High-Speed Imaging of Intra-Embryonic Phase Transformation Events During Rapid Freezing of Zebrafish Embryos

The zebrafish (Danio rerio) represents an increasingly popular vertebrate animal model valuable for genetic and developmental biology research, due to its rapid rate of reproduction and the ability to directly observe the growing embryos, which are optically clear and develop ex vivo. However, the need to maintain live stock of each genetic strain (the number of which is growing exponentially) is risky and prohibitively costly. Although long-term banking of frozen embryos would solve this problem, to date, no adequate method for cryopreservation of zebrafish embryos has been found (Hagedorn et al., 2004).