EN
The studies were performed on 28 calves aged 2—8 weeks. The calves were divided into 4 equal groups. The calves from group I received 500 mg of zinc in a water solution of ZnCl₂ orally, once a day, for 4 weeks; in group II — the same dose of Zn (ZnCl₂) and 2500 mg Mg in a water solution of MgCl₂ X 6H₂O; in group III — only 2500 mg Mg (MgCl₂ X 6H₂O). Group IV acted as the control one. The following parametres were assayed: Zn, Mg, Fe, Cu and Ca concentrations in the serum, the number of erythrocytes, the haemoglobin concentration and the haematocrit value. The administration of zinc chloride for 4 weeks markedly increased the Zn content in the serum. In contrast, the administration of MgCl₂ X 6H₂O did not result in changes of the Mg level in the serum. The use of zinc and magnesium had no influence on Fe, Cu and Ca concentrations in the serum and on the haematological indices of erythrocytes.