Acacia mearnsii tannin extract and α-tocopherol supplementation in lamb diet: Effects on growth performance, serum lipid peroxidation and meat quality

Abstract

This study investigated the effects of supplementing lamb diets with plant bioactive compounds α-tocopherol, tannin and the association of both on lamb growth, blood and meat characteristics. Forty male lambs were housed in individual pens and assigned to four treatment groups (10 animals/group), where, for 62 d, they were fed: 1) a basal diet with soybean hulls, soybean meal and corn (Control); 2) the Control diet containing α-tocopherol (Tocopherol); 3) the Control diet containing Acacia mearnsii tannin extract (Tannin); and 4) The Control diet containing A. mearnsii extract and α-tocopherol (Tannin + tocopherol). The Tannin and Tannin + tocopherol treatments resulted in lower cold carcass weight. The concentration of α-tocopherol in the muscle was higher in Tocopherol and Tannin + tocopherol treatments. Meat lipid oxidation, after 7 days of storage, was lower (P ≤ 0.05) in lambs fed Tocopherol and Tannin + tocopherol than in the Tannin treatment, while the treatments with Tannin experienced a trend of reduced serum lipid peroxidation. Tannin diets modified the meat fatty acid profile, with an increase in C17:0 and in the PUFA/MUFA ratio and a decrease in the enzymatic Δ9-desaturase activity (C16 and C18) and in the MUFA/SFA ratio, in addition to promoting a increasing in the sum of PUFAs. Lamb supplementation with α-tocopherol and A. mearnsii tannin are alternatives capable of improving meat quality and reducing serum lipid peroxidation.