The elemental status of carp when biologically active feed additives are introduced into the diet

Carp (Cyprinus carpio) is one of the most popular freshwater fish species grown in aquaculture. However, there are a number of problems associated with the breeding of aquatic organisms, including due to the high cost of feed and the increase in the number of diseases. Among the proposed solutions to the problems is the additional inclusion of feed additives in the diet of aquatic organisms. The article examines the elemental status of carp when biologically active feed additives are used in the diet. Yearlings of carp were used as an object. The main accounting period was 42 days, during which the fish were additionally given vanillin (25 mg/kg of feed), probiotic (1 g/kg of feed), ultrafine particles of silicon dioxide (UFP SiO2) (200 mg/kg of feed), trace elements (Zn (20 mg/kg of feed), I (0.6 mg/kg of feed), Cr (2 mg/kg of feed), Co (2 mg/kg of feed)) and their complexes. The effect of feed preparations on the concentration of chemical elements in carp muscle tissue was revealed. It was noted that the inclusion of vanillin in the diet of carp contributed to an increase in the concentration of macro- and microelements: Ca (P  0.05), Na (P  0.01), Fe (P  0.05), Ni (P  0.05), Mo (P  0.05) relative to the control. Probiotics affected the content of elements such as Ca (P  0.05), Na (P  0.05), Se (P  0.05) and I (P  0.05), with a decrease in Cr (P  0.05). The combined use of vanillin and probiotic resulted in an increase in Na (P  0.01) and a decrease in Cr (P  0.01). The complex consisting of vanillin + ultrafine particles SiO2 + probiotic contributed to an increase in the concentration of K (P  0.05) and Na (P  0.01), with a decrease in B (P  0.05), Se (P  0.05) and Mo (P  0.05). The additional use of vanillin + ultrafine particles SiO2 + trace elements (Zn, I, Cr, Co) in the diet of carp was reflected in an increase in the levels of K (P  0.05) and Na (P  0.01), while B (P  0.01) and Se (P  0.05) decreased compared with the control values. After using biologically active feed additives, the concentration of toxic elements in carp tissues decreased to 94.3 % (P ≤ 0.001) compared with the control values. Thus, the additional use of feed preparations in the fish diet is associated with an improvement in the elemental status, with an overall increase in macro- and microelements and a decrease in toxic ones. A general increase in the content of macro- and microelements was revealed, with a decrease in toxic elements. The greatest positive difference was recorded in the group where the fish were additionally injected with vanillin.