Abstract
Embryonic freezing plays an important role in assisted reproductive technology in mutton sheep. It allows ewes to undergo multiple plants during the ovarian stimulation cycle. Embryo transfer improves the pregnancy rate of ewes and multiple pregnancy, and the programmed freezing method is widely used in clinical practice after years of clinical trials, and has become a classic embryo freezing method. In 1990, Gordts et al reported pregnancy because of dividing embryos from vitrification frozen mutton sheep. It marks the clinical practice of vitrification preservation technology. In recent years, the glass vitrification freezing technology is more convenient and consumes less than the traditional procedure. During the freezing process, it can avoid the formation of ice crystals inside and outside the cells, and further adopted in the stall laboratory. The findings suggest that vitrification is more likely than procedural freezing, although embryo survival, does not improve implant rate, but findings have been reported. Vitrification affects not only embryo survival rate but also clinical pregnancy rate and implant rate. It is not yet known which method has an absolute advantage. The technology of embryo freezing and resuscitation of mutton sheep has been continuously improved since the 1980s. At present, the methods are mature and the results have been stable for generations. It is a routine technology in the field of assisted mutton sheep reproduction, and it is also the only recognized clinical method of fertility preservation at present. The technology of mutton sheep embryo freezing and resuscitation has effectively solved the retention problem of the remaining mutton sheep embryos. This paper mainly introduces the technical principle, common methods and practical experience of mutton sheep embryo freezing and resuscitation. Explore its important role in fertility protection.
References
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