Níveis de aminoácidos digestíveis em dietas de frangos de corte de crescimento lento sobre deposição de nutrientes e expressão gênica

Abstract

The Brazilian poultry industry has its diets based on corn and soybean meal, ingredients that at certain times of the year may have their supply reduced, or increased with an increase in price. To reduce food costs, brewery residue is a by-product of the brewing industry with the potential for inclusion in animal feed and has an abundant supply, however, this residue has antinutritional factors for birds, but which can be reduced with the addition of enzymes exogenous substances, such as xylanase, in order to improve the nutritional intake of the diet. Thus, this study was conducted to evaluate the inclusion of brewery residue, xylanase, and reduction of metabolizable energy (ME) in slow-growing broiler chicken diets on performance and carcass traits. A total of 600-day-old male chicks of the Naked Neck strain were used, distributed in an entirely randomized design, with six treatments and five replications of 20 birds each. The diets were: balance diet (SRD) - complete nutritional requirement, without brewery waste and xylanase, reduction of energy in diet (RD) - reduction of 100Kcal/kg of metabolizable energy (ME) without brewery waste and xylanase, reduction of energy in diet with the inclusion of brewery waste in proportions of 0 (RXD), 5 (RXD5), 10 (RXD10) and 15% (RXD15) with 100g/t of xylanase. The broilers were reared in an intensive, conventional shed from 1 to 84 days. The use of brewery waste associated with xylanase enzyme in energy-reduced diets for slow-growing broilers did not affect performance at 84 days, as well as there was no difference in yields and absolute weights of cuts and carcass on the balanced diet. Therefore, the inclusion level of 15% of brewery residue associated with 100g/t of xylanase in diets with a reduction of 100kcal/kg of metabolizable energy.