An experiment was conducted to evaluate the performance and composition of litter, tibia, liver and excreta of broiler chicks at different phases using different levels of available phosphorous (Pd) and the enzyme phytase. One thousand and two hundred one-day-Cobb-male chicks were used, distributed in a randomized complete design, using a 4 × 3 factorial arrangement, consisting of four available phosphorus levels and three phytase levels - 0, 500 and 1,000 FTU phytase/kg of diet with four replications of 25 birds each. The levels of available phosphorus were obtained considering four different availabilities of total phosphorus (Pt), corn and soybean meal (34, 56, 78 and 100% availability). The performance indices were evaluated at the end of each breeding phase and at the age of 42 days. The performance parameters were affected by the reduction in available phosphorus levels in the diets and the reduction of this element to levels below 19% affected negatively the performance and the use of phytase in available phosphorus level reduced in 39% improved the performance of the broilers. In the growing phases, reduction in the available phosphorus content using the phytase enzyme influenced the performance and the litter and bone characteristics.
breeding viability; feed intake; productive efficiency index; viability; weight gain
