NINETY-SIX cross-bred (D × H × Y) barrows were used in a completely randomized block experiment with six treatments. Pigs were fed a corn-soy basal diet, low in zinc (31.6 ppm). Treatment combinations were: (A) Basal with no added trace minerals (TM), (B) Basal+TM from reagent grade sources (RTM) and (C), (D), (E) and (F) received the basal diet+chelated TM (CTM) at 100%, 75%, 50% and 25% the level of the RTM of treatment B, respectively. No significant differences due to treatment were observed for average daily gain, feed intake or gain/feed ratio. RTM maintained higher serum Cu levels than CTM. Serum zinc increased with 100% CTM and decreased drastically when 50% and 25% CTM diets were fed. Hair Cu concentrations decreased with all treatments. An increase in hair Zn concentration was obtained with the 100% and 75% CTM diets. The highest bone Cu concentration was produced with 100% CTM, whereas the highest bone Zn values were obtained with RTM followed by the 100% CTM-fed groups. The greatest bone breaking strength value was obtained with pigs fed 100% CTM followed closely by those fed the unsupplemented basal diet. Bone breaking strength decreased markedly with RTM and with the 75, 50 and 25% CTM treatments. Metatarsal bone length and diameter were not significantly affected by dietary treatments.