In vitroDevelopment of PorcineIn VitroMatured Oocytes Vitrified After Removal of Cytoplasmic Lipid Droplets

The objective of the present study was to investigate the in vitro developmental competence of porcine in vitro matured (IVM) oocytes vitrified after removal of cytoplasmic lipid droplets (delipation). After vitrification and warming, the delipated porcine IVM oocytes were inseminated and subsequently cultured in vitro. The rate of development to the blastocyst stage of delipated, vitrified oocytes (5.9%) was significantly lower than that of control oocytes (untreated oocytes) (26.2%). We also examined the influence of delipation of porcine IVM oocytes on development to the blastocyst stage following in vitro fertilization (IVF). Delipated porcine IVM oocytes (not vitrified) were inseminated and subsequently cultured in vitro. The rates of development to the blastocyst stage were similar for delipated and undelipated oocytes (21.1% and 26.2%, respectively). The results of the present study showed that delipated, vitrified porcine IVM oocytes can develop to the blastocyst stage following IVF, though blastocyst formation rate was low, and that delipation of porcine IVM oocytes did not negatively affect their development to blastocyst stage.