Effects of Varying Dietary Protein and Energy Levels on Growth Rate and Body Fat of Broilers

ABSTRACT Three experiments were conducted in which the protein and energy levels were varied in an attempt to produce broiler carcasses with more acceptable fat deposition at market age. Male broilers had more abdominal fat than female broilers to 46 days of age. Females deposited abdominal fat at a rate greater than that of the males after 46 days of age. A significant percentage of the weight gain after 46 days was in the form of abdominal fat in the female. Feeding no sup-plemental fat in the diet for the first seven days resulted in a decrease in the percentage of ab-dominal fat at 49 days of age. High dietary protein levels were detrimental to growth during the starting period (0 to 14 days) but beneficial in maximizing gain and feed efficiency during the finishing period (28 to 49 days). Feeding no supplemental fat for the first 7 days of age, regardless of the energy level of the finisher, produced the least abdominal fat of all diets fed to 49 days. More abdominal fat was produced when supplemental fat was withheld for 0 to 10 days or 0 to 14 days of age