Soluble non-starch polysaccharide modulates broiler gastrointestinal

The aim of this study was to evaluate the importance of considering dietary soluble non-starch polysaccharides (sNSP) when formulating broiler diets, due to their impact on the gastrointestinal tract environment. Cobb 500 broilers (n = 480, 80 birds per treatment) were fed either wheat-or corn-soybean meal-based diets formulated to contain either a high, medium or low sNSP content, resulting in 6 dietary treatments in a 2 pound 3 factorial arrangement of treatments. On d14 and d 35 of age, pH of the gizzard, ileum and caeca, ileum viscosity, caecal short chain fatty acid (SCFA) concentration, and ileal and caecal microbiota profile were determined. Ileal viscosity at d 35 was greater in birds fed high sNSP compared to low sNSP (P = 0.022). At both d 14 and d 35, birds fed the wheat based diet presented higher ileal viscosity (P < 0.001) and lower ileal pH (P = 0.027 and P < 0.001, respectively) compared to those fed the corn-based diet. At d 14, birds fed low sNSP exhibited higher caecal pH (P = 0.010) and propionic, isobutyric and valeric acid concentrations (P = 0.035, P = 0.007 and P = 0.011, respectively), and lower ileal Lactobacillus content (P = 0.043), compared to birds fed high sNSP. This effect was also seen for total SCFA (P = 0.017) and acetic acid (P = 0.005) concentrations in the caeca at d 14, but only in birds fed wheat-, not corn-, based diets. At d 35, total caecal SCFA concentration was greater in birds fed the wheat-based diet with high sNSP level compared to those fed the corn-based diet with high or low sNSP level (P = 0.028). In comparison to birds fed corn, birds fed wheat presented greater caecal concentrations of acetic, butyric, lactic, and succinic acids (P = 0.001, P < 0.001, P = 0.003 and P = 0.007, respectively) and Bifi- dobacteria at d 35 (P = 0.003) and succinic acid at d14 (P = 0.041). However, caecal populations of Ruminococcus and concentrations of valeric acid at d14 and isobutyric acid at d 35 were greater in birds fed the corn-compared to wheat-based diets (P = 0.043, P = 0.019 and P < 0.001, respectively). These results illustrate that dietary sNSP concentration, as well as its composition, have a direct impact on gastrointestinal viscosity and pH, and fuel beneficial microbial species, resulting in production of SCFA. It appears to be particularly important to consider sNSP level when formulating wheat-based diets for broilers.

Automated summary

This study aimed to evaluate the importance of dietary soluble non-starch polysaccharides (sNSP) in broiler diets, showing that high sNSP content can increase ileal viscosity while wheat-based diets may lead to higher ileal viscosity and lower pH. Additionally, low sNSP diets may result in lower Lactobacillus content in the ileum and higher caecal pH and short chain fatty acid concentrations, emphasizing the importance of considering sNSP level when formulating diets for broilers.