Effects of iron and copper nanopowders (particle size of 20-40 nm) were investigated on rabbits of 1 month age and heifers of 6 months. For introduction of nanometals into the animal's ration, the mixed fodder was treated with the nanometal powder suspension in such a way: 0.08mg ofnanoiron per kg of animal's body weight and 0.04mg/kg for nanocopper. The weight gain of the heifers who received nanoiron and nanocopper after 8 months was 22.4 and 10.7 percent higher than that of the control, respectively. For the rabbits who received nano Fe and Cu after 3 months, the weight gain was 11.7 and 7.3 percent compared to the control, respectively. Under the action of metal nanopowders morphological indices of blood were changed in comparison with the control: after 8 months the quantity of erythrocytes increased by 19.6 percent, hemoglobin by 17.1 percent and leukocytes by 7.6 percent. There was a realignment in leukocytic formula: the quantity of lymphocytes increased by 9 percent compared to the control. Biogenic metals in superdispersive state were able to stimulate immune, enzymatic and humoral systems of the animal's organism, promoting metabolism. Adding Co and Cu metal nanopowders to the bull-calves fodder rations increased content of Ca by 31.8 and 0 percent, Fe by 38.8 and 37.5 percent, K by 19.2 and 15.3 percent, Mg by 17.6 and 23.5 percent, Mn by 9.8 and 45 percent and Na by 20.5 and 8.8 percent, respectively, compared to control. Metal nanopowders improved the quality indices and meat productivity of black-white bull-calves, expressed in intensive growth of muscle, tissue and more nutritious meat. The conducted veterinary-sanitary expertise showed that the supplements based on iron, cobalt and copper nanopowders can be used as safe bioactive supplements in animal husbandry.