Abstract

The possible effects of cadmium on the reproduction of cattle after lifelong exposure were investigated with a historical follow-up. The cattle lived on farms were surveilled by the regional veterinary health services between 1976 and 1986. 10 exposed farms in the Kempen were compared to 40 farms from a reference area. Decreased fertility, congenital malformations, foetal death, complications at birth and a decreased twinning rate were expected. An increased rate of slaughter of the cows was expected as well. 19591 gestations and 3798 cows were compared. Logistic models and Cox proportional hazard models were used. Fewer twins were born, more complications at birth occurred for both calf and cow and more inseminations were needed. No other differences were found. The results are consistent with those of other investigations. The conclusion is that there are differences in the reproduction of cattle between the Kempen and the reference area. These differences are possibly related to reduced implantation of embryos due to cadmium.