Escuela de Medicina Veterinaria, Facultad de Recursos Naturales, Universidad Católica de Temuco, Chile.
Anim Reprod Sci. 2011 Nov;129(1-2):1-6. doi: 10.1016/j.anireprosci.2011.10.001. Epub 2011 Oct 7.
This study was conducted to determine the use of repeated transvaginal ultrasound-guided cumulus oocyte complex (COC) aspiration on COC recovery rate, in vitro embryo production (IVP) and subsequent pregnancy rates in Holstein Friesian (HF) and Aberdeen Angus (AA) cows (Experiment 1), and in pregnant and non-pregnant Holstein Friesian cows (Experiment 2). Cycling, non-pregnant HF (n=17) and AA (n=32) cows with 40-70 days postpartum, between 3 and 5 years of age were used in the Experiment 1. All cows were submitted to repeated transvaginal ultrasound-guided COC aspiration twice a week for 5-7 weeks. Cumulus ooctye complexes (COC) were in vitro matured, fertilized and cultured for 8 days. An overall of 100 and 350 embryos from HF and AA cows respectively were cryopreserved using a conventional slow freezing (Experiment 1). A total of 81 and 285 frozen-thawed embryos from HF and AA cows respectively were transferred to recipient cows. Pregnancy diagnosis was performed at 60 and 150 days of gestation using transrectal ultrasonography. In Experiment 2, cycling non-pregnant (n=9) and pregnant (n=8) HF cows were submitted to repeated ultrasound-guided COC aspiration and COC were in vitro matured, fertilized and cultured as in Experiment 1, except that embryos were cryopreserved but not thawed and transferred as described for Experiment 1. The results of this study indicate that COC recovery rate and blastocyts production are affected by the breed of the donor cow. The quality of blastocyts produced from both breed did not differ in terms of pregnancy and calving rates (Experiment 1). The physiologic state of pregnancy did not affect COC recovery rate and blastocysts production per donor/session (Experiment 2). The use of ultrasound-guided COC aspiration and IVP could be a powerful technique to improve the genetic of beef and dairy cattle managed under pasture-based conditions management in the southern Chile.
本研究旨在确定在荷斯坦弗里森（HF）和阿伯丁安格斯（AA）奶牛中（实验 1）以及在怀孕和非怀孕荷斯坦弗里森奶牛中（实验 2），经阴道超声引导下重复抽吸卵丘-卵母细胞复合物（COC）对 COC 回收率、体外胚胎生产（IVP）和随后妊娠率的影响。实验 1 中使用了处于发情周期、未怀孕的 HF（n=17）和 AA（n=32）奶牛，产后 40-70 天，年龄在 3 至 5 岁之间。所有奶牛均接受经阴道超声引导下重复 COC 抽吸，每周 2 次，持续 5-7 周。卵丘卵母细胞复合物（COC）在体外成熟、受精并培养 8 天。HF 和 AA 牛分别有 100 和 350 个胚胎被冷冻保存（实验 1）。HF 和 AA 牛分别有 81 和 285 个冷冻-解冻胚胎被转移到受体牛。使用经直肠超声在妊娠 60 和 150 天进行妊娠诊断。在实验 2 中，处于发情周期的非怀孕（n=9）和怀孕（n=8）HF 奶牛接受重复超声引导 COC 抽吸，COC 如实验 1 所述在体外成熟、受精和培养，但胚胎冷冻保存而不解冻和转移。本研究结果表明，COC 回收率和囊胚生产受供体牛品种的影响。两个品种的囊胚在妊娠和产犊率方面没有差异（实验 1）。怀孕的生理状态不影响每个供体/周期的 COC 回收率和囊胚生产（实验 2）。经阴道超声引导 COC 抽吸和 IVP 可成为一种强大的技术，可提高智利南部牧场管理下的肉牛和奶牛的遗传性能。
