Direct comparison of effects of slow-freezing and vitrification procedures on rabbit late blastocyst transcriptome

Nowadays there is a need to improve cryopreservation protocols in both human assisted reproduction and domestic animal field. We wanted to compare the transcriptomic changes induced by two commonly used cryopreservation procedures (slow freezing and vitrification) on rabbit late blastocyst before the onset of implantation. We recovered rabbit morulae at day 3 of development, freezing or vitrified and transferred them into recipient maternal tracts till day 6 of development. In this way, we wanted to analyse if different cryopreservation techniques produce different effects on gene expression that embryos are unable to get over after three days of in vivo development. After artificially insemination morulae were recovered at day 3 of development, frozen or vitrified, and then transferred to recipient does. To assess gene expression differences between frozen and vitrified the recipients were slaughtered three days after the transfer, at day 6.