SELENIUM ACCUMULATION AND DISTRIBUTION DYNAMICS IN THE BODY OF SOME FRESHWATER FISH SPECIES WHEN ADDING SELENIUM-CONTAINING FEED SUPPLEMENTS
The paper presents the studies on the effects of a diacetophenonyl selenide preparation on selenium accumulation and distribution dynamics in the body of some fish species widely inhabiting the basin of the Volga River within the Saratov Region bred in artificial reservoirs and widely used in human diet. Two groups of fish were studied: the diet of the first trial group was supplemented by diacetophenonyl selenide in doses of 0.02, 0.05, 0.1 and 0.2 mg per kg of feed; the second group was the control and received the standard feed. The selenium-containing preparation was sprayed into the feed. Supplementing the feed of commercial fish species (crucian carp, carp, silver carp, and red eye) with different doses of diacetophenonyl selenide (0.02, 0.05, 0.1 and 0.2 mg per kg of feed) leads to a significant increase in selenium concentration in the tissues as compared to the control. Selenium concentration in tissues and its accumulation dynamics depend on the supplement dose. The highest concentrations were found when a dose of 0.2 mg/kg was added, and the lowest - with a dose of 0.02 mg/kg. The most optimum dose to enrich commodity fish with selenium is 0.2 mg per kg of feed, but selenium content in the body of one fish species may vary considerably. High selenium accumulation was found in the tissues of liver, gonads and in scales, and lowest accumulation - in the tissues of intestine and skeletal muscle; while the background indices of this trace element in pond water ranged from 0.079 ± 0.005 to 0.095 ± 0.006 µg mL.