Effect of two types and two concentrations of cryoprotectants on ovine oocytes morphology and viability post-vitrification


Background:Oocyte vitrificationisapromisingtechnique.Thechoiceofappropriatetypesandconcentrationsofcryoprotectants is essential for the success of the oocytes vitrification.Objective:This study aimed to investigate the effect of vitrificationonviabilityandmorphologyofoocytesandto compare the effect of several cryoprotectants on the viability and morphology of oocytes during vitrificationandpost-thawing.Methods:The sheep ovaries were collected from the local abattoir. Only normal and viable oocytes were included in this study. By using cryotop, immature oocytes that were viable with normal morphology were vitrifiedwith 15% DMSO and 15% EG supplemented with 0.0 M, 0.25M, or 0.5 M of either sucrose or trehalose as control and treated groups. Oocytes viability and morphology were assessed post-aspiration and post-thawing.Results:From the results of the present study, the percentage of post-thawing normal and viable oocyte reported with the use of 0.5M trehalose and EG in vitrificationsolution(VS)significantly)P<0.05)higherthanthepercentage of post-thawing normal and viable oocyte reported with use of 0.25 M trehalose and EG.Conclusion:Vitrificationissimpletechniqueandeasytoperformbutitneedssomeexperiencetopreventanyoocyte loss during vitrificationandthawingprocessing.Theuseof0.5Mofeithersucroseortrehalosein vitrificationsolutionimprovesthepercentageofpost-thawingviableandnormaloocytes.