Effects of Fermented Soybean Meal on Growth Performance,Serum Biochemical Indices,Mucosal Immune Function and Microorganism in Yellow-Feathered Broilers

This experiment was conducted to investigate the effects of fermented soybean meal on growth performance,serum biochemical indices,mucosal immune function and microorganism in yellow-feathered broilers.A total of 250 one-day-old yellow-feathered broilers were randomly divided into five groups,and each group included five replicates(10 broilers per replicate).Control group(group Ⅰ) was fed a basal diet.Group Ⅱ was fed the basal diet supplemented with 15% zinc bacitracin 200 mg/kg and 10% colistin sulfate 60 mg/kg.The treatment groups(groups Ⅲ,Ⅳ,Ⅴ) were fed the basal diet replaced some of common soybean meal with 3%,6% and 9% fermented soybean meal,respectively.The experiment lasted for 28 days.The results showed as follows: 1) compared with group Ⅰ,the body weight gain of groups Ⅳ and Ⅴ was significantly increased by 3.87% and 4.38%(P0.05),respectively;the feed/gain of groups Ⅳ and Ⅴ was significantly reduced by 4.75%(P0.05) and 5.71%(P0.05),respectively;the rate of survival of group Ⅴ was significantly increased by 6.38%(P0.01).2) The activity of alkaline phosphatase in serum of groups Ⅱ and Ⅴ was significantly higher than that of group Ⅰ(P0.05),uric acid content in serum of group Ⅴ was significantly lower than that of group Ⅰ(P0.05),and the other groups were no significant differences(P0.05).3) Compared with group Ⅰ,duodenum villus height of groups Ⅱ,Ⅲ,Ⅳ and Ⅴ was significantly higher than that of group Ⅰ(P0.01),and group Ⅴ was the highest.The number of mast cells of group Ⅴ was significantly decreased compared with group Ⅰ(P0.01).The number of secretory immunoglobulin A(sIgA) positive cells of groups Ⅱ,Ⅲ,Ⅳ and Ⅴ was significantly increased compared with group Ⅰ(P0.01),and group Ⅴ was the highest in all.4) The number of Escherichia coli of groups Ⅱ and Ⅴ was significantly lower than that of groups Ⅰ,Ⅲ and Ⅳ(P0.05),and the number of Lactobacillus of group Ⅴ was significantly increased compared with group Ⅰ(P0.05).It is concluded that fermented soybean meal can improve the body weight gain and the activity of alkaline phosphatase in serum,decrease feed/gain and uric acid content in serum,increase duodenal villus height,make the number of mast cells and sIgA-positive cells stable and intestinal micro environment better,reduce the number of Escherichia coli in cecum,and increase the number of Lactobacillus in yellow-feathered broilers and the best replacement rate in prior period is 9%.