Tissue composition and meat quality of lambs fed diets containing whole-plant sesame silage as a replacement for whole-plant corn silage

Abstract

The purpose of this study was to evaluate the effects of the replacement of whole-plant corn silage (WPCS) by whole-plant sesame silage (WPSS) in diets of lambs on leg tissue composition, physicochemical properties, and fatty acids profile of the meat. Forty castrated Santa Inês crossbred lambs presenting an average initial body weight (iBW) of 21.8 ± 1.97 kg were distributed in a randomized block design with four treatments [four replacement levels: (control (no sesame), 333, 670, and 1000 g/kg of DM)] in ten replications. No effect (P > 0.05) of replacing WPCS with WPSS was observed on DM intake, final weight at slaughter, weight gain, leg weight, the proportion of muscle (M), bone (B), fat (F), and other tissues, muscularity, M:B ratio, M:F ratio, protein content, ash, pH, water holding capacity, cooking losses, shear force, color parameters (L*, a*, b*, C* and H*), ƩPUFA, ƩMUFA:ƩSFA ratio, Ʃn-6:Ʃn-3 ratio, h:H, atherogenicity index (AI) and on the activity of enzymes Δ9-desaturase C18 and elongase. WPSS promoted quadratic increase (P < 0.05) in the moisture content and quadratic increase trend in C4:0 (P = 0.08). The inclusion of WPSS caused linear increases (P < 0.05) in the concentrations of C18:1 n-11trans, C18:2 c9trans-11 (CLA), ƩMUFAtrans, and ƩPUFA:ƩSFA ratio, and linear increase trend in C18:2 trans10c12 (P = 0.06) and C18:3 n-3 (P = 0.08). It was observed a linear decrease (P < 0.05) in the contents of C16:0, total FA, ƩSFA, ƩMUFA, ƩMUFAcis, and desirable FA, and a linearly decreasing trend in the thrombogenicity index (TI; P = 0.07). Ʃn-6 presented quadratic reduction (P = 0.03), while Ʃn-3 (P = 0.07) and Δ9-desaturase C16 enzyme activity (P = 0.06) tended toward quadratic reduction. WPSS can fully replace WPCS as it does not compromise performance, tissue composition, and meat physicochemical parameters, and improves the quality of meat fat as it reduces ƩSFA and TI and increases CLA content and PUFA:SFA ratio.