Effects Of Glutamine On Immune Regulation And Molecular Mechanism Of Weaned Piglets

The thesis is researching the performance on growth of weaned piglets with glutamine supplementation dietary,immune regulation and its mechanism.Using the2*2 factorial design,selection of 64 weaned piglets,were randomly divided into 4 groups,with 4 replicates of 4 pigs per replicate.Using 2*2 factorial design,diet type(basal diet or 1.2%glutamine diets)and stress type(LPS or physiological saline injection).The experiment lasted for 28 days.?,? group were fed the basal diet,respectively at the 14d and 21d were injected with saline and LPS configuration solution(100 g/kg BW);group ?,? Group 1.2%glutamine supplementation in diets,respectively in the 14d and 21d intraperitoneal injection of saline solution and LPS configuration(100 g/kg BW).Each treatment group of the day after injection for 3 hours after blood samples were collected and separated serum.In the test section 29d of the slaughter,blood,serum separation,change determination of serum immunoglobulin and cytokines.At the same time,piglets thymus,spleen and intestinal mucosa(duodenum,jejunum,ileum,TLR4),using fluorescence quantitative PCR detection in HSP70,MMP-2,MMP-9 gene in the difference in the expression of different treatment groups.The control group was set up in this study:1.LPS stress reduced the production performance of piglets,resulting in the feed gain ratio and diarrhea rate increased significantly(P<0.05).The fourteenth day of the experiment,the diet supplemented with 1.2%glutamine significantly increased the daily gain of piglets(P<0.05),reduced feed conversion ratio(P<0.05)and diarrhea rate(P<0.05);test for fourteenth days and 21 days,the effects of glutamine on the weight gain and LPS interaction effects,which alleviated LPS induced glutamine weight gain of piglets decreased(P<0.05),glutamine supplementation dietary does not exist on the effect of feed conversion ratio and diarrhea rate and the stimulation of LPS interactive effect.2.LPS stress significantly increased the stress levels.Creatine kinase 14 day old weaned piglets serum test after injection of LPS was significantly improved(P<0.05).The increase in cortisol in serum for fourteenth days and 21 days(P<0.05);and 1.2%glutamine supplementation in the diet after weaning on the content of creatine kinase in the same test period of piglet serum decreased,glucose content increased significantly(P<0.01).Glutamine and LPS stress treatment interaction only at the age of 14 days on the activity of creatine kinase by significant effect,there is no interaction of glucose and cortiol.3.With 1.2%glutamine supplementation in diet significantly immune performance in experiment fourteenth and 21 days were significantly increased IgA and IgM levels in serum of weaning piglets(P<0.05).The addition of glutamine LPS stress on IgA,IgM significantly reduced the inhibition(P<0.05).The addition of glutamine significantly improve the 14 day old IFN-levels(P<0.05),to mitigate effects of LPS stress on FN-gamma(P<0.05),while decreased the value of TNF-alpha(P<0.05).Under LPS stress,the test On the 14 day,the level of complement was significantly lower than that of the complement of the twenty-first day(P<0.05).The interaction of glutamine and LPS had no significant effect on complement 3 and complement 4.4.LPS stress that the body of interleukin level.After injection of LPS IL-6,weaned piglets serum IL-8,IL-10 were significantly increased(P<0.05),the addition of glutamine to alleviate interleukin LPS stress hormone levels increase.Effects of glutamine and LPS on interleukin three stress interaction was not significant.5.Dietary supplementation of glutamine,in experiment fourteenth and 21 days,significantly enhance the content of GSH in serum(P<0.05);LPS stress on ROS and NO levels were significantly increased(P<0.05).Glutamine and LPS stress interaction on GSH,ROS and NO levels had no significant effect.6.Thymus of piglets,HSP70 of TLR4,spleen and intestinal tissue,and expression of MMP-9 gene were determined.The analysis results showed that the diet added 1.2%glutamine can significantly improve the thymus of piglets,expression of HSP70 gene in spleen and intestinal tissues(P<0.05),significantly reduced the expression level of MMP-2 and MMP-9 TLR4.The(P<0.05).LPS stress group TLR4,MMP-2 and MMP-9 genes were significantly increased(P<0.05),caused by inflammatory reaction.The basal diet with LPS stress interaction on T LR4,HSP70 expression was significant or very significant difference(P<0.05,P<0.01)The results of this study showed that dietary supplementation of glutamine can enhance weaned piglets to improve production performance and immune function of piglets,improve the antioxidant capacity of glutamine.Alleviate the immune induced growth inhibition may be related to the increase of the expression of HSP70,decreased TLR4 and MMPs gene expression,thereby reducing inflammatory cytokine secretion.