title: Effects of polyethylene glycol and a synthetic ice blocker during vitrification of immature porcine oocytes on survival and subsequent embryo development.
abstract: We evaluated the effects of polyethylene glycol (PEG) and Supercool X-1000 (SC) as supplements during the vitrification of immature cumulus-enclosed porcine oocytes in a solution based on 17.5% ethylene glycol + 17.5% propylene glycol. After warming, the oocytes were subjected to in vitro maturation, fertilization and embryo culture. In Experiment 1, equilibration and vitrification solutions were supplemented with or without 2% (w/v) PEG (PEG+ and PEG-, respectively). The survival rate, cleavage and blastocyst development were similar between PEG+ and PEG- groups; however, all values were lower than those in the non-vitrified control. In Experiment 2, vitrification solution was supplemented with or without 1% (v/v) SC (SC+ and SC-, respectively). The percentages of survival and blastocyst development were similar between SC+ and SC- groups but lower than those in the non-vitrified control. The percentage of cleavage in the SC- group was significantly lower than the control and the SC+ groups, which were in turn similar to one another. In both experiments, the cell numbers in blastocysts were not significantly different among the non-vitrified and vitrified groups. In conclusion, PEG did not improve oocyte survival and embryo development, whereas SC improved the ability of surviving oocytes to cleave but not to develop into blastocysts.
authors.affiliation: Institute of Livestock and Glassland Science, National Agriculture and Food Research Organization (NARO), Ibaraki, Japan.
authors.forename: Elisa Caroline da Silva
authors.initials: ECDS
authors.lastname: Santos
authors.affiliation: Institute of Livestock and Glassland Science, National Agriculture and Food Research Organization (NARO), Ibaraki, Japan.
authors.forename: Tamas
authors.initials: T
authors.lastname: Somfai
authors.affiliation: Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Ibaraki, Japan.
authors.forename: Ruth
authors.initials: R
authors.lastname: Appeltant
authors.affiliation: Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Ibaraki, Japan.
authors.forename: Thanh Quang
authors.initials: TQ
authors.lastname: Dang-Nguyen
authors.affiliation: Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Ibaraki, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Noguchi
authors.affiliation: Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Ibaraki, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kaneko
authors.affiliation: Division of Animal Sciences, Institute of Agrobiological Sciences, National Agriculture and Food Research Organization (NARO), Ibaraki, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kikuchi
mesh_terms: D000818:Animals; D002119:Calcium Carbonate; D002470:Cell Survival; D002951:Citrates; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents; D004338:Drug Combinations; D046149:Embryo Culture Techniques; D047108:Embryonic Development; D005307:Fertilization in Vitro; D007053:Ice; D059471:In Vitro Oocyte Maturation Techniques; D008277:Magnesium Oxide; D009865:Oocytes; D011092:Polyethylene Glycols; D013552:Swine; D058989:Vitrification
chemical_list: D002951:Citrates; D003451:Cryoprotective Agents; D004338:Drug Combinations; D007053:Ice; C050615:Suby's G solution; D008277:Magnesium Oxide; D011092:Polyethylene Glycols; D002119:Calcium Carbonate
keywords: immature oocyte; pig; polyethylene glycol; synthetic ice blocker; vitrification