One-step warming does not affect the in vitro viability and cryosurvival of cryotop-vitrified donkey embryos

• Published in: Theriogenology 2020-08, Vol.152, p.47-52
• Main Authors: Bottrel, M., Hidalgo, M., Mogas, T., Pereira, B., Ortiz, I., Díaz-Jiménez, M., Consuegra, C., Morató, R., Dorado, J.
• Format: Article
• Language: English
• Subjects: Animals; Cryopreservation - veterinary; Cryotop vitrification; Culture Media - chemistry; Donkey embryo; Embryo Culture Techniques - veterinary; Embryo, Mammalian - physiology; Equidae - embryology; Heating; One-step warming; Stepwise warming; Sucrose - chemistry; Sucrose dilution; Vitrification
• ISSN: 0093-691X; 1879-3231
• DOI: 10.1016/j.theriogenology.2020.04.026

The objective of this study was to compare the effects of two warming protocols (three-step vs. one-step dilution) on embryo quality, post-warming embryo survival and embryo cell viability of donkey embryos vitrified by the Cryotop method. Twenty, Day 7–8, grade 1–2 donkey embryos were measured, morphologically evaluated and vitrified using the Cryotop technique. Embryos were then randomly warmed using two different warming procedures: (i) W3 (three-step dilution; n = 11): embryos were warmed in 1 M, 0.5 M and 0 M sucrose, and (ii) W1/0.5 (one-step dilution; n = 9): embryos were warmed directly in 0.5 M sucrose. After 3 and 24 h of warming, the embryos were measured and evaluated for their morphology, developmental stage and viability (Propidium Iodide-Hoechst 33,342 dyes). Although both treatments decreased embryo quality after warming (P  0.05) were observed between protocols in terms of post-warming embryo quality, diameter and embryo survival. Greater percentages of dead cells (P