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<br />o <br />(':) <br />N <br /> <br />t.:':lII <br /> <br />exposure tanks was started 2 days before introducing the selenium-spiked water. <br /> <br />..... Adult Exposure <br />a <br /> <br />Adults were exposed to one of six combinations of dietary and waterborne selenium for <br /> <br />155 days (last day of spawning trials) and then held for 90 days under control conditions to allow <br /> <br />for selenium depuration. To minimized handling, the adults were tested in the same diluter <br /> <br />system in which they were initially stocked (described above). The experimental treatments <br /> <br />were assigned using a balanced 3 x 2 factorial design with three dietary concentrations and two <br /> <br />waterborne concentrations. Treatment designation for the combined dietary and waterborne <br /> <br />selenium concentrations is summarized in the text-table below: <br /> <br />Waterborne Dietary selenium (~g/g dry weight) <br />selenium (ilgIL) Control 5 [0 <br />Control Treatment 1 Treatment 3 Treatment 5 <br />5 Treatment 2 Treatment 4 Treatment 6 <br /> <br />Each treatment had three replicate exposure tanks, which were the experimental units, and two <br /> <br />females and one male were stocked in each tank (except for one replicate of treatment 2 as <br /> <br />discussed above). Thus, six females (five in treatment 2) and three males (four in treatment 2) <br /> <br />were exposed to each treatment. The exposure tanks (total of 18) were arranged in three rows of <br /> <br />six, with all treatments present in each row. The assigrunent of treatments to the tanks followed <br /> <br />"\" <br /> <br />a randomized block design, with rows serving as the blocks (ASTM 1992). <br /> <br />For the dietary exposure component, fish were fed a commercial semi-moist salmon diet <br /> <br />fortified with seleno-DL-methionine to achieve nominal selenium concentrations of 0, 5, or [0 <br /> <br />~glg (dry weight), The dietary selenium concentrations were based on proposed dietary <br /> <br />threshold concentrations of3, 5, and 10 ~glg (Lemly 1993, I 996a, Lemly and Smith 1987, <br /> <br />8 <br />