title: Effects of lipid polarisation on survival of in vivo-derived porcine zygotes vitrified by the superfine open pulled-straw method.
abstract: This study aimed to evaluate the post-warming in vitro viability of intact porcine zygotes vitrified using the superfine open pulled-straw (SOPS) method and to investigate whether cryotolerance is increased by lipid polarisation before vitrification. In vivo-derived zygotes (n=317) were either untreated before SOPS vitrification or subjected to one of the following pre-treatments: (1) centrifugation (20 min, 15000 g) or (2) equilibration in high-osmolality medium (6 min, 400 mOsm kg(-1)) followed by centrifugation. Vitrified-warmed and non-vitrified fresh zygotes were cultured in vitro for 120 h. There were no differences in the blastocyst formation rates between the vitrification groups (from 35.4±5.3% to 48.2±5.6%), but fresh zygotes exhibited higher (P<0.001) blastocyst formation rates (87.5±5.3%) than did vitrified-warmed zygotes. The total blastocyst cell number was similar among all groups (from 34.9±2.8 to 44.1±2.8). In conclusion, SOPS vitrification is a promising method for the cryopreservation of untreated in vivo-derived porcine zygotes. Neither lipid polarisation by centrifugation nor exposure to a high-osmolality medium followed by centrifugation affected the post-warming in vitro viability of zygotes. Our study also demonstrated that the donor is an important factor in determining the success of vitrification for in vivo-derived porcine zygotes.
authors.affiliation: Department of Animal Medicine and Surgery, Faculty of Veterinary Medicine, Regional Campus of International Excellence, University of Murcia, E-30071 Murcia, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Gomis
authors.forename: C
authors.initials: C
authors.lastname: Cuello
authors.forename: J
authors.initials: J
authors.lastname: Sanchez-Osorio
authors.forename: M A
authors.initials: MA
authors.lastname: Gil
authors.forename: I
authors.initials: I
authors.lastname: Parrilla
authors.forename: M A
authors.initials: MA
authors.lastname: Angel
authors.forename: J M
authors.initials: JM
authors.lastname: Vazquez
authors.forename: J
authors.initials: J
authors.lastname: Roca
authors.forename: E A
authors.initials: EA
authors.lastname: Martinez
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001755:Blastocyst / Q000166:cytology* / Q000378:metabolism; D002498:Centrifugation / Q000662:veterinary; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D050356:Lipid Metabolism; D013552:Swine / Q000196:embryology*; D058989:Vitrification; D015053:Zygote / Q000166:cytology* / Q000378:metabolism