Multielemental analysis of agroindustrial by-products employed in animal feeding by INAA

Instrumental neutron activation analysis (INAA) with gamma-ray spectrometry was applied to determine As, Ca, Cd, Cl, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Mo , Na, Sb, Se and Zn in the Brazilian agroindustrial by-products. These mate rials are widely used in ruminant feeding. The results obtained were compar ed with requirement and maximum tolerable concentrations. The general concl usions from the data obtained were: (1) many by-products presented concentr ations of some essential elements lower than the requirement concentrations , while in some samples the concentrations of Cr, Fe, Mg and Se exceeded by a little the maximum tolerable concentrations, (2) the elements As, Cd, Hg and Sb, generally considered toxic, showed concentrations lower than maxim um tolerable values.