Analysis of literature data and the results of our own research show that even with intensive rearing of animals with the use of balanced feeding and keeping them in accordance with the technology - it is almost impossible to avoid stress. And especially, excessive man-made load on agroecosystems also has a negative impact on animal life.
 Factors that cause a decrease in immune status and the emergence of immune pathology in animals include: industrial technology of animal husbandry, chemicalization in crop and livestock production, man-made pressure, dietary imbalance in nutrients and biologically active substances. This increases the impact on the body of heavy metals, which displace nutrients from body tissues, in particular trace elements and replace them in metabolic processes, which is a potential prerequisite for the development of oxidative stress. The mechanism of development of stress reaction of an organism is closely connected with activity of POL (lipid peroxidation) and depression of antioxidant potential. Under these conditions, the ability of the organism to mobilize protective and adaptive capabilities in response to the action of negative factors becomes especially important. Keeping productive animals in adverse conditions, unbalanced feeding are components of immobilization stress, which reduces their productivity, affects reproductive function, metabolic and functional disorders, reducing nonspecific and specific resistance of the organism (Fedoruk & Kravtsiv, 2003; Velychko, 2008; Velychko, 2011).
 Under conditions of man-caused load on the environment, respectively, and animals – it is promising to develop effective methods for regulating the activity of the enzymatic system of antioxidant protection with the help of biologically active substances, in particular trace elements. The results of research confirm that this has a positive effect on the formation of productive and adaptive properties of animals.
 The system of antioxidant protection is a necessary part of non-specific reactions of the organism, a component of the processes of its adaptation to environmental conditions, a component of normal life, a factor in maintaining homeostasis. Widespread immunodeficiency and elucidation of the main links of their pathogenesis have exacerbated the problem of regulating disorders of the immune system. Therefore, knowledge of the patterns of formation of the immune status of animals, especially in the early postnatal period, is important in the development of methods for the correction of immunodeficiency, antioxidant protection.
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