Effects of supplementary feeding on growth and carcass characteristics of fat-tailed lambs grazing cereal stubble

Abstract

Despite a shortage of animal feed in Iran, cereal stubble is often underutilized due to agro-economic reasons. On the other hand, lambs fed with a conventional fattening ration deposit a considerable amount of fat; therefore, this experiment was conducted aimed at better utilization of cereal stubble and reducing the fat content of lamb carcasses. Fat-tailed Mehraban and Ghezel ram lambs were put on four feeding systems (FS) for 100 days. Animals in one group (FS1) were lot-fed with a conventional fattening ration (4% of the mean body weight) consisting of 50% ground barley and 50% chopped alfalfa hay. FS2, FS3 and FS4 animals grazed stubbles, and in the evening, received 2% of their body weights either ground barley (FS2), a mixture (50:50 DM basis) of ground barley and alfalfa hay (FS3), or ground alfalfa hay (FS4). Daily gain, slaughter weight, and tail weight were greatest (P