Shi Junsong, Zhou Rong, Luo Lvhua, Mai Ranbiao, Zeng Haiyu, He Xiaoyan, Liu Dewu, Zeng Fang, Cai Gengyuan, Ji Hongmei, Tang Fei, Wang Qinglai, Wu Zhenfang, Li Zicong
National Engineering Research Center for Breeding Swine Industry, South China Agricultural University and Guangdong Wen's Foodstuff Group, Guangdong, PR China.
National Engineering Research Center for Breeding Swine Industry, South China Agricultural University and Guangdong Wen's Foodstuff Group, Guangdong, PR China; College of Animal Science, South China Agricultural University, Guangdong, PR China.
Anim Reprod Sci. 2015 Mar;154:121-7. doi: 10.1016/j.anireprosci.2015.01.006. Epub 2015 Jan 28.
The somatic cell nuclear transfer (SCNT) technique could be used to produce genetically superior or genetically engineered cloned pigs that have wide application in agriculture and bioscience research. However, the efficiency of porcine SCNT currently is very low. Embryo transfer (ET) is a key step for the success of SCNT. In this study, the effects of several ET-related factors, including cloned embryo culture time, recipient's ovulation status, co-transferred helper embryos and ET position, on the success rate of pig cloning were investigated. The results indicated that transfer of cloned embryos cultured for a longer time (22-24h vs. 4-6h) into pre-ovulatory sows decreased recipient's pregnancy rate and farrowing rate, and use of pre-ovulatory and post-ovulatory sows as recipients for SCNT embryos cultured for 22-24h resulted in a similar porcine SCNT efficiency. Use of insemination-produced in vivo fertilized, parthenogenetically activated and in vitro fertilized embryos as helper embryos to establish and/or maintain pregnancy of SCNT embryos recipients could not improve the success rate of porcine SCNT. Transfer of cloned embryos into double oviducts of surrogates significantly increased pregnancy rate as well as farrowing rate of recipients, and the developmental rate of transferred cloned embryos, as compared to unilateral oviduct transfer. This study provided useful information for optimization of the embryo handling and transfer protocol, which will help to improve the ability to generate cloned pigs.
体细胞核移植（SCNT）技术可用于生产在农业和生物科学研究中有广泛应用的遗传上更优良或经过基因工程改造的克隆猪。然而，目前猪SCNT的效率非常低。胚胎移植（ET）是SCNT成功的关键步骤。在本研究中，研究了几个与ET相关的因素，包括克隆胚胎培养时间、受体的排卵状态、共同移植的辅助胚胎和ET位置，对猪克隆成功率的影响。结果表明，将培养时间较长（22 - 24小时与4 - 6小时相比）的克隆胚胎移植到排卵前的母猪中会降低受体的妊娠率和产仔率，并且将排卵前和排卵后的母猪用作培养22 - 24小时的SCNT胚胎的受体，猪SCNT效率相似。使用人工授精产生的体内受精、孤雌激活和体外受精胚胎作为辅助胚胎来建立和/或维持SCNT胚胎受体的妊娠，并不能提高猪SCNT的成功率。与单侧输卵管移植相比，将克隆胚胎移植到代孕母猪的双侧输卵管中可显著提高受体的妊娠率和产仔率，以及移植克隆胚胎的发育率。本研究为优化胚胎处理和移植方案提供了有用信息,这将有助于提高克隆猪的生产能力。
