Poster from the ISFP congress in Vienna November 2017
Institute of Laboratory Animal Science, University of Veterinary Medicine, Vienna

Cryopreservation of gametes and embryos is a routine method for the long-term preservation of genetic material. The cryopreservation of ovarian tissue offers a valuable addition to these current approaches. The freezing of ovaries with subsequent thawing and surgical engraftment can restore fertility in young women undergoing cancer treatment with chemo- and/or radiotherapy and preserve important lines, strains or races of experimental, domestic and wild animals. During the last decade, several different protocols for the cryopreservation of mouse ovaries were published. In this study we compared four different protocols, which were mostly based on older protocols with some modifications (Liu et al., 2008; Migishima et al., 2003; Wang et al., 2009).

Summary
Ovarian cryopreservation is an easy but invaluable additional tool to archive mouse strains. In summary, all tested protocols used in this study resulted in good pregnancy rates, which did not significantly differ from the pregnancy rate of recipients transplanted with fresh ovaries. Ovarian tissue survived the aforementioned preservation techniques well and resumed follicle development and ovarian cycle after transplantation. Controlled freezing in straws with DMSO as cryoprotectant (protocol Gr. III) resulted in the best performance based on the fast resumption of reproduction and a generally high litter size.