马卵母细胞孤雌激活与体细胞核移植技术

在马(Equus caballus)的繁殖和非繁殖季节,本研究探讨马扩展型(Ex)和紧凑型(Cp)卵丘-卵母细胞复合体(COCs)卵母细胞的孤雌激活效率。在繁殖季节,探讨马驹和成年马成纤维细胞核移植(SCNT)的成功率。孤雌激活实验结果显示,在繁殖季节,发育到2-细胞、4-细胞和桑椹胚的比例,扩展型(Ex)卵丘-卵母细胞复合体分别是52.8%(19/36)、38.9%(14/36)和5.6%(2/36),紧凑型(Cp)卵丘-卵母细胞复合体分别是47.9%(23/48)、33.3%(16/48)和6.2%(3/48)。在非繁殖季节,发育到2-细胞、4-细胞的比例,扩展型(Ex)分别是37.2%(16/43)和16.3%(7/43),紧凑型(Cp)的比例分别是35.1%(27/77)和11.7%(9/77),都没有获得桑椹胚。同一季节,扩展型(Ex)与紧凑型(Cp)胚胎发育的比率差异不显著(P 0.05),不同季节,两者差异显著(P 0.05)。体细胞核移植实验结果显示,以马驹成纤维细胞作为核供体细胞,胚胎发育到2-细胞、4～8细胞和桑椹胚的比例分别是41.5%(22/53)、33.9%(18/53)和15.1%(8/53),以成年马成纤维细胞作为核供体细胞,比例分别是38.9%(7/18)、22.2%(4/18),没有获得桑椹胚。综上所述,季节和卵丘-卵母细胞复合体(COCs)类型影响马卵母细胞孤雌激活的效率,不同核供体细胞影响克隆胚胎构建的成功率。

Parthenogenetic Oocyte Activation and Somatic Cell Nuclear Transfer in the Horse

This study investigated the parthenogenetic activation efficiency of oocytes from expanded (Ex) and compact (Cp) type of cumulus oocyte complexes (COCs) in the breeding and non-breeding seasons of horses (Equus caballus). The somatic cell nuclear transfer (SCNT) using fibroblasts from foals and adult horses was also studied. The results of parthenogenetic activation test showed that the proportions of Ex type oocytes developed to 2-cell, 4-cell and morula stages were 52.8% (19/36), 38.9% (14/36) and 5.6% (2/36) respectively, while those of Cp type oocytes were 47.9% (23/48), 33.3% (16/48) and 6.2% (3/48) respectively in the breeding season. The proportions of Ex type oocytes developed to 2-cell and 4-cell embryos were 37.2% (16/43) and 16.3% (7/43) respectively, while those of Cp type oocytes were 35.1% (27/77) and 11.7% (9/77) respectively, but morula stage embryos were not obtained in non-breeding season (Fig.4; Table 1). There was no significant difference in the rate of embryonic development between Ex and Cp (P > 0.05) groups in the same season, but there was significant difference between Ex and Cp groups in breeding and non-breeding seasons (P < 0.05). The percentages of foal fibroblast-derived SCNT embryos developed to 2-cell, 4-8 cell and morula stages were 41.5% (22/53), 33.9% (18/53) and 15.1% (8/53) respectively, while the percentages of adult horse fibroblast-derived SCNT embryos developed to 2-cell and 4-8-cell stages were 38.9% (7/18) and 22.2% (4/18) respectively, but no morula stage embryos were obtained (Fig.5; Table 2). In summary, season and COCs type affect the efficiency of parthenogenetic activation of horse oocyte, and different sources of nuclear donor cells affect the success rate of cloned embryo development.