The objective of the present investigation was to study the effects of glutamic acid on repairing intestinal injury and improving anti-oxidative ability in piglets challenged with DON.A total of 28 piglets (Duroc×Landrace×Large Yorkshire strain) were assigned randomly into 4 groups (7 pigs/group): fed with uncontaminated basal diet (NC),4mg/kg deoxynivalenol-contaminated diet (DON),4mg/kg deoxynivalenol diet + 2% glutamic acid (DG),or uncontaminated diet + 2% glutamic acid (Glu),respectively.A 15,30 and 37 days post treatment,blood samples were collected for determining the concentrations of CAT,T-AOC,H202,NO,MDA,DAO and D-lactate.At the end of the study,all piglets were slaughtered to collect kidney,liver and small intestine for detecting the concentrations of H202,MDA,and DAO,and analyzing the intestinal morphology and Akt-mTOR signaling pathway.Our results clearly showed that DON significantly (P<0.5) decreased antioxidant activity in blood serum,kidney,liver and intestines,increased the levels of D-lactate and DAO in blood plasma,whereas the levels of MDA,D-lactate and DAO in DG and Glu group were significant (P<0.05) lower than those in NC and DON group.Meanwhile,crypth depth and goblet cell number in jejunum in DG group were significantly (P<0.05) lower than those in DON group.Also,the villus height in ileum in DG group were significantly (P<0.05) higher than those in DON group.Other compelling results indicated that DON significantly (P<0.05) decreased the relative protein expression levels of 4EBP1,phosphorylated 4EBP1,Akt,phosphorylated Akt,and mTOR in ileum and jejunum,while the protein expressioin levels of 4EBP1 and phosphorylated Akt in ileum,and 4EBP1,phosphorylated 4EBP1,phosphorylated Akt,and mTOR in jejunum were significantly (P<0.05) increased in DG group.These findings indicated that DON could cause oxidative injury,intestinal permeability enhancement,epithelial cell apoptosis and protein synthesis inhibition,whereas glutamic acid supplementation enhanced intestinal integrity,promoted the intestinal epithelial cell proliferation and protein synthesis,suggesting the repairing effects of glutamic acid on liver and kidney oxidative stress,especially intestinal injury induced by DON.To our knowledge,this is the first report that studied the protective effects by glutamic acid on DON-induced toxicity in piglets.Our findings support the notion that moderate amounts of dietary glutamic acid have important implications for nutritional support of piglets.