牛卵母细胞冷冻保存技术研究进展OA

Bovine oocyte cryopreservation is an important component of livestock assisted reproductive technologies and plays a significant role in the preservation and utilization of valuable maternal genetic resources.With advances in cryobiology and assisted reproductive technologies,bovine oocyte cryopreservation has gradually shifted from conventional slow freezing to vitrification,accompanied by continuous improvements in cryodevices,cryoprotectant systems,and cooling and warming protocols.However,bovine oocytes are characterized by a large cell volume,high cytoplasmic lipid content,and high sensitivity to low temperatures.During cryopreservation and warming,they are susceptible to osmotic stress,cryoprotectant toxicity,and temperature fluctuations,which are often accompanied by oxidative stress,mitochondrial dysfunction,and cytoskeletal abnormalities,ultimately compromising subsequent developmental competence.In recent years,considerable progress has been made in improving pre-cryopreservation oocyte quality,optimizing cryoprotectant composition and equilibration protocols,refining cooling and warming conditions,and alleviating cryoinjury.Accordingly,this review summarizes recent advances in bovine oocyte cryopreservation technologies,analyzes the key factors affecting cryopreservation outcomes,reviews progress in cryopreservation protocol optimization and cellular injury regulation,and discusses future directions in this field,with the aim of providing a reference for further improving the efficiency of bovine oocyte cryopreservation and promoting germplasm conservation and genetic improvement in cattle.