EFFECT OF "ICE BLOCKERS" IN SOLUTIONS FOR VITRIFICATION OF IN VITRO MATURED OVINE OOCYTES

Polymers have been used as a substitute for serum in vitrification solutions for embryos and oocytes. This study was designed to replace serum with defined commercial macromolecules in vitrification solution for in vitro matured ovine oocytes. Oocytes were cryopreserved in two vitrification solutions (16.5% ethylene glycol + 16.5% dimethyl sulphoxide) supplemented with 1% of Super Cool X-1000 and 1% Super Cool Z-1000 (Ice Blockers) or 20% foetal calf serum (FCS). After warming, oocytes viability and developmental potential after processing for in vitro embryo production were assessed. The number of viable oocytes (87.4% and 85.9%), cleaveage rates (21.4% and 19.6%) and blastocyst development rates (4.8% and 4.5%) were similar for Ice Blockers and FCS, respectively. On the basis of these findings, it may be concluded that combined use of Ice Blockers (SuperCool X-1000 and SuperCool Z-1000) as supplementation in vitrification solution offers similar results to serum for vitrification of in vitro matured ovine oocytes.