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1 <br />' Dietary study <br />Changes in survival or growth of larval razorback sucker in response to selenium <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />exposure were not detected over the concentration range studied (Table 4; Figure 1). Average <br />survival across all exposure treatments was approximately 93%. Of the three endpoints <br />investigated (survival, growth in mass, and growth in TL), only TL data showed a potential effect <br />due to exposure to selenium. Statistical analysis of TL data did not detect a trend in size due to <br />exposure (p = 0.586), but did suggest that fish in the dietary-exposure treatment were smaller <br />compared to fish fed the control diet (p = 0.0621). This p-value is higher than the traditional <br />value for statistical significance ofp = 0.05, but it suggests that a subtle effect may have occurred <br />over the concentration range investigated. <br />The magnitude of selenium bioaccumulation in algae and rotifer was less than expected. <br />Concentrations in rotifer ranged from 0.0349 µg/g for the control to 1.40 µg/g for the 27.2 µg/L <br />exposure culture (Table 3; Figure 2). Research by other investigators using similar algae and <br />rotifer culture conditions showed that concentrations as high as about 14 µg/g could be expected <br />in the highest dissolved selenium exposure culture (Dobbs et al. 1996). <br />Renewal-acute tests <br />Median lethal concentrations and 95% confidence limits (in pazentheses) for razorback <br />sucker and fathead minnow exposed to dissolved selenium were 40.8 (37.0, 44.9) and 33.3 mg/L <br />two species were parallel (p = 0.555; Table 5), but that intercepts of the regression lines were <br />(29.8, 37.1), respectively. Statistical analysis revealed that the concentration responses for the <br />15 <br /> <br />