Grãos secos de destilaria de alta proteína e enzimas exógenas na alimentação de frangos de corte

Abstract

High-protein distillers dried grains (HP-DDG) are obtained from ethanol production from corn and have favorable nutritional characteristics for use in animal feed. However, this coproduct has a considerable amount of non-starch polysaccharides, which makes the use of exogenous enzymes relevant. In this way, this study evaluated HP-DDG levels and the association of exogenous enzymes (amylase and protease) in diets for broiler chickens and the influence on performance and gut health. A total of 880 male broilers, one day old, were randomly allocated to five treatments, including a reference diet based on corn and soybean meal and diets with HP-DDG (5% and 7.5%), with or without the inclusion of amylase and protease considering nutrient matrix values, with eight replicates and 22 birds/each. At 10, 21, 35, and 42 d, weight gain (WG), average feed intake (AFI), and feed conversion ratio (FCR) were determined. At 21 d, one bird/replication was selected to evaluate intestinal permeability by gavage with fluorescein isothiocyanate dextran (FITC-d). A fragment of the jejunum of this bird was collected to determine histopathological changes using the I See Inside® method. Concurrently, ileal content from four birds per replicate was collected to determine the digestibility coefficients of dry matter (DM), crude protein (CP), and energy, as well as digestible nutrients and digestible energy value. At 42 d, 2 birds per replicate were euthanized to determine carcass and cut yields and abdominal fat percentage. Additionally, at the end of the experimental period, the economic viability was analyzed. The data were submitted to analysis of variance, and the means were compared by Tukey's test at 5% probability. Throughout the 42-d rearing period, bird performance was similar between treatments. Intestinal permeability and histology were not affected (P>0.05) by the inclusion of HP-DDG, nor by the inclusion or exclusion of amylase and protease. In general, the birds presented similar values for digestibility coefficients and digestible nutrients and energy. Carcass and cut yields (breast, legs, wing, and tenderloin), as well as the percentage of abdominal fat, did not differ (P>0.05) between treatments. Regarding economic viability, there was a reduction in feed cost per ton of chicken produced of 2.15% and 1.77% in the treatments with the inclusion of 5% and 7.5% HP-DDG and amylase and protease enzymes compared to the reference diet. The inclusion of up to 7.5% HP-DDG in broiler diets can be employed without compromising the performance and gut health of the birds. Combining the inclusion of the coproduct with exogenous enzymes (amylase and protease) with nutritional matrix enhancement, there is a reduction in feed cost while maintaining the performance and gut health parameters of the animals.