The level of primary and secondary lipid per oxidation products were investigated: diene conjugates and malondialdehyde in conditions of nitrate loading. It was established that at bulls feeding with sodium nitrite at a dose of 0.2 hNO3ˉ/kg of body weight, the level of diene conjugates and malondialdehyde in their was increased during the entire the experiment. On the 30thday of the experiment the level of diene conjugates in blood of bull, which were conducted with nitrate load was 7.44 ± 0.15 mmol/l, and the level of malondialdehyde – 0.305 ± 0.014 mmol/l.Under conditions of nitrate load , young cattle was used a new integrated drug «Metisevit», which consists of sodium selenite, vitamin E and metifen. It was found the stimulating effect of metifen and metisevit on antioxidant system of the body of young cattle. Depressing effect of metifen and metisevit on the processes and lipid per oxidation in the blood of bulls under conditions of chronic nitrate–nitrite toxicity. Metifen and metisevit interact with radicals of fatty acids and delay the development of a chain reaction of oxidative stress, reduce the oxidation of phospholipids and form a biologically inactive compound with products of per oxidation of fats. Obtained results of the research indicate antioxidant drugs «Metisevit» and «Metifen» in the application of their young cattle.The mentioned changes are occurring through the comprehensive action of the drug components «Medisvit», that leads to the normalization of metabolic processes and free radical in the body of bulls. Obtained results of the research indicate the antioxidant action of the drugs «Metisevit» and «Metifen» in the application of their young cattle and the reasonableness of their administration to improve the antioxidant status of the organism according to nitrate loading.

Due to the impact of adverse environmental factors, unsatisfactory conditions of pig population, deterioration of food supply, abuse of antibiotics, lack of preventive measures, leads to the development of diseases among pigs, especially young, which leads to a decrease in resistance, body performance, reproduction and reduction of livestock, as well as large economic losses. The use of bacterial preparations from living microorganisms can significantly reduce or even eliminate the use of antibiotics and hormones in the cultivation of healthy animals, to obtain high-quality and safe high-grade products. The aim of the work is to study the effect of probiotic EM – 1 on the physiological state and productivity of young pigs of large white breed. The experiment was conducted on two groups (6 heads each) of animals-analogues, starting from 60 days of age, for 2 months. Animals of the control group received feed produced in the farm. Piglets of the experimental group in addition to the main diet received 5% of feed fermented with em-1. Evaluation of the physiological state and productivity of young pigs was carried out on 60, 90 and 120 days of experience according to the methods adopted in clinical practice. Hygienic, hematological, biochemical, zootechnical and statistical methods of research were used in the performance of the work. The use of probiotic EM-1 in animals of the experimental group led to an increase in hemoglobine concentration by 7.7%, an increase in the number of red blood cells by 13.7%, the total number of leukocytes by 9.52%, and glucose concentration by 11.4%. The advantage of the viability of these pigs for the content of total protein (P < 0.05), γ–globulins by 18.6%, the activity of aminotransferases (AlАT, AsAT; P < 0.05), the average daily gain increased by 12.3% at the end of the experiment. For feeding piglets feed with probiotic EM-1 increased metabolic processes, resistance and productivity of the body, which indicates a higher level of redox reactions in their body.