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Immunological and oxidative alterations have been reported around calving in dairy cattle. In addition, the levels of heavy metals rise in the blood around parturition, which might affect body systems. Therefore, in this Research Communication we evaluate the changes in whole blood lead (Pb), arsenic (As), and cadmium (Cd) around calving, in comparison with the beginning of the dry period, and assess the correlations of these elements with immunological factors and oxidative markers. Samples were collected from 30 clinically healthy dairy cows in the early dry period (−6 w), one week before expected calving (−1 w), and one week postpartum (+1 w). The highest concentrations of Pb, As, and Cd were observed at −1 w and all the three elements decreased after parturition leading to significantly lower As and Cd, compared to −1 w (P < 0.05). The lowest levels of tumor necrosis factor-alpha, immunoglobulin G …