Abstract. The aim of this study was to determine the influence of linseed and sunflower oil supplementation on the survival rate, weight gain and feed conversion ratio in carp (CyprinuscarpioL.), raised inarecirculating system. The fish in the experiment were reared in concrete tanks

V. Atanasov, E. Valkova, G. Kostadinova, G. Petkov, N. Georgieva, Ts. Yablanski, G.Nikolov Abstract. The concentrations of 8 elements (Fe, Mn, Cu, Cr, Ni, Zn, Pb and Cd) were determined in the water and liver by common carp (Cyprinus carpio L.) from 6 waterbodies in Stara Zagora regio