The effect of feeding system on carcass characteristics, non-carcass components and retail cut percentages of lambs

Abstract

Thirty crossbred West African lambs were assigned randomly to three different feeding systems: T1: grass pasture grazing ( Cenchrus ciliaris) +2 h/day of grazing leucaena; T2: grazing pasture +300 g of feed concentrate and T3: grazing only on grass pasture in order to determine the effect of feed supplementation on carcass characteristics, non-carcass components, retail cut percentages and quality of lambs carcasses. Full live weight and empty live weight were 22 and 30% heavier ( p < 0.05) for T1 and T2 with respect to T3. T2 differed from T1 and T3 in hot carcass weight (2.1 and 3.6 kg more) and cold carcass weight (1.2 and 2.2 kg more), respectively. T2 had a higher dressing percentage ( p < 0.05) than T1 and T3 (40.77 vs. 37.88 and 35.07), respectively. T1 and T2 were 24 and 29% more in ribeye area than T3. The conformation was not very favorable in any of the treatments. The conformation of the leg in T1 and T2 was poor (slightly concave) and for T3 very poor (concave). T1 and T2 lambs had lighter feet (0.22 percentage points) and heavier testicles (0.52 and 0.60 percentage points), with respect to T3, respectively. The livers in T2 weighed 14 and 107 g more than in T1 and T3, respectively. T1 and T3, however, had a higher proportion of full intestines (6.32 and 2.64 percentage points, respectively) than T2. There were no differences between treatments ( p > 0.05) for the chop, leg and shoulder neck percentages but there was a difference ( p < 0.05) in the loin percentage in T1 and T2 with respect to T3 (4.69 and 4.57 vs. 3.93) respectively. T2 showed higher percentages of internal and fat deposits in kidneys than T1 and T3. T1 and T3 had light while T2 had moderate external carcass fat. T1 and T2 had slightly dark red muscle color while the muscle color for T3 was cherry red. It was concluded that the combination of feed concentrates and/or Leucaena leucocephala is an alternative in the production of well-finished lamb carcasses with good external fat, meat of better quality and appearance for the consumer and higher percentages in retail cuts.