INFLUENCE OF ENERGY SOURCE AND PHYSICAL FORM OF ALL-CONCENTRATE RATIONS ON EARLY WEANED LAMBS

Abstract

Barley and wheat were compared as energy sources in all-concentrate rations for lambs weaned at 8 wk of age. The cereal grains were fed in the whole, rolled, and pelleted forms, together with a pelleted protein–mineral–vitamin supplement. Digestibility trials were also conducted to measure the digestibility of energy and protein as influenced by grain, process, and level of intake. There was no significant difference (P > 0.05) in growth rate of lambs fed wheat or barley. Whole grains resulted in a significantly (P < 0.05) faster rate of gain than the pelleted form. Digestibility of energy was not influenced by the method of processing, indicating that the lambs digested the whole grains as efficiently as the processed forms. Protein digestibility was similar for the whole and rolled grains with a tendency for pelleting to depress digestibility of this nutrient. Increasing feed intake from maintenance to appetite resulted in a slight but significant (P < 0.05) depression in nutrient digestibility. The results of this study suggest that processing cereal grains for lambs is unnecessary from the standpoint of digestibility and would appear to be detrimental in terms of growth rate and feed conversion efficiency.