Influence of physical form and energy level of the diet on performance and carcass composition of broilers

Brazilian broiler production still debates the use of pelleted or mash diets. Therefore, an experiment was conducted to investigate the influence of dietary energy level (2.8, 2.9, 3.0, 3.1, and 3.2 Mcal EM/kg) and physical form (pellet, without fines; and mash) on performance and carcass composition, of 3 200 male broilers, from 22 to 43 days of age. The fines from the pelleted diet had higher calcium and phosphorus levels than the whole pellets. Intake of pelleted diets was greater (P<.05) for energy levels below 3.1 Mcal EM/kg. The energy levels did not influence weight gain, but grains were greater with pelleted than with mash diets (1.82 vs. 1.69 kg). Higher levels of energy resulted in better feed conversion ratio (P<.01), but there were no differences in caloric conversion ratio (P<.05). Pellet diets resulted in better feed (1.93 vs. 2.04) and caloric (5 791 vs. 6 115 kcal/kg) conversion (P<.01), but greater carcass fatness was also observed (abdominal and gizzard fat) (P<.01) and higher mortality rate (17.8 vs. 8.3 %) (P<.01) for pellet and mash diets, respectively