Aim of the present study was to determine the effect of some factors affecting oocyte vitrification of rabbit does including, three cryodevices [Straws (S), Open pulled straws (OPS) and Sealed Open pulled straws (SOPS)] using three cryoprotectant types [40% ethylin glycol (EG), 40% dimethyl sulfoxide (DMSO) and their combination, 20% EG + 20% DMSO). Total of 36 New Zealand white (NZW) rabbit does with (5 mo old and 3.25±0.25 kg LBW) and were used in this study. Ovaries were collected and oocytes were harvested. The oocyte yield was recorded and the number of oocyte/ovary was counted, and oocyte recovery rate was calculated. Results indicated that total number of follicles averaged 36.0/doe and 18.0/ovary. Yield of oocytes averaged 31.3/doe and 15.5/ovary and oocyte recovery rate was 86.2%. Oocyte recovery rate was for 61.96, 11.65, 6.48, and 6.10% for compact, denuded, partial denuded and expanded oocytes, respectively. The corresponding frequency distribution was 71.89, 13.52, 7.52 and 7.07%, respectively. Relative to total number of vitrified oocytes, total survival rate of oocyte was not affected significantly by cryodevice, being 87.30, 83.09 and 85.77% for S, OPS and SOPS, respectively. Post-thaw survival rate of normal oocytes was the highest (68.33%, P<0.05) and abnormal oocytes was the lowest (17.44%, P<0.05) with SOPS and the opposite was obtained for straws (59.43 and 27.87%, respectively, P<0.05). While, OPS showed moderate values (63.31 and 19.78%, respectively), but did not differ significantly from each of straw and SOPS. Total survival rate of oocyte was not affected significantly by cryoprotectant type, being 85.38, 83.45 and 87.22% for EG, DMSO and their combination, respectively. Post-thaw survival rate of normal oocytes was the highest (72.56%, P<0.05) and abnormal oocytes was the lowest (14.66%, P<0.05) with EG+DMSO and the opposite was obtained for EG alone (56.92 and 28.46%, respectively, P<0.05). While, DMSO showed moderate values (61.97 and 21.48%, respectively).
In conclusion, using sealed open pulled straws and combination of 40% ethylin glycol and 40% dimethyl sulfoxide as cryoprotectant solution as vitrification procedures of rabbit oocytes showed the best results of post-vitrification survival rate.