Dietary omega-3 and antioxidants improve long-chain omega-3 and lipid oxidation of broiler meat

Background This study aimed to investigate the possibility of producing broiler meat rich in long-chain n-3 polyunsaturated fatty acids especially eicosapentaenoic acid (EPA, C20:5 n-3) and docosahexaenoic acid (DHA, C22:6 n-3) with preventing lipid oxidation of the produced meat by supplementing the diets with linseed oil or fish oil along with vitamin E (Vit. E) or sweet chestnut tannins (SCT) as antioxidants. A total of 144 1-day-old Cobb broiler chicks were divided into six treatments with three replicates, eight chicks each. The treatments were basal diets containing 2 g linseed oil/100 g (T1), 2 g linseed oil/100 g + 200 mg Vit. E/kg (T2) and 2 g linseed oil/100 g + 2 g SCT/kg (T3), 2 g fish oil/100 g (T4), 2 g fish oil/100 g + 200 mg Vit. E/kg (T5), and 2 g fish oil/100 g + 2 g SCT/kg (T6) for 5 weeks. Fatty acid composition, thiobarbituric acid (TBA), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were determined. Results Dietary 2 g fish oil/100 g elevated ( P ≤ 0.001) long-chain omega-3 polyunsaturated fatty acids in broiler meat mainly EPA and DHA. At the same time, dietary fish oil resulted in a significant decrease ( P ≤ 0.001) in α-linolenic acid in broiler meat (6%). However, total omega-3 fatty acids in meat were higher ( P ≤ 0.001) with dietary fish oil than with dietary linseed oil. The ratio of n-6:n-3 PUFA was decreased ( P ≤ 0.001) in the meat of broilers fed diets containing 2 g fish oil/100 g compared with broilers fed diets containing 2 g linseed oil/100 g. The two sources of antioxidant decreased ( P ≤ 0.05) TBA value and increased ( P ≤ 0.05) the DPPH radical scavenging activity in broiler meat compared to the diet without antioxidant. No significant differences observed between chicks fed 2 g SCT/kg or 200 mg Vit. E/kg on TBA and DPPH radical scavenging activity. Conclusions It is concluded that inclusion of 2 g fish oil/100 g in broiler diets elevated levels of long-chain omega-3 PUFA mainly EPA and DHA, but decreased n-6:n-3 ratio. Moreover, the addition of 2 g SCT/kg diet or 200 mg Vit. E/kg diet as antioxidant sources inhibited lipid oxidation and enhanced antioxidant activity value in broiler meat, and each of them had the same effect.