Analysis Of Nutritional Characteristics Of Wheat Bran By Solid State Fermentation And Its Application In Broilers

In this paper,the fermented wheat bran(FWB)was produced with solid-state fermentation method,and the changes of nutritional indexes before and after solid-state fermentation were analyzed.Then,Arbor Acres(AA)broilers were used to study the effects of fermented wheat bran on growth performance,serum immune function,intestinal morphology and intestinal microbial composition of broilers under bacterial lipopolysaccharide(LPS)stress.Experiment 1: Study on the production process and nutritional characteristics of wheat bran by solid state fermentationIn this experiment,wheat bran was used as raw material,and lactic acid bacteria,bacillus subtilis,saccharomyces and aspergillus fragrant were selected,and the nutritional value of fermented wheat bran was analyzed.The results showed that:(1)The morphological structure and texture of FWB on dry basis and wet basis were curled hard,fluffy and soft,with a mellow smell,and the color was wheat color and light brown,respectively.(2)Based on dry matter basis,compared with wheat bran,the contents of crude protein,acid-soluble protein,crude fat and total energy in FWB were increased by 19.89%(P < 0.05),248.29%(P < 0.05),39.41%(P < 0.05)and 8.32%(P < 0.05),respectively,and crude fiber was decreased by 7.73%(P < 0.05).Aflatoxin B1,zearalenone and deoxynivalenol were decreased by 36.36%(P < 0.05),85.62%(P < 0.05)and 3.89%(P <0.05),respectively.(3)Compared with wheat bran,the contents of total polyphenols,crude polysaccharides,soluble dietary fiber,total dietary fiber and mannan were increased by207.33%(P < 0.001),78.88%(P = 0.189),121.23%(P < 0.05),58.77%(P < 0.05)and95.65%(P < 0.001),respectively.In addition,the number of viable bacteria of lactic acid bacteria,bacillus,saccharomyces and aspergillus in wet FWB was 7.78,5.62,5.24 and 4.93 log CFU/g,respectively.Experiment 2: Effects of fermented wheat bran on growth performance,serum immune function,intestinal morphology and intestinal microorganism composition of broilers under LPS stress.The experiment adopted a 2×3 factorial experimental design,with LPS stress(intraperitoneal injection of 0.5 ml 500 μg/kg LPS or saline)and diet type(basal diet,dry FWB and wet FWB)as treatment factors.A total of 252 healthy one-day-old AA male broilers were randomly divided into 6 treatment groups with 6 replicates per group and 7broilers per replicate.The treatment groups were: the basal diet +LPS/saline,7% dry FWB group +LPS/saline and 7% wet FWB group +LPS/saline.The experiment was divided into three stages: the early stage(1～16 days old),the LPS stress treatment stage(17～21 days old,injection of the same dose of LPS or saline on the 16 th,18th,and 20 th days of age)and the late stage(22～42 days old).The results showed as follows:(1)There was no significant difference in growth performance between and within the dry FWB and wet FWB groups at the early stage of experiment(P > 0.05);Compared with basal diet group,FWB could increase average body weight(ABW),average daily gain(ADG)and average daily feed intake(ADFI)of broilers(P < 0.05),but had no significant effect on feed conversion rate(FCR)(P > 0.05).(2)During LPS stress treatment stage and later stage,LPS stress significantly decreased ADG,ADFI and FCR of broilers at 21 days of age(P < 0.05);Compared with basal diet group,FWB groups significantly increased ADG and ADFI of broilers at 21 and 42 days of age(P < 0.05),but had no significant effect on FCR,and the effect of wet FWB were better than dry FWB.(3)LPS stress had no significant effects on the morphological structure of jejunum and ileum of broilers at 21 days of age(P > 0.05),but dry FWB and wet FWB significantly increased the villus height and villus to crypt depth ratio of ileum of broilers at 21 days of age(P < 0.05),and had a tendency to decrease the jejunum crypt depth of broilers at 42 days of age(P = 0.101).There was no significant difference between the dry FWB and wet FWB groups.(4)LPS stress significantly increased the E.coli number of caecum chyme on days 21(P < 0.05);feeding FWB can significantly reduce the E.coli number on days 42(P < 0.05),but had no significant effect on the number of cecum lactobacillus and bifidobacterium on days 21 and 42(P > 0.05);There was no significant difference between wet FWB and dry FWB groups.(5)LPS stress had no significant effects on serum total protein(TP),albumin(ALB),globulin(GLB),total cholesterol(TC),triglyceride(TG),glucose(GLU),aspartate aminotransferase(AST)and alanine aminotransferase(ALT)of broilers at 21 and 42 days(P > 0.05).Feeding FWB significantly increased serum TP,ALB,GLB,GLU and AST of broilers at 21 days of age(P< 0.05),while feeding wet FWB significantly decreased serum TP,AST and ALT of broilers at 42 days of age(P < 0.05).There was no significant difference between dry FWB groups and wet FWB groups.(6)LPS stress treatment had no significant effects on serum immunoglobulin A(Ig A),G(Ig G)and M(Ig M)of broilers at 21 days of age(P > 0.05),but feeding wet FWB significantly increased serum Ig A,Ig G and Ig M levels of LPS-stress broilers(P < 0.05),and the effect of wet FWB groups was better than dry FWB groups.(7)LPS stress had different effects on serum immune cytokines tumor necrosis factor(TNF)-α(P < 0.05),interleukin(IL)-2(P = 0.08),IL-1β(P = 0.07),acute C-reactive protein(CRP)(P= 0.05)and IL-10(P = 0.07)of broilers at 21 days of age.The levels of serum pro-inflammatory cytokines IL-2,IL-6,IL-8,IL-1β and CRP of broilers in LPS stress groups were significantly decreased on days 21 and 42(P < 0.05),and the levels of anti-inflammatory cytokines IL-13 also was significantly decreased(P < 0.05),but IL-4 and L-10 were significantly increased(P < 0.05).The effect of wet FWB was better than dry FWB.The levels of pro-inflammatory factors TNF-α and IL-8 in broilers in all treatment groups were significantly decreased on days 42(P < 0.05).In conclusion,the solid-state fermentation of lactic acid bacteria,bacillus subtilis,saccharomyces and aspergillus fragrant can effectively improve the nutritional value of wheat bran.The addition of FWB can alleviate the growth inhibition of LPS stress on broilers by regulating the levels of pro-inflammatory and anti-inflammatory cytokines,improving intestinal tissue morphology and flora composition,and enhance the body’s immunity,and the effects of wet FWB were better than dry FWB.The results of this experiment provided a reference for the application of fermented wheat bran in the diet formulation of broilers.