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The work presents systematic, biology, areal diffusion and measures for prevention of the fish species from the family of sturgeons (Acipenseridae). Problems and possibilities of cultivating some sturgeon species in aquaculture are stressed. Based on the past results of sturgeon cultivation in the aquaculture of the Check Republik one has come to the conclusion that the major problems occur in the initial phase of fry cultivation, after the larvae turn to exogene feeding and later when one-year fry turn form natural to industrial food. At the beginning of the cultivation the losses are higher than 50 per cent. The reduction of losses occurs when the fry acquires an individual mass of 1 g, and when the fry adapts to granulated industrial food the losses are minimal. The duration of fry addiction to natural food depends on the respective sturgeon species and varies from the size of 2 to 3 cm (Siberian sturgeon) to 10 to 12 cm (beluga). In autumn in aquaculture the fish-mass of 250 to 450 g (američki veslonos), 450 to 500 g (beluga) and 530 to 650 g (Siberian sturgeon) can acquired. Up to now the research results have shown that a good adaptability and demanding surroundings conditions as well as a quick growth and application of industrial food provide great possibilities for sturgeon cultivation in different aquaculture structures.

This essay analyzes the literary referencelity, in accordance with concepts such as negativity and socialization. In addition, this analysis gives main methodical outlines of literary dialectical sociology. [ABSTRACT FROM AUTHOR]