It was studied the effect of soybean meal (SBM) composition, varying in CP (SBM44%, SBM46% and SBM48%), on performance, metabolism and intestinal micrometry of broilers. Three SBM were produced from the SBM with 48.4% CP and increasing levels of toasted soybean hulls. Three hundred and twelve birds were assigned to three treatments with eight replicates. The diets were formulated for three periods: 1 to 7 days, 8 to 21 days and 22 to 42 days of age. All dietary treatments were isoenergy and isoprotein. From 1 to 7 days of age, no treatment effect on bird performance was observed. However, from 8 to 21 days of age, the birds fed SBM48% showed the best weight gain (WG) and feed conversion (FC). In the period from 1 to 21 days of age, the broilers fed SBM48% showed higher body weight and WG and better FC than those fed SBM44%. In the period from 22 to 42 days of age, the birds on all dietary treatments showed similar performance. The metabolism parameters evaluated at both periods (3 to 7 and 39 to 42 days of age) showed that the SBM48% treatment promoted a significantly higher coefficient of metabolizability of GE and DM than SBM44% treatment. No treatment effect on villi height, cript depth and number of intestinal villi was observed.
dry matter metabolizability; duodenal morphometry; energy metabolizability
