Determination of selenium and zinc in hair and serum of companion animals by PIXE method

We examined the concentration of selenium and zinc in hairs, sera and feeds using a Particle Induced X-ray Emission (PIXE) analysis. In the pre-treatment of animal hair, it was shown that the radio-frequency heating (FR) ashing method using the Teflon container for tightly sealing and nitric acid is advantageous compared to the conventional wet ashing methods with Kjeldahl flask. The Se concentrations of the sera and hairs in cats were found to be higher than those in dogs (Mann-Whitney's U-test; p<0.01, p<0.05). In the case of dogs and cats fed the diets that have almost the same content of Se, the sera in cats were higher (p<0.05) in Se concentration than in dogs. Therefore, we supposed that the high Se levels of tissues may be characteristics of cats. A significant correlation (r=0.71, p<0.01) between Se concentrations of canine sera and hairs was found. In cats, moreover, a significant correlation (r=0.82, p<0.05) was observed between Ze concentrations of sera and hairs. It was shown that evaluation of selenium and zinc content in serum is possible by measurement of those in animal hair. (author)