Effect of Trehalose on Preservation of Mouse Freeze-Dried Spermatozoa at Room Temperature

Freeze-drying has been frequently used to preserve food at room temperature for extended periods of time; however, its application to mammalian spermatozoa is difficult because it is impossible to preserve spermatozoa at room temperature for long periods. It is known that trehalose is one of the best cryoprotectant agents, but not yet clear whether trehalose is effective for the protection of freeze-dried spermatozoa. In this study, we examined DNA damage of mouse freeze-dried spermatozoa preserved for one week at room temperature with or without trehalose. When freeze-dried spermatozoa were preserved for one week, the DNA damage of spermatozoa and in vitro developmental potential after fertilization had no difference between any concentrations of trehalose. However, when those embryos were transferred into recipient females, the highest birth rate was obtained from embryos fertilized with trehalose treated spermatozoa. These results suggest that the trehalose can protect freeze-dried spermatozoa and increased the quality of embryo for full term development.