Combinações enzimáticas e seus efeitos sobre a digestibilidade de nutrientes, desempenho, morfologia intestinal e economicidade de dietas para frango de corte

Abstract

The present study was conducted to understand the effects of enzyme combinations in diets based on corn and soybean meal for broilers. Two experiments were carried out, the first to evaluate the digestibility of nutrients and the energy value of the diets. And the second to analyze the performance, carcass yield, intestinal morphology as well as to determine the effective operational cost of the diets and the economic probabilities in choosing the diets. In both trials the birds were distributed in a completely randomized design in a 2x3 factorial scheme, with dietary treatments in two dosages of 500 and 1000 FTU of Phytase / Kg (F500 and F1000) and three enzymatic combinations: phytase (F), xylanase + βglucanase (Xβ), xylanase + βglucanase + protease (XβP). All data were submitted to the analysis of the statistical package (SAS, 2001). For the processing of economic evaluation data, the effective operating cost of disbursements for diets was obtained and then for Monte Carlo simulation, risk analysis was used. The dosage of 500 FTU / kg (F500) of phytase provided better standardized digestibility coefficients (P <0.05) for some amino acids when compared to the use of the 1000 FTU / kg (F1000) level of phytase. As well as showed improvement in the integrity of intestinal morphology. There were no significant effects on carcass performance and yield with the use of different combinations. The F10002 and F1000Xβ4 rations provided the lowest costs for the initial and growth phases, respectively.