[Indirect and direct determination of selenium levels in the blood of cows with left side displacement of the abomasum].

The selenium level in the blood of cows with left-side displacement of the abomasum (group A, n = 13), healthy herdmates (group B, n = 13), and healthy cows of a neighboring herd free of abomasal displacement (group C, n = 13) was determined indirectly (glutathione peroxidase activity of the erythrocytes) and directly (atomic absorbtion spectroscopy). The cows of groups A, B, and C were similar in terms of the directly and indirectly determined selenium levels of the blood. It is therefore assumed that the selenium level of the blood does not play a causative role in the occurrence of abomasal displacement in cows. By indirect determination higher selenium levels were measured than by the direct method. Possible reasons for this are discussed.