Adição de xilanase em diferentes níveis de energia metabolizável em rações para frangos de corte

Abstract

To evaluate the supplementation of xylanase enzyme in diets containing different levels of metabolizable energy (ME) for broilers 1-44 days on the performance, carcass characteristics, intestinal morphology, bone characteristics and economic viability. Used 2,000 Coob500 broilers distributed in a completely randomized design in a 2x5 factorial arrangement (whether or not the xylanase enzyme and five levels of EM), divided into ten treatments with eight replicates of twenty-five broilers per each. We conducted analysis of variance and means separated by the Tukey test at 5% probability. To determine the levels of ME used regression analysis. As there was an increase in the levels of ME in all diets feed intake (FI) decreases linearly, weight gain (WG) and feed conversion (FC) were improved, positive behavior was also observed in bone strength, ash content of tibia, height villo, crypt depth and villus:crypt. The xylanase provided improvements in WG and animal FC at all stages, increased animal carcass yield and also increased the villus:crypt. The enzyme provided less deposition of minerals in the tibias in broilers. There was interaction between diet ME levels with the addition of the enzyme on the WG and FC in animal 1 to 35 days, intestinal morphology and bone characteristics being that the action of the enzyme minimized when there was an increase of ME with oil addition soybeans. It is recommended use of xylanase in diets composed by corn and soybeans and levels of 3,075, 3,200 and 3,225 kcal / kg of ME for broilers in the initial phase, growing and finishing, respectively.