Chemical Composition, Carcass and Sensory Characteristics of Grazing Lambs Meat, Supplemented with Different Protein Sources

Aims: This study was conducted to evaluate the effects of different sources of protein supplementation on carcass characteristics and meat quality of Suffolk lambs in intensive grazing system.
Study Design: Samples of meat for chemical composition, carcass characteristics and meat quality were analyzed using a completely randomized design. An analysis by contrasts was carried out; C1) ryegrass hay (RGH) vs. fishmeal (FSM) and soybean meal (SBM) and C2) FSM vs. SBM treatments.
Methodology: Thirty male Suffolk lambs (37.2±5.4 kg live weight) were used to evaluate the carcass characteristics and meat sensory. Animals were grazed on perennial ryegrass 12h/d and supplemented (30 g/kg0.75 live weight) with RGH, FSM or SBM diets.
Results: Carcass performance was increased (P=.024) in FSM and SBM lambs vs. RGH (52.7 vs. 47.9 %). A tendency (P=.079) was observed for the chop thickness at the 12th rib for SBM or FSM vs. RGH lambs. Organoleptic characteristics did not present differences, except juiciness (P=.002). Meat fat content was the only variable that showed differences between treatments (FSM > SBM and RGH; P=.001).
Conclusion: The use of feed supplementation with diets containing SBM or FSM in grazing lambs, did not affect directly on the carcass conformation and the sensory characteristics of meat. Meat juiciness showed a variation regarding the type of feed supplementation used, without affect on meat tenderness, flavor and aroma. Meat fat content was higher in animals feed with FSM diets.