РУАЭСТ (RUAEST)
ALTERNATIVE METHODS OF PREPARATION OF FISH SPERM TO FREEZE AT ULTRA-HIGH VALUES OF COOLING RATE
The sexual products of the Russian sturgeon (Acipenser gьldenstдdtii Brandt, 1833), the Siberian sturgeon of Lena population (Acipenser baerii Brandt, 1869) and white salmons (Stenodus leucichthys Gьldenstдdt, 1772) were used as an object of this research. The aim of the represented research was to study the possibility of freezing of fish men reproductive cells in the form of "thin films" on meshes at ultra-high cooling rates, and also by preliminary drying of a sperm smear in the thermostat. When freezing sturgeon semen in the form of a "thin film", the analysis of motility of post-thawed spermatozoa showed the efficiency of application of this method of preparation of sperm to cryopreservation. The lifespan in all test samples was more than 14 minutes, indicating the suitability of frozen-thawed reproductive cells for aquaculture purposes. The highest spermatozoa lifespan of both Russian and Siberian sturgeons is detected when freezing on plastic samples. In preparation for cryopreservation by preliminary drying of a sperm smear in the thermostat, there was a fluctuation motion of 20 % of sperm. This method of preparation of cells for cryopreservation requires modification and improvement, but the fact that there has been received a certain number of viable spermatozoa, suggests the possibility of application of the given method.