Rabbit Embryo Vitrification Using Cryogenic Straw: An Ultra-Rapid Cooling Technique to Preserve Rabbit Embryos for Long-term Storage

For embryonic vitrification, immerse the embryos in equilibrating solution for 2 minutes, followed by a 1-minute incubation in vitrification solution. At the end of the incubation, load the embryos into a 125-microliter plastic ministraw, and couple the closed end of the straw with an appropriate 1-milliliter microdispenser. Aspirate base medium up to one-third of the straw length, followed by a small air bubble.

Next, use a stereomicroscope to aspirate the embryos in 40 microliters of vitrification solution, followed by another small air bubble in enough base medium to move first liquid fraction up to the cotton end of the ministraw. Then, close the opened end of the ministraw with a straw plug, plunge the ministraw directly into liquid nitrogen to achieve vitrification, and store the ministraw in a liquid nitrogen dewar.