Efeito dos métodos de vitrificação, OPS e SSV, com adição de bloqueador sintético de gelo, sobre a viabilidade de oócitos de camundongos e bovinos

Abstract

Oocyte vitrification is a valuable tool for preservation of genetic material. This study compared the effects of vitrification in OPS and SSV, with addition of SupercoolTM X- 1000 (copolymer), on the viability of mature murine oocytes and immature bovine oocytes. Oocytes were vitrified in OPS and SSV, with addition of 0.1%, 1.0% copolymer and without copolymer, besides a control group with no vitrification. Murine oocytes were evaluated for membrane viability, in the first experiment, and for cleavage rate, in the second experiment. Results were superior with the concentration of 0.1% copolymer, for both methods, in the first experiment. In the second experiment, the SSV method without copolymer presented lower cleavage rate (9.2%) than the control group (26.6%). In the third experiment, bovine oocytes were vitrified and evaluated for maturation and membrane viability, but the results were numerically inferior than those for the control group, for both methods. Those results indicate that both vitrification methods can be used with inclusion of 0.1% of copolymer, for mature murine oocytes, considering membrane viability, but the SSV method without copolymer should not be used due to its low cleavage rate. However, the procedures tested in this study are not recommended for cryopreservation of bovine oocytes.