Effects Of Niacin On Intestinal Health In Weaned Piglets

Medical researches showed that niacin has anti-inflammatory and antioxidant effects.Niacin plays an important role in repairing intestinal mucosal damage in mice and other animals.Niacin has been used as a nutritional feed additive for many years in Livestock.However,there is no research has been conducted on niacin to regulate the intestinal health of weaned piglets.Therefore,in this study,set up a comparative test of normal supply and block absorption of niacin,to investigate the effects of niacin on growth performance,diarrhea rate,intestinal barrier function and colonic microbial composition in weaned piglets.A total of 96 Duroc ×(Landrace × Yorkshire)weaned piglets(mean weight 6.65± 0.02 kg)were randomly divided into 3 groups with 8 replicates and 4 piglets per replicate.(1)Control group,feeding basic diet;(2)niacin group,feeding basic diet +niacin 20.4 mg/kg diet(total niacin 30mg/kg);(3)the niacin receptor was blocked group,feeding basic diet + Piperidinium(drugs that block GPR109 A receptors).The whole trial lasted for 14 days.The results were as follows:(1)There were no significant difference in average daily weight gain,average daily feed intake,the ratio of feed to gain and diarrhea incidence of weaned piglets in all groups(P>0.05);(2)Compared with the control group and the niacin receptor was blocked group,the niacin group significantly increased the villus heights in the jejunum of weaned piglets(P<0.01),also increased the ratio of villus height to crypt depth of jejunal(P<0.01),and significantly reduced the crypt depth of jejunal(P=0.01);Compared with the niacin receptor was blocked group,the niacin group significantly reduced the crypt depth of duodenal(P=0.05),significantly increased the ratio of villus height to crypt depth of duodenal(P<0.01),and significantly increased the villus height(P<0.01)and the ratio of villus height to crypt depth of duodenal(P<0.01);(3)the results of protein chip showed that,Compared with the control group and the niacin group,the niacin receptor was blocked group increased TGF-β in jejunal mucosa of weaned piglets(P=0.09),significantly increased IL-6,IL-12,GM-CSF and TNF-α(all P<0.05),also increased IL-4 in ileum mucosa of weaned piglets(P=0.07),the expression of TGF-β in duodenal mucosa was significantly up-regulated(P=0.01).Means inflammatory reactions in the intestine of weaned piglets;(4)Compared with the control group,the niacin receptor was blocked group increased the m RNA expression level of IL-6 in the ileum mucosa of weaned piglets(P=0.08),and significantly reduced the m RNA expression level of IL-10 in the ileum mucosa(P=0.05),significantly increased the m RNA expression level of SIRT-1 in jejunum mucosa and ileum mucosa of weaned piglets(P<0.05);(5)colonic microorganisms,Compared with the control group and the niacin group,the niacin receptor was blocked group significantly decreased the abundance of Lactobacillus(P<0.05),significantly increased the abundance of Ruminococcaceae and Turicibacter(P<0.05).Niacin can increased the abundance of Probiotics,and affects microbial structure.In conclusion,niacin can significantly improve intestinal mucosal morphology,reduce the intestinal inflammation,and increase the proportion of intestinal probiotics in weaned piglets.