Effects of copper and selenium supplementation on performance and lipid metabolism in confined brangus bulls

Abstract

Twenty-eight Brangus cattle were used to determine the effect of copper and selenium supplementation on performance, feed efficiency, composition of fatty acids in Longissimus dorsi (LD) muscle, and cholesterol concentration in serum and in LD muscle and enzymes activities, reduced glutathione (GSH) and oxidized glutathione (GSSG). The treatments were: i) Control, without copper (Cu) and selenium (Se) supplementation; ii) Se, 2 mg Se/kg of dry matter such as sodium selenite; iii) Cu, 40 mg Cu/kg of dry matter such as copper sulfate; iv) Se/Cu, 2 mg Se/kg of dry matter such as sodium selenite and 40 mg Cu/kg of dry matter such as copper sulfate. LD muscle fatty acid composition was not influenced by the treatments (p>0.05). The serum concentration of cholesterol was not influenced by the treatments (p>0.05), however, the concentration of cholesterol in LD was lower in cattle supplemented with copper and selenium (p<0.05). Oxidized glutathione and reduced glutathione increased (p<0.05) with Cu, Se and Se/Cu supplementation. The supplementation of copper (40 mg/kg DM) and selenium (2 mg/kg DM) altered the metabolism of lipids in confined Brangus cattle, through a decrease in cholesterol deposition in the LD, possibly by changing the ratio between reduced glutathione/oxidized glutathione. Copper and selenium supplementation improved animal performance and feed efficiency (p<0.05) when compared to the control group, providing advantages in the production system, while also benefiting consumers by reducing cholesterol concentration in the meat.

Keywords: Cattle; Cholesterol; Fatty Acids; Minerals; Nutrition.

Figure 1

Concentration of cholesterol and standard deviations in mg per 100 grams of meat, in the Longissimus dorsi muscle of cattle receiving control diet (without supplementation of selenium and copper), copper (40 mg/kg of DM), selenium (2 mg/kg of DM), or selenium (2 mg/kg of DM)/copper (40 mg/kg of DM).

Figure 2

GSH and standard deviations, in μmol per gram of liver, of cattle receiving control diet (without supplementation of selenium and copper), copper (40 mg/kg of DM), selenium (2 mg/kg of DM), or selenium (2 mg/kg of DM)/copper (40 mg/kg of DM).

Figure 3

GSSG and standard deviations, in μmol per gram of liver, of cattle receiving control diet (without supplementation of selenium and copper), copper (40 mg/kg of DM), selenium (2 mg/kg of DM), or selenium (2 mg/kg of DM)/copper (40 mg/kg of DM).

Figure 4

Relation between GSH and GSSG and standard deviations, in μmol per gram of liver, of cattle receiving control diet (without supplementation of selenium and copper), copper (40 mg/kg of DM), selenium (2 mg/kg of DM), or selenium (2 mg/kg of DM)/copper (40 mg/kg of DM).