Lohman Brown chickens with age from the 1stto 35thday received the food with high doses ofselenium (Se1 mg/kg), copper (Cu100 mg/kg), or both elements (Se1 + Cu100). Live weight increaseof all three experimental chicken groups was by 9.3, 12.9 and 8.1%, respectively, in comparisonwith the control. The concentration of selenium in the blood of the Se1 group chickenswas by 45.5, in liver by 63.4 and in kidney by 19.7% higher that in organs of control group chickens.Selenium accumulation in organs of Se1 group chickens was highly correlated with increaseof glutathionperoxidase activity in blood (r = 0.90) and in liver (r = 0.85) and with decrease of glutathioneconcentration in liver. In Cu100 group chickens, copper concentration increased by 11.7in blood, in liver by 23.7, and in kidney by 19.9%. Together with more intensive excretion of glutathionefrom hepatocytes, copper concentration in bile increased by 17.7% compared to that incontrol group chickens. Also wing feathers participated in the regulation of copper homeostaticbalance, as copper concentration in feathers increased by 66.7%. The concentration of malondialdehidein liver of chickens from all groups was similar (43.5-45.2 μmol·g-1wet wt.), indicatingthat overload of selenium and copper did not cause profuse production of oxyradicals in the organism.Increased accumulation of selenium and copper in chickens influenced biochemical regulationof iron, zinc and cadmium deposition in liver, kidney, tibia and feather, changing therelations between Se and Fe, Se and Cd, Cu and Fe, Cu and Zn, and Cu and Cd concentrations.The analysis indicates increased tolerance of chicken to loads of selenium (1 mg/kg) and copper(100 mg/kg) doses
