Tolerance of low and high dietary selenium throughout the life span of Syrian hamsters.

In lifetime studies on the effects of dietary selenium (Se) levels, Syrian hamsters were fed diets containing low (unsupplemented torula yeast), adequate (0.1 ppm Se supplemented from sodium selenite), or excessive (5 ppm Se supplemented from sodium selenite) levels of Se. A commercial ration was fed to separate groups. Male and female hamsters were assigned to each diet, and blood samples were collected at 54 and 79 weeks of age for determination of Se status. Body weights of male hamsters were generally highest in those fed unsupplemented diets and lowest in those fed 5 ppm Se supplements. Female weights did not differ between the three semipurified diets. Erythrocyte and plasma glutathione peroxidase and blood Se values increased with the increments in dietary Se at the 54- and 79-week measurements. Survival was approximately 40-45% lower in hamsters fed the commercial ration than in those fed semipurified diets, but was not altered by the Se level in the semipurified diet.