The concentration of selenium in bovine milk is related to
selenium concentration in the feed, and there are great
variations worldwide. In South Dakota the selenium concentration
in milk is reported to be between 160 and 1300 ug/l, whereas the concentrations in milk from low-selenium
regions may be from 5 to 30 ug/l [176], as in Scandinavia
and northern Europe. A Swedish study showed that the average selenium concentration in milk was 14 ug/l and the concentration was more than doubled after
supplementation with 3 mg selenium daily from selenium-enriched yeast.