Fermentação em estado sólido de coprodutos de milho para suínos em crescimento

Abstract

The use of corn as a raw material for ethanol production has grown significantly in Brazil due to the availability of the raw material and the concern with the emission of greenhouse gases. However, the presence of non-starch polysaccharides (NSPs) in dry distillers grains with solubles (DDGS) leads to a limitation for the efficiency of nutrient utilization and inclusion in diets for monogastric animals. The solid-state fermentation process (SSF) consists of the growth of microorganisms in solid materials containing sufficient moisture to support microbial growth, in which it synthesizes enzymes capable of degrading the substrate to obtain nutrients for cellular metabolism. The use of SSF for animal feed promotes increased protein digestibility, production of short-chain fatty acids, digestibility of NSPs, improvements in intestinal health and reduction of antinutritional effects. Therefore, the objective was to prospect bacterial strains capable of modifying the fibers of corn DDGS submitted to a solid state fermentation process and to evaluate the effects of using fermented DDGS on digestibility, nitrogen balance and biochemical and oxidative stress parameters in growing pigs. 37 bacterial strains were isolated from soil samples from the Cerrado-Amazonian transition region with fiber degradation capacity, 5 were selected through solid state fermentation tests, for presenting higher enzymatic index (EI) and enzymatic production coefficient (EPC). The fermentation assays indicated significant changes in the bromatological values of mineral matter (MM) non-protein nitrogen (NNP) and insoluble fiber in neutral detergent (NDF), neutral detergent insoluble crude protein (NDICP), acid detergent insoluble crude protein (ADICP) and soluble carbohydrates (SCs). A digestibility trial with castrated male pigs with initial body weight of 24.7±4.61 kg showed a reduction in MM digestibility and an increase in NDF digestibility and nitrogen metabolizability coefficient, an increase of up to 78.21 kcal/kg of digestible energy and 72.79 kcal/kg of metabolizable energy for the 10EA2 bacteria, without causing impacts on feed efficiency and oxidative stress and biochemical parameters of the blood of growing pigs.