title: A comparison of different vitrification devices and the effect of blastocoele collapse on the cryosurvival of in vitro produced porcine embryos.
abstract: The aim of this study was to determine the optimum conditions for vitrifying in vitro produced day 7 porcine embryos using different vitrification devices and blastocoele collapse methods. Firstly embryos were collapsed by micro-pipetting, needle puncture and sucrose with and without conducting vitrification. In the next experiment, non-collapsed embryos were vitrified in an open device using either superfine open-pulled straws (SOPS) or the CryoLoop(TM) system, or vitrified in a closed device using either the CryoTip(TM) or Cryo Bio(TM)'s high security vitrification system (HSV). The post-thaw survival of embryos vitrified in the open devices did not differ significantly (SOPS: 37.3%; CryoLoop(TM): 37.3%) nor did the post-thaw survival of embryos vitrified in the closed devices (CryoTip™: 38.5%; HSV: 42.5%). The re-expansion rate of embryos that were collapsed via micro-pipetting (76.0%) did not differ from those that were punctured (75.0%) or collapsed via sucrose (79.6%) when vitrification was not performed. However, embryos collapsed via sucrose solutions (24.5%) and needle puncture (16.0%) prior to vitrification were significantly less likely to survive vitrification than the control (non-collapsed) embryos (53.6%, P < 0.05). The findings show that both open and closed vitrification devices were equally effective for the vitrification of porcine blastocysts. Collapsing blastocysts prior to vitrification did not improve survival, which is inconsistent with the findings of studies in other species. This may be due to the extremely sensitive nature of porcine embryos, and/or the invasiveness of the collapsing procedures.
authors.affiliation: Faculty of Veterinary Science, The University of Sydney, NSW 2570, Australia.
authors.forename: Louise Katherine
authors.initials: LK
authors.lastname: Bartolac
authors.forename: Jenna Louise
authors.initials: JL
authors.lastname: Lowe
authors.forename: George
authors.initials: G
authors.lastname: Koustas
authors.forename: Cecilia
authors.initials: C
authors.lastname: Sjöblom
authors.forename: Christopher Gerald
authors.initials: CG
authors.lastname: Grupen
mesh_terms: D000818:Animals; D001755:Blastocyst; D004622:Embryo, Mammalian / Q000502:physiology*; D011309:Preservation, Biological; D013552:Swine; D058989:Vitrification