Feed Consumption in Relation to Dietary Bulk and Energy Level : The Effect of Surgical Removal of the Crop

RECENT years have seen a renewed interest in the energy requirements of chickens. Before the introduction of the high energy broiler ration by Scott et al. (1947) little attention was paid to energy levels and to the bulk (indigestible matter) content of poultry rations, with the result that most older type rations were high in bulk, low in energy, and were usually less efficiently utilized. Since 1947 we have been moving in the opposite direction: decreasing the bulkiness of our diets and concommitantly increasing the energy and efficiency of utilization. This past year has seen the use of fats in poultry rations to further increase the energy content and possibly the efficiency of utilization as well. The concept of bulk (indigestible matter) and feed volume (dry matter) was introduced by Lehmann (Scharrer, 1951), who pointed out their importance in relation to satisfying the animal’s need in two ways: first, the physiological …