EN
Iron, copper and cobalt belong to the group of elements necessary for living organisms, A metabolic relationship between these elements has been found (1, 2, 6, 11, M, 15, 16), Using the radiologic methods it has been proved that copper is necessary for assimilation, binding and storing of iron in the organism. Vitamin B₁₂ constituting a functional form of cobalt in the metabolism, causes quick transition of iron stored into hemoglobin or erythrocytes, thus accelerating their ripening, The presence of iron in the alimentary tract exerts in its turn a distinct effect on the vitamin B₁₂ resorption from the alimentary tract, increases the production of inner factor necessary for binding, transport and storage of this vitamin. The aim of the present work was to carry out observations on behaviour of iron, copper and vitamin B₁₂ level as a functional form of cobalt in the serum of healthy sheep in different physiological states.