Enzyme Supplementation of Broiler Feeds with Reduced Mineral and Energy Levels

ABSTRACT

An experiment was conducted with the purpose of evaluatingenzyme blends on the performance, carcass traits, and bonemineralization of broilers. In total, 928 one-day-old Cobb 500 malechicks of were used. A completely randomized design with fourtreatments with eight replicates of 29 birds each was adopted. Theevaluated treatments were 1- Positive Control (PC), feed containingthe nutritional recommendations of the genetic companys manual; 2-Negative Control (NC), feed with reductions of 75 kcal/kg AME and0.10 and 0.12 percent points of phosphorus and calcium, respectively;3 - NC + enzyme blend (amylase + β-glucanase, xylanase, and phytase;250 g/t of feed) and 4 - NC + enzyme complex (phytase, amylase,xylanase, glucanase, pectinase, cellulase, and protease; 200 g/t offeed). Birds fed the diet with reduced nutrient levels (NC) presentedthe worst performance (p<0.05). The supplementation of the enzymeblend promoted similar (p<0.05) weight gain and feed conversion ratioas those obtained with the PC diet during the period of 1-21 daysof age. During the phase of 22-42 days and the entire experimentalperiod, weight gain and feed conversion ratio improved with the use ofthe enzyme combinations compared with the NC group, but remainedlower than the PC group. Enzymes combinations did not affect (p>0.05)carcass or parts yields. The broilers fed the reduced-nutrient and energydiet presented lower (p<0.05) tibial ash, calcium, and phosphoruscontents that the other treatments. The use of enzyme combinationsimproved the performance of broilers fed diets with reduced nutrientand energy levels.(AU)