Comparison of Cryotop and micro volume air cooling methods for cryopreservation of bovine matured oocytes and blastocysts
Year: 2015
Type: article
Abstract: This study was designed to compare the efficiency of the Cryotop method and that of two methods that employ a micro volume air cooling (MVAC) device by analyzing the survival and development of bovine oocytes and blastocysts vitrified using each method. In experiment I, in vitro-matured (IVM) oocytes were vitrified using an MVAC device without direct contact with liquid nitrogen (LN2; MVAC group) or directly plunged into LN2 (MVAC in LN2 group). A third group of IVM oocytes was vitrified using a Cryotop device (Cryotop group). After warming, vitrified oocytes were fertilized in vitro. There were no significant differences in cleavage and blastocyst formation rates among the three vitrified groups, with the rates ranging from 53.1% to 56.6% and 20.0% to 25.5%, respectively; however, the rates were significantly lower (P < 0.05) than those of the fresh control group (89.3% and 43.3%, respectively) and the solution control group (87.3% and 42.0%, respectively). In experiment II, in vitro-produced (IVP) expanded blastocysts were vitrified using the MVAC, MVAC in LN2 and Cryotop methods, warmed and cultured for survival analysis and then compared with the solution control group. The rate of development of vitrified-warmed expanded blastocysts to the hatched blastocyst stage after 24 h of culture was lower in the MVAC in LN2 group than in the solution control group; however, after 48-72 h of culture, the rates did not significantly differ between the groups. These results indicate that the MVAC method without direct LN2 contact is as effective as the standard Cryotop method for vitrification of bovine IVM oocytes and IVP expanded blastocysts.
DOI: 10.1262/jrd.2014-163
Institutions: National Livestock Breeding Center, Suranaree University of Technology, Chulalongkorn University, National Science and Technology Development Agency, National Center for Genetic Engineering and Biotechnology, National Agriculture and Food Research Organization, Seoul National University, Institute of Livestock and Grassland Science, Rakuno Gakuen University
Language: English
Subfield: Reproductive Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $828
Funders: Higher Education Research Promotion, National Science and Technology Development Agency, Suranaree University of Technology, National Research Council of Thailand, Office of the Higher Education Commission, Japan Society for the Promotion of Science, Thailand Graduate Institute of Science and Technology
OpenAlex ID: W821896841