Abstract
Cryopreservation of embryos is indispensable in the field of assisted reproduction. At present, many countries use the freezing method to breed meat sheep. Methods Save mutton sheep embryos and obtain certain embryo survival rates, implantation rates, and pregnancy rates. Gestation rates and delivery rates have become mature methods of embryo freezing. But its disadvantages are time-consuming, high cost, and inevitable freeze and thaw. Damage to the embryos is caused by the formation of ice crystals during this process. Therefore, it is necessary to discuss it. An alternative method of freezing the embryos. Vitrification preserves embryonic energy. It can overcome the disadvantages of program freezing and is expected to achieve a higher embryo survival rate. Therefore, more and more scholars are paying attention to it, and become one of the hot issues in the field of assisted reproduction at home and abroad. Vitrification technology mainly uses a high concentration of antifreeze, and then places the rings in frozen tubes immersed in liquid nitrogen. This method is the technique of freezing embryos at a cooling rate in a very short time. At present, the cryopreservation technology of mutton sheep embryos has gradually matured, mainly used for the production and research of mutton sheep. Vitrification is a simple and efficient freezing method developed after programmed freezing and does not require a slow sequential cooling process.
References
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