Effects of different copper sources and levels on plasma superoxide dismutase, lipid peroxidation, and copper status of lambs.

This study was performed to determine the effects of different copper (Cu) sources and levels on plasma superoxide dismutase (SOD), lipid peroxidation, and Cu status of lambs. Fifty Dorper × Mongolia wether lambs (approximately 3 month of age; average BW = 23.8 ± 0.6 kg) were divided into five equal groups each with ten animals according to their weight. Treatments consisted of (1) control (no supplemental Cu), (2) 10 mg Cu/kg DM from Cu-lysine, (3) 20 mg Cu/kg DM from Cu-lysine, (4) 10 mg Cu/kg DM from tribasic copper chloride (Cu(2)(OH)(3)Cl; TBCC), and (5) 20 mg Cu/kg DM from TBCC. The Cu concentration was 6.74 mg/kg DM in the basal diet. Plasma copper concentrations and ceruloplasmin activities were not affected on day 30 by Cu supplementation. Copper supplementation increased plasma and liver copper concentrations and ceruloplasmin activities on day 60. Muscle Cu concentrations were not affected by Cu supplementation. There were no differences in plasma, liver, and muscle Cu concentrations and ceruloplasmin activities between Cu-lysine and TBCC. Liver copper concentrations and plasma ceruloplasmin activities were increased in lambs supplemented with 20 mg Cu/kg DM than in those supplemented with 10 mg Cu/kg DM on day 60. However, copper levels had no effects on Cu concentrations in plasma and muscle. Malondialdehyde (MDA) concentrations were decreased in plasma and liver tissues, but not affected in muscle by Cu supplementation. Plasma SOD activities were increased by Cu supplementation. There were no differences in plasma, liver, and muscle MDA concentrations and plasma SOD activities between Cu sources and levels. These results indicated that Cu supplementation increased plasma SOD activity, lipid oxidative stability, and copper status of lambs, but did not influence lipid oxidative stability in sheep muscle. Cu-lysine and TBCC were of similar availability when offered to finishing sheep.