Effects of modest early creep feeding on growth, carcass traits, and muscle composition in pasture-raised Wuranke lambs

Early nutritional supplementation may enhance lamb growth in extensive grassland systems, although its effects on carcass traits and muscle composition under low-input pastoral conditions remain unclear. This study examined the effects of modest early creep feeding on growth performance, carcass traits, and Longissimus dorsi composition in pasture-raised Wuranke lambs. Forty healthy, uncastrated male singleton lambs were assigned to either a control group (CG; pasture only) or an experimental group (EG; pasture plus creep feed) and monitored from birth until approximately 160 days of age. Creep feed was provided for 50 days, with a low average intake of 52.9 g/lamb/day. Growth traits were measured in all lambs (n = 20 per group), whereas carcass evaluation and muscle composition analyses were performed in a subset of eight lambs per group. EG lambs were heavier at the end of supplementation and before slaughter than CG lambs. In the carcass subsample, EG lambs also had greater slaughter weight, hot carcass weight, edible meat weight, and edible meat percentage, whereas the dressing percentage did not differ significantly between groups. The composition of Longissimus dorsi muscle was generally similar between groups. After FDR correction, no significant differences in proximate composition, mineral content, fatty acid profile, or amino acid profile were observed. These findings suggest that modest early creep feeding can improve growth and carcass output in this flock of pasture-raised Wuranke lambs, while no major detectable changes in the measured muscle composition occurred. However, because carcass and muscle composition analyses were based on a small subsample, subtle effects cannot be ruled out. Further multi-flock and multi-season studies incorporating direct measurements and economic evaluation are needed before broader practical recommendations can be made.