Dietary L-arginine Supplementation Improves Intestinal Function in Weaned Pigs after an Escherichia coli Lipopolysaccharide Challenge

This study was conducted to determine whether L-arginine (Arg) supplementation could improve intestinal function in weaned pig; after an Escherichia coli lipopolysaccharide (LPS) challenge. Treatments included: i) non-challenged control (CONTR, pigs fed a control diet and injected with sterile saline); ii) LPS-challenged control (LPS.. pigs fed the same control diet and challenged by injection with Escherichia coli LPS); iii) LPS+0.5% Arg (pigs fed a 0.5% Arg diet and challenged with LPS); and iv) LPS+1.0% Arg (pigs fed a ..0% Arg diet and challenged wit h LPS). On d 16, pigs were administrated with LPS or sterile saline. D-xylose was orally administrated at 2 h following LPS challenge, and blood samples were collected at 3 h following I-PS challenge. At 6 h post-challenge, pigs were sucrificed and intestinal mucosa samples were collected. Supplementation of Arg attenuated LPS-induced damage in gut digestive and barrier functions, as indicated by an increase in ileal lactase activity, and duodenal and ileal diamine oxidase activities (p<0.05). Arg administration also prevented the increase of jejunal malondialdehyde content and the decrease of ileal superoxide dismutase activity by LPS challenge (p<0.05). Furthermore, the jejunal nitric oxide level and inducible nitric oxide synthase activity were also) improved after Arg supplementation (p<0.05). These results indicate that Arg supplementation has beneficial effects in alleviating he impairment of gut function induced by LPS challenge.