Abstract：
Cryopreservation of oocytes is an important technology for the in vitro gene banking of female germplasm. Although slow freezing is not feasible, porcine oocytes survive vitrification at high rates. Cryopreservation at the germinal vesicle stage appears to be more advantageous than that at the metaphase-II stage. Several factors are considered to affect the success of vitrification and subsequent utilization of immature porcine oocytes such as the device, the protocols for cryoprotectant application, warming, and the post-warming culture. Although live piglets could be obtained from vitrified immature oocytes, their competence to develop to the blastocyst stage is still reduced compared to their non-vitrified counterparts, indicating that there is room for further improvement. Vitrified oocytes suffer various types of damage and alteration which may reduce their developmental ability. Some of these can recover to some extent during subsequent culture, such as the damage of the cytoskeleton and mitochondria. Others such as premature nuclear progression, DNA damage and epigenetic alterations will require further research to be clarified and addressed. To date, the practical application of oocyte vitrification in pigs has been confined to the gene banking of a few native breeds.
摘要：
卵母细胞冷冻保存是雌性种质体外基因库的重要技术。虽然缓慢冷冻是不可行的，猪卵母细胞在高玻璃化条件下存活。生发囊泡阶段的冷冻保存似乎比中期II阶段的冷冻保存更有利。几个因素被认为影响玻璃化的成功和未成熟的猪卵母细胞的后续利用，如装置，冷冻保护剂的应用方案，变暖,和变暖后的文化。虽然活的仔猪可以从玻璃化的未成熟卵母细胞中获得，与非玻璃化的对应物相比，它们发育到胚泡阶段的能力仍然降低，这表明还有进一步改进的空间。玻璃化卵母细胞遭受各种类型的损伤和改变,这可能降低其发育能力。其中一些可以在随后的培养过程中恢复到一定程度，如细胞骨架和线粒体的损伤。其他如过早的核进展，DNA损伤和表观遗传改变将需要进一步的研究来澄清和解决。迄今为止,卵母细胞玻璃化在猪中的实际应用仅限于一些本地品种的基因库。
