Effects of taxol on in-vitro matured bovine oocyte vitrification

Abstract

The experiment was designed to assess the effectiveness of Taxol on cryopreserving bovine MII oocytes using straws as the carrier system for vitrification. Bovine matured oocytes were vitrified in droplets of cryoprotectants with or without 1 µM Taxol (droplet 1: TCM-199, 10% FBS, 5% FCS, 10% ethylene glycol (EG), 10% dimethyl sulfoxide (DMSO) for 45s; droplet 2: TCM-199, 10% FBS, 5% FCS, 20% ethylene glycol (EG), 20% dimethyl sulfoxide (DMSO), 0.5 M sucrose for 25s) on straws. After thawing, the oocytes were cultured in IVM medium in 2 hours and oocytes were assessed by ratio of survival oocytes (SO) to vitrified oocytes (VO); survival oocytes (SO) to colected oocytes (CO) and the proportion of normal nuclear oocytes (NNO). The results showed that the ratio of SO to VO and SO to CO in Taxol groups were slightly higher (62.74 ± 2.74% vs. 59.81 ± 1.75% and 70.65 ± 2.44% vs. 67.66 ± 2.12%, P < 0.05); the ratio of NNO in both taxol-pretreatment groups and non-taxol-pretreatment groups (control) had no significant difference (78.14 ± 4.01% vs. 77.89 ± 2.13%, P > 0.05). The results of this experiment indicated that taxol pretreatment affects the survival ratio of vitrified bovine oocytes but there was no significant evidence on preventing abnormal nuclear oocytes