Evaluation Of The Effect Of Mannose-oligosaccharide Selenium Complex On The Repair Of Intestinal Injury In Piglets With Diarrhea Caused By Escherichia Coli

Escherichia coli is one of the most common pathogens that cause diarrhea in animals.It colonizes in the small intestine and releases adhesins and enterotoxins,resulting in diarrhea in animals,dysregulation of intestinal flora and immune response.The diarrhea of piglets caused by E.coli is often accompanied by the complex infection of other pathogens,which leads to a variety of diseases.The clinical symptoms of piglets are loss of appetite,slow growth,emasculation and even death,causing huge economic losses to the breeding industry.The classic treatment of E.coli diarrhea is antibiotics,but its disadvantages are becoming more and more obvious:drug residue,drug resistance and so on.The Ministry of Agriculture and Rural Affairs issued a notice on"banning,reducing and limiting antibiotics"in July 2019,so it is imperative to find a product that can replace antibiotics to produce good disease prevention and control effects.Therefore,this study proposed by dew oligosaccharides with sodium selenite complexation,using scanning electron microscopy(SEM),infrared spectrum,the ICP method to determine the composition,structure and content and add composition to the E.coli mode of weaned piglets feed,by recording the production performance of piglets,diarrhea,take a blood test routine blood,serum biochemical index,observing the intestinal tissue morphological structure,detection of intestinal barrier function and inflammatory factor,explore the dew oligosaccharide selenium for piglets intestinal damage repair.The results are as follows:1.MOS-Se was synthesized by chemical synthesis of mannose oligosaccharide and sodium selenite,in which the selenium content was 8.81%.The composite is obtained by lyophilization and has no regular structure.2.Se can promote feeding intake and weight gain of piglets.There was significant difference in diarrhea between E.coli challenge group(F group)and diet supplemented with selenium mannan oligosaccharide(D group)(P<0.05),diarrhea in group D was significantly lighter than that in group F;there were significant differences in blood inflammatory markers between group D and group F(P<0.05),neutrophil count and C-reactive protein in group D were significantly lower than those in group F;the villus height/crypt depth of jejunum in group D was significantly higher than that in group F(P<0.05).3.m RNA expression of tight junction protein Occludin in jejunum mucosa of piglets in group D was significantly higher than that in group F(P<0.05),CD3~+and CD4~+expression levels in group D were significantly higher than those in group F(P<0.05).The expression levels of IL-10 and IFN-γin ileal mucosa of group D were lower than those of group F(P>0.05).In summary:mannose selenium complex oligosaccharides can reduce E.coli cause blood leels of inflammatory indexes of weaned piglets,repair caused by E.coli piglet jejunum,ileum tissue pathological changes,improve the villus height/crypt depth values,improve the jejunum mucosa of Occludin,amount of m RNA expression of CD3~+,CD4~+,to reduce the IL-10 in the ileum mucosa,the expression of IFN-gamma,relieve diarrhea piglets.