title: Cryotop vitrification of porcine parthenogenetic embryos at the early developmental stages.
abstract: The objective of this study was to evaluate the effects of early developmental stages at which Cryotop vitrification is performed on subsequent survival and in vitro development of porcine parthenogenetic activation embryos. The zygotes that were cultured for 4, 8, and 18 hours post electric activation (h.p.a.) and two- and four-cell embryos were vitrified, warmed, and continuously cultured for the remaining period. The zygotes vitrified at 4, 8, and 18 h.p.a. showed similar percentages of survival, cleavage, and blastocyst formation. No difference in viability was observed after vitrification of two- and four-cell embryos, but the embryos vitrified at the two-cell stage exhibited significantly higher blastocyst formation rate than those vitrified at the four-cell stage. However, vitrifying embryos resulted in significantly decreased survival and development rates, regardless of the developmental stage of the embryos. In addition, the final developmental stage, diameter, apoptotic index, and the number of inner cell mass, trophectoderm, and total cells of blastocysts derived from embryos vitrified at any stage of the early culture were similar to those of fresh blastocysts. In conclusion, our data indicate that the early-stage porcine parthenogenetically activated embryos including the zygote, two cells, and four cells have a high ability to survive cryopreservation; these viable embryos after vitrification can produce respectable development rates and good-quality blastocysts.
authors.affiliation: Yunnan Provincial Engineering Laboratory of Animal Genetic Resource Conservation and Germplasm Enhancement, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, People's Republic of China.
authors.forename: Guo-Quan
authors.initials: GQ
authors.lastname: Wu
authors.affiliation: Yunnan Provincial Engineering Laboratory of Animal Genetic Resource Conservation and Germplasm Enhancement, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, People's Republic of China.
authors.forename: Guo-Bo
authors.initials: GB
authors.lastname: Quan
authors.affiliation: Yunnan Provincial Engineering Laboratory of Animal Genetic Resource Conservation and Germplasm Enhancement, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, People's Republic of China.
authors.forename: Qing-Yong
authors.initials: QY
authors.lastname: Shao
authors.affiliation: Yunnan Provincial Engineering Laboratory of Animal Genetic Resource Conservation and Germplasm Enhancement, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, People's Republic of China.
authors.forename: Chun-Rong
authors.initials: CR
authors.lastname: Lv
authors.affiliation: Yunnan Provincial Engineering Laboratory of Animal Genetic Resource Conservation and Germplasm Enhancement, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, People's Republic of China.
authors.forename: Yan-Ting
authors.initials: YT
authors.lastname: Jiang
authors.affiliation: Yunnan Provincial Engineering Laboratory of Animal Genetic Resource Conservation and Germplasm Enhancement, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, People's Republic of China.
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Zhao
authors.affiliation: Yunnan Provincial Engineering Laboratory of Animal Genetic Resource Conservation and Germplasm Enhancement, Yunnan Animal Science and Veterinary Institute, Kunming, Yunnan, People's Republic of China. Electronic address: qionghuahong@163.com.
authors.forename: Qiong-Hua
authors.initials: QH
authors.lastname: Hong
mesh_terms: D000818:Animals; D017209:Apoptosis; D001755:Blastocyst / Q000502:physiology; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D046149:Embryo Culture Techniques / Q000662:veterinary; D004622:Embryo, Mammalian / Q000502:physiology*; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D006358:Hot Temperature; D020287:In Situ Nick-End Labeling; D010312:Parthenogenesis; D013552:Swine / Q000196:embryology*; D015053:Zygote / Q000502:physiology
keywords: Development; Four-cell embryo; Pig; Two-cell embryo; Vitrification; Zygote