The selenium status of dairy cattle in Estonia.

The selenium concentration in milk was very low irrespective of whether there had been a selenium supplementation or not (4.5 and 5.1 μg/l, respectively). This was partly supposed to be caused by a low degree of supplementation, and partly by the fact that selenite – at least in comparison to organic selenium compounds – has been found to be relatively inefficient for increasing the selenium concentration of milk.