Comparison of micromanipulation mechanical enucleation methods of bovine oocytes

Oocytes of Yanbian Yellow Cattle were enucleated by methods of squeezing enucleation,blind enucleation and point-hitting enucleation,then compared in operating time,achievement rate,enucleation rate and proportion of reconstituted embryos.The results showed that blind enucleation was lower than the other two ways in enucleation rate.Higher success rate were obtained using squeezing enucleation and point-hitting enucleation.The shorter time-consuming methods were squeezing enucleation and blind enucleation;there is no significant difference in cleavage rate and blastocyst rate.Therefore,the methods of squeezing enucleation was a practical enucleation method of Yanbian Yellow Cattle oocytes.