摘要：SummaryFreeze-drying techniques allow the preservation of mammalian spermatozoa without using liquid nitrogen. However, the current method requires the use of glass ampoules, which are breakable, expensive, and bulky to store or transport. In this study, we evaluated whether mouse freeze-dried (FD) spermatozoa can be preserved and transported on thin materials. In this study, we demonstrated that FD sperm can be preserved in thin plastic sheets. Its DNA integrity was comparable to that of glass ampoule spermatozoa, and healthy offspring were obtained after preservation at −30°C for more than 3 months. We attached preserved FD sperm to postcards, and transported these to other laboratory inexpensively at room temperatures without any protection. This method will facilitate the preservation of thousands of mouse strains in a single card holder, promote collaboration between laboratories, conservation of genetic resources, and assisted reproductive technology.Graphical abstractDisplay OmittedHighlights•Successful preservation of mouse freeze-dried (FD) spermatozoa by thin plastic sheet•DNA integrity and developmental potential are comparable to the conventional method•Viable mouse FD sperm can be transferred via an air mail without any protection•Tens of thousands of mouse strains can be preserved in a single “sperm-book”Reproductive medicine; Biological sciences; Biotechnology
