Evaluation of selenium in bison and their environment. Sabin, Stacy^*,1, Schauer, Chris², Caton, Joel³, Sedivec, Kevin⁴, ¹ 106 Hultz Hall, Fargo, ND, U.S.A.² Hettinger Research & Extension Center, Hettinger, ND, U.S.A.³ 185 Hultz Hall, Fargo, ND, U.S.A.⁴ 100F Hultz Hall, Fargo, ND, U.S.A.

ABSTRACT- Recent evidence indicates consumption of selenium (Se) in excess of the Recommended Dietary Allowance may provide substantial cancer-protective benefits for humans. The potential enrichment of Se in the meat of bison raised on high-Se soils of the western Dakotas may provide human health benefits due to an increase in dietary Se. The overall objectives of this study were to evaluate Se amounts in soil, vegetation, and bison blood and hair and determine associations between these factors. The study consisted of five locations including NWND1 and NWND2 near Mandaree, ND; SCND northwest of Fort Yates, ND; NCSD southwest of McLaughlin, SD; and SCSD south of Mission, SD. Soil cores from 0 to 15 cm and 15 to 30 cm were collected in July 2003 from six sites at each location and analyzed for Se content. Water soluble soil Se from the 0 to 15 cm soil core was lower (P<0.05) at NWND1, NCSD, SCSD (7.6, 6.6, 7.5 ppb, respectively) than NWND2 (10.3 ppb). Water soluble soil Se from the 15 to 30 cm soil core was greater (P<0.05) at SCSD (10.6 ppb) than NCSD (5.2 ppb). There were no differences in water soluble soil Se between ecological sites (sandy, loamy, shallow, claypan, thin upland) at either soil depth. Vegetation samples (grass, forbs, and Se indicator species) were collected in July 2003 and September/October 2003 from six sites at each location and analyzed for Se. Blood and hair samples were collected from 12 randomly selected mature female bison at each location. Vegetation, blood, and hair samples are currently being analyzed for Se content and once completed, regions of high Se and correlations between Se levels will be determined.

KEY WORDS: selenium, bison, soil, vegetation