Exoenzima protease em rações base sorgo grão inteiro ou moído em dietas para frangos de corte e galinhas poedeiras

Abstract

The reduction in production costs and the search for better digestibility of the nutrients present in cereal grains are constant in poultry. The objective of this work was to evaluate the inclusion of exoenzyme protease in ground or whole grain sorghum diets for laying hens and broilers on performance, energy and digestibility of nutrients. Two experiments were carried out: Experiment 1 was developed in a completely randomized design, consisting of five diets: corn (M), ground sorghum (SM), whole sorghum (SI), ground sorghum with protease (SMP) and whole sorghum with protease (SIP), with six replications, total of 150 hens, housed in number of five birds per cage. At 23 days of experiment, the digestibility test was performed and at the end of the 28-day cycle, the parameters of productivity, quality and subsequent bromatological composition of the eggs were determined. The laying percentage was higher in birds that received diets with protease and the feed conversion per egg mass was better for the treatment in SMP, with no difference between the treatments SIP and M. Regarding egg quality, the diets M and SMP provided greater Haugh unity. Higher content of ether extract in the yolk was observed in eggs of birds that received SI and SIP diets and a higher percentage of mineral matter in the albumen was provided by the SMP diet. There was no difference for the variables apparent metabolizable energy and corrected for nitrogen balance (EMA and EMAn) between treatments. The higher digestibility of crude protein (DPB) was provided by the SIP diet, which also had a lower production cost. It is concluded that the use of exoenzyme protease in sorghum-based diets improves the parameters of production, quality and composition of eggs and digestibility of laying hens. Experiment 2 was carried out in a completely randomized design, with four treatments with ten repetitions, each box with 20 birds (males and females), totaling 800 birds of the Cobb Slow strain. The treatments were ration: SM, SI, SMP and SIP. At 22 days of age, a digestibility assay was performed consisting of four treatments and six repetitions to determine the values of EMA, EMAn, DPB and DEE (digestibility of the ether extract) and at 28 and 42 days of age were measured: live weight (PV), feed intake (CR), feed conversion (AC). There was no difference for the values of EMA, EMAn and DEE in the tested diets. DPB was better in diets with added protease. Regarding performance at 28 days of age, the SMP diet provided greater PV and SIP provided better CA in birds compared to the SM diet. At 42 days of age the performance parameters analyzed were the same in the tested diets. It is concluded that the addition of protease in diets based on whole or ground sorghum did not influence energy, but improved the performance of broilers at 28 days of age, pointing out that there was a greater digestibility of crude protein from the ground diet with protease. Whole grain sorghum together with exoenzyme protease is nutritionally and economically viable in the nutrition of laying hens and broilers.