Aim. To estimate the impact of additions of different doses of copper, cobalt and iodine salts to the diet of dry and lactating cows on the absorption and removal of 137 Сs from the organism. Methods. Four groups of black and white breed cows –– were selected for the study on the farm in Narodychi district of Zhytomyr region following the traditional methods. The animals were fed salts of microelements with concentrated feedstuffs. Specifi c radioactivity of feedstuffs, feces, urine, milk was defi ned by the gamma-spectrometry method using AMA-OZF analyzer. Results. During the dry period the content of 137 Сs in nutrition of cows of experimental groups was almost the same, whereas its removal from the organism of animals was different depending on the impact of microelements on the degree of radionuclide absorption. The exceeding of the norms of copper and cobalt by 30 % and iodine – by 70 % promotes the decrease of “visible” absorption of cesium and enhances its removal due to the radionuclide, accumulated in the tissues. The radioactivity of the diet of animals dur- ing lactation increased considerably (22–26-fold) and amounted to 17–22 kBq per day; at the same time high bioavailability of the radionuclide was revealed. The increase in 137 Cs content in the diet of cows during the grazing period is related to the use of contaminated fi elds. In May specifi c radioactivity of cow milk was the lowest; its insignifi cant increase (50–65 Bq/l) was observed in June, July and August. The radioactivity of cow milk in September and October increased considerably (150–184 Bq/l). The fortifi cation of the diet of animals of the 3 rd experimental group with copper, cobalt, and iodine promoted the decrease in the radioactivity of cow milk comparing the cow milk of the 1 st experimental group and the milk of the 4 th experimental group. During the lactation period the least absorption of the radionuclide was revealed for the normative consumption of all the microelements, and the highest – for the increased consumption of cobalt only. Conclusions. The vegeta- tive feedstuffs of dairy cattle in Polissia provides the requirement of cobalt for 30–35 %, iodine – for 25–30 %, copper – for 70 % in winter, and during the grazing period in summer – for 25, 35, and 60 % respectively. The fortifi cation of the diet of cows with microelements promotes the decrease in the absorption of 137 Сs in the gastrointestinal tract and its reduced transfer into cow milk.

Leguminous crops grown in the radioactive contamination zone have the potential to accumulate radionuclides 137Cs and 90Sr to a large extent, thus contributing to radioactive contamination of livestock products, milk and meat. One of the effective methods in reducing the accumulation of radionuclides in crop production, in particular fodder, is the application of trace elements that are lacking in the Polissya area of Zhytomyr region. In addition, the trace elements contribute to increasing the yield of plants and improve their nutrition. As a result of the research in the Naroditsky district of Zhytomyr region, Polissya STOV, we found that the application of trace elements in the form of salts of trace elements Co, Cu, Zn, Mn contributed to the increase in the yield of green mass of white lupine and lupine of yellow on 2,4 and 3,6%, or on 10 and 10.7 g, of complexones of these trace elements, respectively, on 11,2 and 13,5%, or on 31,0 and 58,0 ts. Salts of trace elements contributed to a decrease in the specific activity of the green mass of lupine white by 18%, or 1.2 times, yellow lupine - by 11%, 1.2 times. Plasma complexes contributed to a decrease in the specific activity of green mass of white lupine and lupine of yellow on 24%, or in 1,3 times. Specific activity of the green mass of white lupine was high and exceeded the activity of the green mass of lupine yellow in 6.3 times, although the cultivation of cultures was carried out on the same fields, however, at different periods. White lupine was sown in the early spring, during which a considerable amount of precipitation fell during the vegetation period. Therefore, in our opinion, a significant increase in the specific activity of the green mass of white lupine was conditioned by the weather conditions. The maximum specific activity of the green mass of white lupine was 2003 Bq / kg, the minimum is 1526 Bq / kg, which is lower by 477 Bq. Reducing the specific activity of lupine is due to radio-blocking effect of micronutrient complexonates. Salts of trace elements contributed to a 1.2-fold decrease in the specific activity of the green mass of the culture.