Effect of lycopene on the copper-induced oxidation of low-density lipoprotein in broiler chickens

The present study was undertaken to investigate whether dietary lycopene ( LP) could prevent the copper-mediated oxidation of low density lipoprotein (LDL), and affect growth performance, relative organ weights, plasma and meat lipid profiles, and LP contents in plasma and tissues in broiler chickens. A total of 160 day-old male broiler chicks were randomly allotted into 16 pens with rice husk as a bedding material. Each experiment had 4 replicates, 10 chicks per replicate (n = 4 per treatment). A corn-soybean meal base diet was used as a control diet (CONT). To formulate the experimental diets, the base diet was added with LP at the levels of 10 (LP10) or 20 mg/kg (LP20), or 17 g/kg of tomato paste (TP17) which was equivalent to 5 ppm of LP. The experiment lasted 4 weeks. Growth performance and relative organ weights were not affected (p > 0.05) by any of dietary treatments. Dietary LP significantly lowered (p < 0.05) triglyceride and LDL cholesterol at 2 weeks of age, but did not affect them at 4 weeks of age. Total cholesterol in thigh meats was not altered by dietary treatments. LP was not detected in leg meats in all chicks, nor in liver or plasma of the CONT group. LP was found in liver and plasma, being the former greater in the concentration, of the chicks fed diets containing LP10, LP20, or TP17. At 2 and 4 weeks, the copper-mediated oxidation of LDL was delayed (p < 0.05) in either LP-or TP-fed chickens compared with the CONT group. In conclusion, LP lowers triglyceride and LDL cholesterol, is deposited into serum and liver, and prevents the LDL oxidation in broiler chickens, confirming the role of LP in the lipid-lowering and antioxidant properties in broiler chickens.