Behavioral characteristics in open field testing of mice fed selenium-deficient and selenium-supplemented diets

An open field test (OFT) apparatus was used to evaluate the effect of selenium (Se) diets ranging from deficient (0.0 ppm Se) to marginally toxic (1.0 ppm Se) on the behavior of female Balb/c mice. Selenium status of the mice was confirmed fluorometrically, and glutathione peroxidase (GSHPx) and phospholipid hydroperoxide glutathione peroxidase (PLGSHPx) levels were determined in brain and liver tissues. Both GSHPx and PLGSHPx activities were highest in the mice fed the 0.2 ppm Se diet (adequate) and were lowest in the mice fed the 0.0 ppm Se diet (deficient). Animals fed the marginally toxic diet (1.0 ppm Se) had enzyme values slightly lower than those of the adequate (0.2 ppm Se) group. Mice fed the 1.0 ppm Se diet exhibited greater activity in the OFT and entered significantly (P < 0.02) more squares during the open field test than the other animals. They had a significantly lower (P < 0.05) outside to inside squares performance ratio and significantly increased field activity (P < 0.01). These animals also exhibited significantly less (P < 0.05) sniffing behavior than animals fed the 0.2 ppm Se diet. All OFT values for mice fed the Se deficient diets (0.0 ppm Se) were not significantly different (P > 0.05) from those of mice fed the adequate (0.2 ppm Se) selenium diet. Neurological hypersensitivity of animals fed a clinically non-toxic Se diet thus appears to be experimently quantifiable.