A total of 1440male broiler chickens from 8 to 21 days old was assigned to two experimentsto evaluate the physical form of diet, use of enzymes and nutritional levelsof corn-soybean meal based diets. A completely randomized design as a 2 ×2 × 2 factorial scheme, two physical forms of diet (meal or crushed),with or without enzimatic complex (amylase, cellulase and protease) and twonutritional levels (95 or 100% of the recommendations), was used. In the experiment1, 1200 birds were assigned to the eight treatments with five replicates of30 chickens each, to evaluate the feed intake (FI), weight gain (WG) and feedconversion (FC). The experiment 2 was carried out simultaneously with the metabolismassay, when 240 birds were allotted to eight experimental treatments with sixreplicates of five birds each. The total excreta collection started at 18 daysof age, once a day for three consecutive days, to determine the metabolizableenergy (AMEn) and the metabolizability coefficients of dry matter (MCDM), crudeprotein (MCCP) and ether extract of the experimental diets. The dietary physicalform and nutritional level affected feed intake, but not weight gain. Dietarynutritional level × physical form interaction on AMEn and metabolizabilityof the dry matter and crude protein was also observed. The physical form improvesenergy and MCDM while the enzymes influence the metabolizability of dry matterand crude protein. Except for MCCP, the other characteristics are influencedby the dietary nutritional level.
