AUTHOR=Palazzese Luca , Turri Federica , Anzalone Debora Agata , Saragusty Joseph , Bonnet Jacques , Colotte Marthe , Tuffet Sophie , Pizzi Flavia , Luciani Alessia , Matsukawa Kazutsugu , Czernik Marta , Loi Pasqualino TITLE=Reviving vacuum-dried encapsulated ram spermatozoa via ICSI after 2 years of storage JOURNAL=Frontiers in Veterinary Science VOLUME=10 YEAR=2023 URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2023.1270266 DOI=10.3389/fvets.2023.1270266 ISSN=2297-1769 ABSTRACT=Introduction

Freeze-drying techniques give alternative preservation mammalian spermatozoa without liquid nitrogen. However, most of the work has been conducted in the laboratory mouse, while little information has been gathered on large animals that could also benefit from this kind of storage.

Methods

This work adapted a technique known as vacuum-drying encapsulation (VDE), originally developed for nucleic acid conservation in anhydrous state, to ram spermatozoa, and compared it to canonical lyophilization (FD), testing long-term storage at room temperature (RT) and 4°C.

Results and discussion

The results demonstrated better structural stability, namely lipid composition and DNA integrity, in VDE spermatozoa than FD ones, with outcomes at RT storage comparable to 4°C. Likewise, in VDE the embryonic development was higher than in FD samples (12.8% vs. 8.7%, p < 0.001, respectively). Our findings indicated that in large mammals, it is important to consider dehydration-related changes in sperm polyunsaturated fatty acids coupled with DNA alterations, given their crucial role in embryonic development.