Edwards S A A, Atkinson P C, Satake N, Boe-Hansen G, McGowan M R
School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
Anim Reprod Sci. 2014 Jul;148(1-2):18-25. doi: 10.1016/j.anireprosci.2014.05.005. Epub 2014 May 16.
The objective was to investigate the ovarian response of Brahman heifers to two modified ovulation synchronisation protocols developed to increase the proportion of normal synchronous ovulations. Experiment 1 characterised the growth of the ovulatory follicle in heifers (n=19) treated with an intravaginal progesterone releasing device (IPRD) and oestradiol benzoate (ODB), to determine the optimal time to induce ovulation. Using the findings from Experiment 1, Experiment 2 investigated the effect of reducing the duration of IPRD insertion and increasing the interval from IPRD removal to ODB treatment (modified protocol 1 - OPO-6; n=20), and omitting ODB treatment at the time of IPRD insertion (modified protocol 2 - PO-6; n=20). An IPRD (0.78 g progesterone) was inserted at Day 0 (OPO-8) or Day 2 (OPO-6 and PO-6) and all heifers also received 1 mg ODB i.m. Day 8: IPRD removed + 500 μg cloprostenol i.m. At 24 h (OPO-8) and 36 h (OPO-6 and PO-6) post IPRD removal: 1 mg ODB i.m. Fixed-time AI (FTAI) occurred at 54 h for OPO-8 and 72 h for OPO-6 and PO-6, post IPRD removal. After IPRD treatment all OPO-6 and OPO-8 heifers initiated a new follicular wave whereas 25% of PO-6 heifers failed. Diameter of the dominant follicle was larger at FTAI in the PO-6 (11.34 ± 0.50 mm) compared to the OPO-8 protocol (9.74 ± 0.51 mm; P<0.05), but similar to the OPO-6 protocol (10.52 ± 0.51 mm). Proportion of ovulations occurring 12 h prior and 24 h post FTAI was similar for the PO-6 (80%) and OPO-6 (75%) protocols but numerically lower in the OPO-8 heifers (60%). The apparent improvement in ovarian response in heifers treated with the modified protocols needs to be confirmed in larger field studies.
目的是研究婆罗门小母牛对两种改良排卵同步方案的卵巢反应，这两种方案旨在提高正常同步排卵的比例。实验1对接受阴道内孕酮释放装置（IPRD）和苯甲酸雌二醇（ODB）处理的小母牛（n = 19）中排卵卵泡的生长进行了特征描述，以确定诱导排卵的最佳时间。利用实验1的结果，实验2研究了缩短IPRD插入时间并增加从IPRD取出到ODB处理的间隔时间（改良方案1 - OPO - 6；n = 20），以及在IPRD插入时省略ODB处理（改良方案2 - PO - 6；n = 20）的效果。在第0天（OPO - 8）或第2天（OPO - 6和PO - 6）插入一个IPRD（0.78 g孕酮），所有小母牛还在肌肉注射1 mg ODB。第8天：取出IPRD + 肌肉注射500 μg氯前列醇。在取出IPRD后24小时（OPO - 8）和36小时（OPO - 6和PO - 6）：肌肉注射1 mg ODB。定时人工授精（FTAI）在取出IPRD后，OPO - 8为54小时，OPO - 6和PO - 6为72小时进行。IPRD处理后，所有OPO - 6和OPO - 8小母牛开始了新的卵泡波，而25%的PO - 6小母牛失败。与OPO - 8方案（9.74±0.51 mm；P<0.05）相比，PO - 6方案在FTAI时优势卵泡直径更大（11.34±0.50 mm），但与OPO - 6方案（10.52±0.51 mm）相似。PO - 6（80%）和OPO - 6（75%）方案在FTAI前12小时和后24小时发生排卵的比例相似，但OPO - 8小母牛在数值上较低（60%）。改良方案处理的小母牛卵巢反应的明显改善需要在更大规模的田间研究中得到证实。
