Effects of Different Copper Sources and Levels on Plasma Superoxide Dismutase, Lipid Peroxidation, and Copper Status of Lambs

Abstract

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 3month of age; average BW = 23.8 ± 0.6kg) were divided into five equal groups each with ten animals according to their weight. Treatments consisted of (1) control (no supplemental Cu), (2) 10mg Cu/kg DM from Cu-lysine, (3) 20mg Cu/kg DM from Cu-lysine, (4) 10mg Cu/kg DM from tribasic copper chloride (Cu(2)(OH)(3)Cl; TBCC), and (5) 20mg Cu/kg DM from TBCC. The Cu concentration was 6.74mg/kg DM in the basal diet. Plasma copper concentrations and ceruloplasmin activities were not affected on day30 by Cu supplementation. Copper supplementation increased plasma and liver copper concentrations and ceruloplasmin activities on day60. 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 20mg Cu/kg DM than in those supplemented with 10mg Cu/kg DM on day60. 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.