Carcass And Meat Quality In Lambs Receiving Natural Tannins From Mimosa Tenuiflora Hay

This study evaluated the level of natural tannins from Mimosa tenuiflora hay replacing Brachiaria decumbens cv. Basilisk hay in the diet of lambs on the composition of the carcass tissue, physicochemical properties, fatty acid profile and sensory attributes of lamb meat. A total of 28 uncastrated Santa Ines lambs with initial average body weight (BW) of 28.0 ? 0.5 kg was distributed in a block randomized design with four treatments each [four levels of inclusion of M. tenuiflora hay, providing four different level of tannins at 1.21 (control or without M. tenuiflora hay), 9.3; 17.4 and 25.4 g/kg dry matter (DM) total] and seven replicates. The inclusion of natural tannins from M. tenuiflora hay in the lamb diet resulted in quadratic increases (P <0.05) in DM intake (DMI), slaughter final weight (SBW), average daily gain (ADG), loin cut weight, muscle weight, subcutaneous fat, water holding capacity (WHC), ?n?6:?n?3 and polyunsaturated fatty acid (PUFA) ratio. The inclusion of tannins in the lamb diet promoted a linear increase (P <0.05) on subcutaneous fat, intermuscular fat, total fat, fat yield, muscle:fat ratio of the leg cut, C18:1n?9?trans, and enzyme activity of ?9?desaturase C18:0. The inclusion of natural tannins in the diet promoted a linear reduction (P <0.05) on the FA C17:0, C18:0, ?SFA, MUFA?trans and thrombogenicity index (TI) and a quadratic reduction on C22:6n?3 (P <0.05) of lamb meat. There was no effect of the inclusion of tannins from M. tenuiflora hay in the diet on tissues weights, pH (24 h), moisture, protein, total lipids, crude ash content, shear force, coloration indexes, cooking weight loss, conjugated linoleic acid (CLA) and sensory attributes of lamb meat. However, meat of the lambs receiving 25.4 g/kg DM of tannin presented a greater (P <0.05) average overall acceptance (7.30) according to the hedonic scale ranging from 1 to 9 and to 9 as extremely like. It is recommended inclusion of M. tenuiflora replacing Brachiaria decumbens hay at 250 g/kg of roughage corresponding to 17.4 g/kg DM of tannins inclusion in the diet of Santa Ines sheep because improves the performance, WHC, overall acceptance, and lipid quality from the reductions in ?SFA and IT, which are associated with cardiovascular disease risk.