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The cows in early lactation take less food than they need to produce milk, which is reflected in the change in the metabolic status of cows and can affect to the health of the cows significantly. There are lower zinc concentration in the blood in early lactation, which is related to increased number of somatic cells in milk and occurrence of inflammatory processes. The primary function of zinc is as an antioxidant. It is the micronutrient which has been established as an essential component of the dairy cow diet for maintaining health. Also, zinc plays an important role in the immune response. The total content of zinc in the body is affected by strong homeostatic regulation. For human consumption the best source of zinc are foods of animal origin. The value of zinc concentration in the milk serum of cows in early lactation was 24.78± 13.4 μmol/l, while in mid lactation it was 27.62± 12.8 μmol/l. The results of our study s hows that z inc concentration in the milk serum of cows at different periods of lactation, in first and in sixth month of lactation is approximate and stable during lactation.