The effects of plastic slatted floor or straw bedding on performance, liver weight and liver copper concentrations in intensively reared lambs

Abstract One hundred and eight Texel sired lambs were weaned at 37 days old and allocated three days later to one of two treatments, using two pens per treatment, in order to evaluate lamb hepatic copper (Cu) values. In Treatment 1 (T1) the lambs were confined to pens having recycled plastic slatted flooring, while in Treatment 2 (T2) the lambs were confined to pens having straw bedded floors, with fresh straw added on alternate days. The lambs had ad libitum access to a coarse lamb concentrate. The crude protein (g/kg DM), crude fibre (g/kg DM), total zinc (mg/kg) and background levels of copper (Cu) (mg/kg) and molybdenum (Mo) (mg/kg) of the diet were 17.2, 10.9, 152, 9.7 and 0.92, respectively. The lambs were slaughtered when they reached about 39 kg live weight. Following slaughter, the liver was removed and weighed and the caudal lobe frozen for subsequent Cu analysis. The livers of lambs on the plastic floor treatment had higher liver weights (843 vs. 804 g, S.E.M. 11.0; P P