Concentrations of Some Elements in Dairy Cows with Reproductive Disorders

Serum Ca, P, Mg, Zn, and Cu concentrations in cows affected with reproductive disorders were determined. A possible relation between serum concentrations of these elements and reproductive diseases was evaluated. In total, 109 Holstein cows ageing between 3 and 9 years were investigated. Thirty-six cows showed postpartum anoestrous, fifty-six were repeat breeders, and seventeen cows served as controls. The mean concentration of Ca in cows with repeat breeding was found to be significantly higher (P<0.01) than that in the control and anoestrous group. The P concentration in cows with repeat breeding and anoestrus was significantly lower (P<0.01) than in the control group. The mean Mg concentrations were almost identical for these three groups. Although the levels of Zn and Cu in cows with repeat breeding and anoestrus were lower than in the control group, the variations were not statistically significant. As the aetiology of the reproductive diseases is very broad, even a slight decrease in serum levels of Zn and Cu may induce or predispose animals to repeat breeding and anoestrus. In the light of these findings, the rations of animals with reproductive disorders are recommended to be supplemented with Zn, Cu, and P.