Survey of bioavailable selenium in Sweden with the moose (Alces alces L.) as monitoring animal

Liver tissues were collected from moose (Alces alces L.) from the regular hunting seasons of 1981 and 1982. The material (from about 4300 animals) was stored at -20 degrees C at the National Veterinary Institute (SVA). From this material, 2080 specimens from 12 counties representing 14 regions were analyzed for selenium. The counties included were Norrbotten, Västernorrland (northern region), Uppsala, Kopparberg, Gävleborg, Jämtland (central region), north and south Kalmar (eastern region), Halland, north and south Alvsborg (western region), and Blekinge, Kristianstad and Malmöhus (southern region). The analysis was performed by a combination of continuous hydride generation using a flow-injection technique and atomic absorption spectrometry. The median selenium concentration in the liver in the entire material was 0.15 and the mean (+/- S.D.) 0.25 +/- 0.29 (range: 0.03-3.1) mg/kg wet wt. The highest median values obtained were 0.26, 0.28 and 0.29 mg/kg, in the counties of Gävleborg (central region) and north and south Alvsborg (western region), respectively. The lowest medians, 0.09-0.10 mg/kg, were found in the counties of Uppsala (central region), north and south Kalmar (eastern region), and Jämtland (central region). Intermediate median values were obtained in the other counties: 0.13 mg/kg in the county of Västernorrland (northern region), 0.15-0.16 mg/kg in the counties of Blekinge and Malmöhus (southern region) and Norrbotten (northern region), 0.18 mg/kg in the county of Halland (western region), and 0.23 mg/kg in the counties of Kristianstad and Kopparberg (southern and central regions, respectively). Selenium concentrations < 0.1 mg/kg in the liver of cattle are considered to be deficient. In some of the regions, 50-60% of the moose livers showed values below this level. The results indicate that the moose is useful for monitoring the amount of selenium available for wild-grazing animals and confirm that the Swedish environment is poor in selenium.