Всероссийский научно-исследовательский институт физиологии, биохимии и питания животных – филиал Федерального государственного бюджетного научного учреждения «Федеральный научный центр животноводства – ВИЖ имени академика Л.К. Эрнста»
ABSTRACT. There was proposed the more refined method of vitrification of mouse and rabbit embryos in open super superfine capillaries. Equilibration of embryos in vitrification medium was performed in two steps: 1) in the course of 2 min in DPBS + 10% FCS + 7.5% ethylene glycol + 7.5% DMSO; 2) in the course of 30-40 sec in DPBS + 10% FCS + 16.5% ethylene glycol + 16.5% DMSO + 0.5 М sucrose; thereafter embryos were placed in plastic capillary and submerged in liquid nitrogen. The embryos were thawed out and washed off in 3 steps: during 2.5 min in DPBS + 10% FCS + 0.5 М sucrose; 2) during 2.5 min in DPBS + 10% FCS + 0.25 Мsucrose; during 1 min in DPBS + 10% FCS. Using this scheme, vitrification of mouse embryos on the stages of 8 blastomers and blastocyst did not exert a negative effect on their viability. Vitrification of one-cell and 4-cell embryos diminished a fraction of embryos developing up to stage of blastocyst to 45 and 15.6% vs 86.7 and 95.2 in the control respectively. Vitrification of rabbit embryos on the stage of blastocist did not exert a negative action on their viability; vitrification of rabbit embryos on the stage 8-16 blastomers diminished a fraction of embryos developing up to stage of blastocyst to 62.5 vs 100% in the control respectively. The proposed method of vitrification makes possible, without decrease in viability, cryopreserve mouse embryos on the stages of 8blastomers and blastocyst, and rabbit embryos – on the stage of blastocyst.
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