Dietary copper in excess of nutritional requirement reduces plasma and breast muscle cholesterol of chickens

Abstract

Male commercial broiler strain chickens were fed from hatching to 42 d of age either a control diet (based on corn and soybean meal) or the control diet supplemented with 250 mg copper/kg diet from cupric sulfate pentahydrate (for 35 or 42 d). Hypocholesterolemia (11.8% reduction) and decreased breast muscle cholesterol (20.4% reduction) were observed in copper-supplemented birds. There was a slight increase (P > .05) in breast muscle copper (14.5%), and all levels were very low (< .5 mg/kg). Feeding copper for 42 vs 35 d resulted in lower levels of cholesterol in the plasma (12.9 vs 10.8% reduction) and breast muscle (24.6 vs 16.2% reduction). Very similar results were found in two additional experiments in which hypocholesterolemia and reduced breast muscle cholesterol were associated with reduced plasma triglycerides and blood reduced glutathione. It is well known that hypercholesterolemia is a symptom of dietary copper deficiency. The data presented here indicate that blood and breast muscle cholesterol are inversely related to dietary copper in excess of the dietary requirement for maximal growth. The cholesterol content of the edible muscle tissue of broiler chickens can be reduced by approximately 25% after feeding a supranormal level of copper for 42 d without altering the growth of the chickens or substantially increasing the copper content of the edible meat.