EFFICIENCY EVALUATION OF USING DIFFERENT SPAWNING INDUCERS IN THE CONDITIONS OF ARTIFICIAL REPRODUCTION OF STЕRLET (ACIPENSER RUTHENUS L.)

Purpose. To study the efficiency of replacing the preparation of sturgeon hypophyses, which is traditional for sturgeon culture but scarce and expensive, with its carp analogue as well as with preparations, which induce own gonadotrophic function of brood sterlet hypophysis when producing offspring in aquaculture conditions. Methodology. The research was performed in the framework of the NULES research theme for 2013?2015, in the conditions of the Fishery Academic, Research and Production Laboratory of the Aquaculture Department (hatching room and fish culture facility with closed water supply in Nemishaev, Borodianka district, Kyiv region). The control in the experiment on a comparative evaluation of the efficiency of different spawning inducers for artificially reproduced sterlet was Reproginol (powder of acetoned sturgeon hypophysis in 50 mg capsules). The experimental variant 1 included acetoned hypophyses of Prussian carp and common carp (no older than a year and half since their collection). The experimental variant 2 is experimental synthetic fish spawning inducer Vadilen-2 (the developer of the preparation is Kovalenko V. O., assistant professor of the Aquaculture Department of the NULES of Ukraine). Collection and processing of experiment data were performed using conventional aquaculture research methods. Findings. It was found that Vadilen-2 produced inducing effect on the gonadotrophic function of sterlet hypophysis and transition from the 4th to the 5th stage of maturation. The effective doses of Vadilen-2 with water temperature of 13?15°C for sterlet females and males were 0.8?1.0 and 0.5?0.6 mg per 1 kg of brood fish, respectively. We observed that sterlet females, which were kept in basins of the recirculated water facility, showed worse results during incubation period when they missed winter period compared to fish, which were kept in the water with natural temperature in the winter. The possibility of replacing the preparation of sturgeon hypophysis with its carp analogue when artificially reproducing sterlet and the advisability of using tannin as a substance for eliminating egg adhesiveness has been justified. Originality. For the first time in Ukraine, a comparative evaluation of using preparations of different origins as well as the nature of the stimulating effect on induction spawning condition in artificially reproduced sterlet was performed and its efficiency was proven. Practical value. The obtained results are recommended to be implemented at enterprises of sturgeon aquaculture. The materials can also be used when writing academic and methodological manuals for training aquaculture specialists at the National University of Life and Environmental Sciences of Ukraine in the specialties of “Water biological resources and aquaculture” and “Water bioresources” (specialization “Sturgeon culture”).