Some features of fishery use of reservoirs of complex purpose for growing commercial sturgeon fish in cages

The peculiarities of physical and chemical conditions in the complex purpose reservoir (VKN) of the village of Abdi of the Tyulyachinsky district of the Republic of Tatarstan in the area of the cage line for growing commercial sturgeon fish were studied. A study of the physical and chemical characteristics of water in the area of the cages revealed that the average concentration of dissolved oxygen in the surface layer of water in the summer was 9.5±0.2 mg/l, in the autumn period — 8.6±0.1 mg/l. pH values throughout the season were above 7.2. The average electrical conductivity of 547±8 μS/cm during the minimum level mode (in autumn) makes it possible to attribute the water of VKN with. Abdi to water of good quality. The total antioxidant activity of water in winter varied from 0.8112 up to 1.5548 mgRu/L. It was concluded that in the cage cultivation of valuable fish species, it is necessary to control the level of oxygen in the water and pH values, since the saturation of water with oxygen in combination with the alkaline reaction of the medium allows to increase the processing rate of metabolites and organic pollutants. To ensure optimal conditions in the cages, it is necessary to use an aerator. It was shown that according to microbiological characteristics of water quality in the area of the cage line in VKN, water corresponds to the mesosaprobic zone of water quality. Proposed is a cage line of eight cages for placement in a channel-type VKN on a small river. Data were obtained on the actual weight growth rate of hybrids of Russian-Lena sturgeon during commercial cultivation on domestic feed in a pontoon cage line in conditions of temperature and level regimes in the channel-type VKN. The prospects and economic efficiency of industrial methods for growing sturgeon fish in agricultural small reservoirs of complex purpose using cage lines are shown.