A biological assay for determination of availability of selenium for restoring blood plasma gluthathione peroxidase activity in selenium-depleted chicks.
This study was undertaken to develop an assay for the determination of biological availability of selenium. In a preliminary experiment, commercial male, White Leghorn chicks had significantly reduced glutathione peroxidase activity in blood plasma after 7 days of depletion on a selenium-deficient (0.04 ppm of Se) diet. Selenium-depleted chicks fed graded levels of selenium (0.02--0.10 ppm in steps of 0.02 ppm) for 9 days had glutathione peroxidase activity in blood plasma which was linearly, highly correlated with dietary selenium content. In three subsequent experiments, chicks were fed a selenium-deficient diet for 7 days and were then distributed into groups of five chicks each. The standard diets, which contained 0.02, 0.04, 0.06, 0.08 and 0.10 ppm of selenium added as NaHSeO3, and the test diets, which contained three levels of each test substance and provided selenium supplements within the standard range, were each fed to three groups of chicks for 9 days. The dose parameter was selenium, in the standard groups added as NaHSeO3 and in the test groups provided by the selenium present in the test substance. The response parameter was blood plasma glutathione peroxidase activity. Statistical analyses of the results utilizing four fish meals as test substances revealed that the assay complied with the requirements for statistical and fundamental validity.
D000818:Animals; D001681:Biological Assay; D001682:Biological Availability; D002645:Chickens / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D005394:Fish Flour / Q000032:analysis*; D005396:Fish Products / Q000032:analysis*; D005979:Glutathione Peroxidase / Q000097:blood*; D008297:Male; D010544:Peroxidases / Q000097:blood*; D020887:Selenious Acid; D012643:Selenium / Q000008:administration & dosage / Q000032:analysis
D010544:Peroxidases; D005979:Glutathione Peroxidase; D020887:Selenious Acid; D012643:Selenium