suggest that induction of ovulation with hCG and GnRH has a temporary effect on FBF and oestrogen levels while no effect on the size of corpora lutea, LBF and P(4) levels was observed.
本研究的目的是比较促性腺激素释放激素（GnRH）和人绒毛膜促性腺激素（hCG）对荷斯坦-弗里生小母牛排卵前期卵泡血流量（FBF）以及发情间期黄体血流量（LBF）的影响。将12头动物随机分为两组，在第0天（发情期，在注射前列腺素F2α（PGF2α）48小时后）分别进行肌肉注射100μg GnRH或静脉注射5000IU hCG以诱导排卵。在GnRH和hCG治疗后的0、1、3、6、12和24小时，用彩色多普勒超声记录卵泡大小（FS）、FBF和排卵时间。在排卵后的第9天和第12天检查黄体大小（LS）和LBF。每次检查后采集血浆样本以测定总雌激素（E(tot)）和孕酮（P4）。所有动物在治疗后24至48小时之间排卵。两个治疗组之间的FS没有差异（p>0.05）。治疗后1小时，hCG组的卵泡血流量高于GnRH组（p<0.01）。hCG组的总雌激素也高于GnRH组（p<0.01）；然而，这种差异仅在治疗后12小时明显。治疗组之间在第9天和第12天的LS、LBF或P4水平没有差异（p>0.05）。总之，结果表明，用hCG和GnRH诱导排卵对FBF和雌激素水平有暂时影响，而对黄体大小、LBF和P4水平没有影响。
