Determination of Bovine Urinary Selenium by an Improved Digestion Method

Abstract

For the determination of urinary selenium a newly developed apparatus (taper joint capillary) was applied to centrifuge tubes for completing digestion and decreasing volatilization of mineral acid. The separated precipitate after the reduction of selenium was dissolved by adding a little amount of distilled water. By this method the variation coefficient of the determined values was below 3% (n=10) and the recovery of selenium added to the urine sample was within 100±3%. Urine samples from 5 lactating Holstein cows and 7 Japanese black cows showed selenium concentrations of 16.8 to 66.8ng/ml and 6.2 to 41.4ng/ml, respectively, by the improved method.