Evaluation of the effects of glucose concentration in extender and sperm concentration in straw for cryopreservation of Atlantic sturgeon (Acipenser oxyrinchus) semen

Abstract

The Atlantic sturgeon (Acipenser oxyrinchus) faces unique conservation challenges due to its extended maturation period and irregular spawning patterns, which restrict its reproductive capacity. Therefore, in order to overcome these difficulties we have made a first attempt to develop effective cryopreservation procedure for Atlantic sturgeon through evaluation of the effects of the glucose concentration in extender and final sperm concentration in straw on sperm motility parameters. A remarkably high (81 ± 8%) postthaw sperm motility was obtained. The other sperm velocity and trajectory parameters were differentially affected both by concentrations of glucose or sperm and cryopreservation process. Our results undoubtedly show that the post-thaw sperm motility of Atlantic sturgeon is highly influenced by the final glucose and sperm concentration. The recommended cryopreservation procedure includes 0.05 M glucose and 7.5% methanol at 1.0×109 spermatozoa ml−1. We have confirmed that our elaborated protocol can be used for cryopreservation of Atlantic sturgeon semen which can be subsequently used for long-term conservation of this endangered species, offering a valuable tool in efforts to safeguard its genetic diversity and contribute to its survival.