The effects of the use of complex minerals on the occurrence of retained placenta during pre-partum were valued on 135 Holstein cows from two or more deliveries. The animals were divided in two groups: ionic mineral (69 animals) and complexed mineral (66 animals). In 55 of these animals serum concentrations of imunoglobulin G (IgG), Zn and Cu and colostrum quality were also evaluated. The experiment was conducted in complete randomized split-plot design, serum IgG and trace minerals were evaluated by analysis of variance and used, respectively, Duncan's test and Fisher. The α error rate of 7% was accepted. There were no differences between groups for the occurrence of retained placenta, colostrum quality and serum concentrations of Zn and IgG (P>0.07), a difference was observed for Cu (P<0.07) concentrations. The IgG concentrations were different on the weeks pre partum evaluated (P <0.07).
cupper; immunoglobulin; placenta retention; zinc
