Nanodispersed iron oxides (contained mainly magnetit) obtained by the electroerosion dispersion (EED) technology was used to produce developed by M. Monastyrov feed additive Nano-Fe+^TM. The efficiency of feed premixe Nano-Fe+^TM was studied for growing broiler chickens. The method of increasing the productivity of agricultural animals and birds is to introduce iron nanopowder into the feeding ration by spraying feed with a suspension of iron nanopowder with a particle size of 20-30 nm in doses of 0.08-0.1 mg/kg of live weight per day. At the poultry faсtory, Nano-Fe+^TM (suspension of iron oxides in glycerin) was diluted in water at a rate of 10 ml/10 l. The solution was sprayed on the feed of the birds before feeding at a rate of 10 l/1 ton of feed. The following results were obtained when using Nano-Fe+^TM: the live weight gain of chickens increased by 5÷17%; the growth rate of broilers increased by 10÷20%; the protection of poultry from diseases increased by 10÷20%; the effects of stress from vaccination, regrouping, etc. decreased.