The Combination of Different Dietary Fiber Sources Improves the Growth Performance, Nutrient Digestibility and...

This experiment was conducted to investigate the effects of combinations of different dietary fiber sources (inulin and cellulose) on broilers from 1 to 42 d of age. A total of 560 Arbor Acres male broilers were randomly divided into seven dietary treatments with eight replicates per treatment and 10 broilers per replicate. A con-soybean control (CON) diet, CON diet supplemented with antibiotics (zinc bacitracin, 50 mg/kg, AB diet), CON diet diluted with 2% of inulin (LNU), CON diet diluted with 1.5% of inulin and 0.5% of cellulose (MIX1), CON diet diluted with 1.0% of inulin and 1.0% of cellulose (MIX2), CON diet diluted with 0.5% of inulin and 1.5% of cellulose (MIX3), and CON diet diluted with 2.0% of cellulose (CEL). Results demonstrated body weight (BW) (d42) and average daily gain (ADG) (d1 to 21, d22 to 42, d1 to 42) were significantly increased (p < 0.05), and the feed-to-gain ratio (F/G) (d1 to 21, d22 to 42, d1 to 42) was markedly decreased (p < 0.01) in the MIX1 group than those in the other treatments. Compared to broilers fed CON, AB, or other diets, broilers fed with the MIX1 diet had markedly improved (p < 0.05) nutrients utilization, lactase and superoxide dismutase (SOD) activities, and mRNA expression levels of jejunal function-related genes (SGLT1, GLUT2, PepT1, GLP-2, and ZO-1), while significantly decreased (p < 0.05) intestinal pH, TNF-α content and IL-6 mRNA level in jejunum at 21 or 42 days of age. Collectively, dietary fiber was included in broiler diets at a total level of 2%, and the MIX1 combination (combining 1.5% of inulin and 0.5% of cellulose) promoted growth performance, nutrient digestibility, and intestinal function, and this diet may be a potential alternative to antibiotics.