The results of obtaining eggs from brood sturgeon (Acipenser baerii Brandt, 1869) at first maturity grown in industrial conditions

Purpose. To determine and evaluate productive parameters in the process of artificially obtaining ovulated eggs in different seasons from brood Siberian sturgeon Acipenser baerii Brandt, 1869 at first maturity grown in conditions of floating cage systems with a natural water temperature of the forest-steppe of Ukraine. Methodology. The material for the study were 65 individuals of age-8+ to 10+ sturgeon females with a body weight of 6.02‒8.64 kg firstly used in breeding works, which were grown using intensive technology in floating cages installed in a water body with a natural temperature regime of the forest-steppe zone. Experiments on obtaining mature eggs were conducted in non-traditional breeding periods — in winter (February) and at the end of spring (the last decade of May). In the winter, a recirculation aquaculture system was used with the use of special methods of preparing brood fish in the process of obtaining mature eggs. Collection of ovulated eggs was carried out with the preservation of life of brood fish after hormonal stimulation of gonad maturation using a carp pituitary preparation. Determination of productive parameters and study of physicochemical factors of the environment were carried out according to generally accepted methods. Findings. In different seasons of the year at a water temperature of 14–21°C, high efficiency of gonad maturation was registered in both groups of brood fish. The average weight of mature eggs obtained in separate groups of sturgeon females was 1.02–1.15 kg with an average gonadosomatic index of 13.92–15.42%. 94–97% of fish responded to pituitary stimulation in different groups of brood fish. The duration of brood fish maturation after the second (decisive) injection with a total dose of a gonadotropic substance of 3.5–4.0 mg/kg of fish weight varied within 14–25 hours. The survival rate of brood fish after egg collection was close to 94%. Originality. The results of obtaining mature eggs from Siberian sturgeon (Acipenser baerii) females at first maturity using the industrial fish farming technology, which is not common for aquaculture in Ukraine, were determined and analyzed. Practical value. The study results are of interest for the development of modern sturgeon aquaculture technologies in the conditions of industrial-type farms, primarily for the organization of caviar production.