Effects And Mechanism Of Tannins And Gallic Acid On Growth Performance And Antioxidant Function Of Broilers Fed Diets Containing Aflatoxin B₁

This study was conducted to evaluate the effects and mechanism of tannic acid（TA）and gallic acid（GA）on growth performance and antioxidant function of broilers fed a diet containing aflatoxin B₁（AFB₁）.A total of 400 1-day-old Ross 308 broilers were tested using a 2×2×2 factorial design,randomly divided into 8 groups,5repetitions per group（column）,10/treatment.Theexperimental groups were:1):control group;2):TA group;3):GA group;4):TA+GA group;5):AFB₁group;6):AFB₁+TA Group;7):AFB₁+GA group;8):AFB₁+TA+GA group.During the experiment,the addition of AFB₁was 1 mg/kg,and the addition of TA and GA was250 mg/kg.The experiment lasted 42 days,and slaughtering and sampling were carried out on days 21 and 42,respectively.The test results showed that:1.When adding AFB₁to the diet:compared with treatments without AFB₁,（1）no effect was observed on the growth performance of broilers（P>0.05）.（2）The organ indexes of liver and kidney were increased significantly at 21 and 42 days of age（P<0.05）.（3）The contents of TB,TC,TG,Glu and LDL in plasma at day 21 and TC,HDL and LDL in plasma at day 42 were increased significantly（P<0.05）.（4）The villus height,villus height/crypt depth ratio of jejunum and ileum at day 21 and the villus height/recess depth ratio of ileum at day 42were decreased significantly（P<0.05）,and the ileal recess depth was increased significantly（P<0.05）.（5）The activities of plasma cat,liver T-AOC,GST,GSH-Px and T-SOD,duodenal cat and GSH-Px,jejunal GSH-Px on day 42 plasma GST and CAT,liver T-AOC and GST,duodenal CAT,jejunal GSH-Px and ileal GST were decreased significantly（P<0.05）,and the contents of MDA in plasma on day 42 and ileum on day 21 were increased significantly（P<0.05）.（6）Significantly up regulated the relative m RNA expression of Keap1,Nrf2,NQO1,p38,JNK and CYP1A1 in liver on day 21,Keap1,Nrf2,NQO1,p38,JNK,ERK,CYP1A1,CYP1A2,CYP2A6,CYP3A4,CYP2 and CYP2H1 in jejunum,JNK and Keap1 in jejunum and CYP1A1 in liver on day 42（P<0.05）.2.When adding TA to the diet:compared with not adding TA,（1）It had no effect on the growth performance of broilers（P>0.05）.（2）The liver organ index at day 21and the kidney organ index on day 21 and 42 were decreased significantly（P<0.05）.（3）The content of plasma LDL was increased significantly at 21 days of age（P<0.05）,and the content of plasma GGT was decreased significantly at 42 days of age（P<0.05）.（4）The ratio of duodenal villus height/crypt depth was increased significantly on day 21（P<0.05）.（5）The activities of GST and ileal T-SOD in plasma and liver on day 21 were significantly increased,the activities of CAT,GST,GSH-Px and duodenal GST on day 42 were significantly increased（P<0.05）,and the content of MDA in plasma on day 42 was significantly decreased（P<0.05）.（6）The relative m RNA expressions of CYP3A4 and Keap1 liver on day 21 and Nrf2,GLRX2,p38and JNK in liver on day 42 were significantly up-regulated（P<0.05）.3.When adding GA to the diet:compared with not adding GA,（1）It had no effect on the growth performance of broilers（P>0.05）.（2）The organ indexes of liver and kidney decreased significantly at 21 and 42 days of age（P<0.05）.（3）The contents of TC,TG in plasma on day 21 and TG and LDL in plasma on day 42 were increased significantly（P<0.05）（4）the ratio of jejunal villus height/crypt depth and the height of twelve fingers and ileal villus increased significantly on day 21（P<0.05）.（5）The activities of plasma GST,and GSH-Px,liver GST,duodenal GSH-Px,jejunal T-SOD and ileal cat on day 21,plasma and duodenal GST,liver,jejunum and ileal cat on day 42 were increased significantly（P<0.05）,and the contents of MDA in jejunum at day 42,plasma,duodenum and ileum on day 21 were decreased significantly（P<0.05）.（6）The relative m RNA expressions of p38,JNK,ERK,Keap1,Nrf2,GLRX2,CYP2H1 and jejunal Keap1 in liver on day 21 and Keap1,Nrf2,NQO1,GLRX2,jejunal p38,JNK and CYP1A1 in liver on day 42 were significantly up-regulated（P<0.05）.4.Interaction between TA and GA:Compared with no TA and GA,（1）the relative m RNA expressions of Nrf2,GLRX2,ERK and CYP1A1 in jejunum on day42 were up-regulated by TA and GA（P<0.05）.（2）The addition of TA or GA could increase the activities of cat and GSH PX in liver on day 21（P<0.05）,and up regulate the relative expression of keap,ERK and cay2h1 m RNA in jejunum on day 21（P<0.05）.（3）The addition of GA alone increased the activities of jejunal T-AOC and T-SOD at 21 days of age,jejunal T-SOD and plasma GST at day 42（P<0.05）.5.Interaction between TA and AFB₁:In the diet containing AFB₁,the addition of TA increased the contents of plasma AST and TC at 42 days of age（P<0.05）,decreased the activity of duodenal T-AOC at 21 days of age（P<0.05）,and increased the relative m RNA expression of Keap1,JNK,ERK,jejunal ERK and CYP2H1 at 21days of age（P<0.05）.6.Interaction between GA and AFB₁:in the diet containing AFB₁,GA increased the content of plasma TG at 21 days of age（P<0.05）,increased the activity of plasma GSH-Px and liver cat at 21 days of age,plasma GST,liver cat and jejunum cat at 42days of age（P<0.05）,decreased the content of MDA in ileum at 21 days of age（P<0.05）,and increased the relative expression of m RNA of Keap1 and p38 in liver at21 and 42 days of age（P<0.05）,The relative m RNA expressions of CYP2H1 and CYP3A4 in 21 day old jejunum were down regulated（P<0.05）.7.Interaction of TA,GA and AFB₁:（1）in the diet containing AFB₁,the addition of TA and GA significantly decreased the organ index of liver and kidney on day 21and 42（P<0.05）,the activity of plasma GSH-Px on day 42 and the relative expression of CYP2H1 m RNA in liver at 21 days of age（P<0.05）.（2）In the diet containing AFB1,the addition of TA significantly increased the relative expression of p38 and CYP2A6 m RNA in jejunum on day 21（P<0.05）（3）in the diet containing AFB₁,the addition of GA significantly increased the relative expression of p38 m RNA in jejunum on day 42（P<0.05）.In conclusion,adding 250 mg/kg TA or GA to 1mg/kg AFB₁diet could improve the antioxidant capacity and protect health by activating p38,JNK and ERK phosphorylation and regulating Nrf2-Keap1-ARE signal pathway,and the improvement of anti-oxidation function of GA was better than that of TA.