title: Cryopreservation of immature equine oocytes, comparing a solid surface vitrification process with open pulled straws and the use of a synthetic ice blocker.
abstract: The objective was to evaluate the effect of three cryopreservation methods on the in vitro maturation (IVM) and membrane integrity (MIn) of immature equine oocytes. An open pulled straw (OPS) method, a novel solid surface vitrification (SSV) process, and the addition of a synthetic ice blocker were evaluated. Compared with the control group (N=269), the OPS (N=159) and the SSV (N=202) cryopreservation methods decreased both IVM (50.9 vs. 13.3 and 9.4%, respectively; P<0.001) and MIn (76.6 vs. 31.1 and 33.7%; P<0.001) of immature equine oocytes. However, inclusion of 0.1% ice blocker in the OPS vitrification process increased the rates of both IVM (30.5%; P<0.01) and MIn (45.8%; P<0.05) of the oocytes (N=59). Including 0.1% ice blocker in the SSV process improved the IVM rate (20.9%; P<0.05), whereas MIn remained compromised in this group (N=67). However, increasing the concentration of the ice blocker (to 1.0%) in the cryopreservation methods did not significantly improve rates of IVM. In conclusion, the addition of a synthetic ice blocker (0.1%) to both cryopreservation processes significantly increased rates of both IVM and MIn of immature equine oocytes cryopreserved by OPS.
authors.affiliation: Laboratório de Embriologia Molecular e Transgênese, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Pelotas, RS, Brazil.
authors.forename: P M M
authors.initials: PM
authors.lastname: de Leon
authors.forename: V F
authors.initials: VF
authors.lastname: Campos
authors.forename: C D
authors.initials: CD
authors.lastname: Corcini
authors.forename: E C S
authors.initials: EC
authors.lastname: Santos
authors.forename: G
authors.initials: G
authors.lastname: Rambo
authors.forename: T
authors.initials: T
authors.lastname: Lucia
authors.forename: J C
authors.initials: JC
authors.lastname: Deschamps
authors.forename: T
authors.initials: T
authors.lastname: Collares
mesh_terms: D000818:Animals; D002470:Cell Survival; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D003451:Cryoprotective Agents / Q000494:pharmacology*; D005307:Fertilization in Vitro / Q000662:veterinary; D006736:Horses; D009865:Oocytes / Q000166:cytology* / Q000187:drug effects / Q000648:ultrastructure
chemical_list: D003451:Cryoprotective Agents