摘要
The underlying theme of this study involved the evaluation of the dilatory effects of prostaglandin E2 on the ovine cervix and thus the assessment of its potential applicability to transcervical artificial insemination (TCAI) in ewes. A novel method of prostaglandin E2 administration (controlled slow-release vaginal inserts) was examined, and the practical implications of this approach including cervical penetrability and posttreatment pregnancy rates were evaluated. The Guelph method of TCAI was performed during the seasonal anestrus (n = 40) and the breeding season (n = 40) on multiparous Rideau Arcott × Polled Dorset ewes, with or without the pretreatment with Cervidil (for a duration of 12 hours or 24 hours before TCAI). Cervical penetration rates averaged 82.5% (66 of 80), and they varied neither (P > 0.05) between the two seasons nor between Cervidil-treated ewes and their respective controls. Cervidil priming significantly reduced the total time required for TCAI during the breeding season in comparison with controls (54 vs. 98 seconds), especially after the 24-hour exposure (38 vs. 108 seconds). The time taken to traverse the uterine cervix was negatively correlated (P < 0.05) with the breed (percentage of Rideau Arcott genotype) and lifetime lamb production in seasonally anestrous ewes. Four out of 36 (11%) successfully penetrated ewes in the breeding season (three ewes allocated to the 12-hour control group and one ewe that had received Cervidil for 12 hours) became pregnant and carried the lambs to term. Vaginal mucus impedance at TCAI was significantly and positively correlated with the total time required to complete the procedure in cyclic ewes, and the negative correlation between vaginal mucus impedance and total time values at the time of controlled intravaginal drug release device removal approached to significance in anestrous ewes. The present results indicate a moderate benefit of using Cervidil for inducing cervical dilation before TCAI in ewes, mainly in the breeding season. The specific reason(s) for impaired fertility after the TCAI using frozen–thawed ram semen remains to be elucidated.
摘要译文
涉及前列腺素E 2对绵羊宫颈拖拉影响母羊的评价，因而其潜在适用性的评估宫颈人工授精（TCAI）了检查前列腺素E 2管理的新方法（受控缓释阴道插入），而这种做法的实际影响，包括颈椎穿透性和治疗后的妊娠率评估繁殖季节（N \x3d 40）在多子里多Arcott×轮询赛特母羊季节性乏情期间执行TCAI的方法圭尔夫（N \x3d 40）和，用或不用Cervidil预处理（为12小时或24小时TCAI之前的持续时间）颈椎渗透率平均为825（80 66），和它们改变既不（P05）在两个赛季之间也Cervidil处理母羊和它们各自的对照组之间Cervidil吸显著降低（38与对照组（54 vs98秒），特别是24小时曝光后比较在繁殖季节为TCAI所需的总时间与108秒）穿越宫颈所花费的时间呈负相关（P 005）与品种（丽都Arcott基因型的百分比），终身羊肉产量季节性休情母羊uccessfully渗透在繁殖季节母羊（三级母羊分配给已收到Cervidil 12小时12小时对照组和一个母羊）就怀孕，携带的羔羊项在TCAI阴道粘液阻抗与完成在环状母羊的过程所需的总时间显著和正相关，并控制在阴道内药物释放装置去除时阴道黏液的阻抗和总时间值之间的负相关关系走近在休情母羊意义目前的结果表明使用Cervidil在母羊TCAI之前诱发宫颈扩张适度的好处，主要是在繁殖季节用冷冻鈥搕hawed公羊精液的TCAI后，生育能力受损的具体原因（S）仍有待澄清
Pawel M. Bartlewski; Ivanka B.R. Candappa. Assessing the usefulness of prostaglandin E2 (Cervidil) for transcervical artificial insemination in ewes[J]. Theriogenology, 2015,84(9): 1594–1602