Effects Of Different Concentrations Of Vitamin D In Micro-storage Soybean On Intestinal Immunity And Key Molecules Of Intestinal NF-κB Signaling Pathway In Sheep

[Objective] The purpose of this study is to study the effects of adding different concentrations of vitamin D in micro-storage bean straw on the growth performance,intestinal morphology,intestinal antioxidant activity and key molecules of NF-κB signaling pathway in the intestine of sheep.[Methods] Thirty healthy three-month-old Du Han rams(20.73±2.22 kg)were randomly divided into 6 groups,5 sheep per group.The experiment was divided into two groups.In the first group,2 groups were randomly selected,the control group was fed with dry bean straw,and the experimental group was fed with micro-storage bean straw.In the second group,5 groups were randomly selected and fed with micro-storage bean straw.The VD3 additions of sheep in the experimental group were 300,600,900 and 1200 IU/kg,respectively.The entire experiment was divided into two sections,one was the 10-day pre-feeding period and the other was the 60-day formal period.The feed intake was recorded daily,and the experimental animals were weighed every 15 days;the animals’ feed and fecal samples were collected for 3 days in the middle of the trial period for the detection of apparent digestibility;Sampling the animal’s duodenum,jejunum,ileum and colon at the end of the experiment for intestinal morphology,intestinal antioxidant function,and expression of key molecule m RNA in the intestinal NF-κB signaling pathway.[Results] The results of the first group indicated that micro-storage significantly increased the digestibility of OM,CP,NDF and ADF(P<0.05);significantly increased the villus height in duodenal(P<0.05),significantly increased the mucosal thickness in jejunum and ileum(P<0.05),significantly increased the VH/CD in each intestine(P<0.05),significantly decreased the crypt depth in each intestine(P<0.05);significantly increased the CAT activity in duodenal and jejunum(P<0.05),significantly increased the GSH-Px activity in duodenal(P<0.05),significantly decreased the MDA content in each intestine(P<0.05). The results of the second group indicated that,(1)adding 300 and 600 IU/kg VD3 significantly increased the digestibility of OM,CP and ADF(P<0.05),significantly increased the digestibility of CF(P<0.01).(2)Adding 300 and 600 IU/kg VD3 significantly increased the villus height in duodenal and jejunum(P<0.01),significantly increased the VH/CD in ileum and colon(P<0.01),significantly decreased the crypt depth in duodenal,ileum and colon(P<0.01);significantly increased the VH/CD in duodenal and jejunum(P<0.05),significantly increased the villus height in ileum and colon(P<0.05),significantly increased the mucosal thickness in colon(P<0.05).(3)Adding 300 and 600 IU/kg VD3 significantly increased the CAT activity in duodenal and ileum(P<0.01),significantly increased the GSH-Px activity in ileum and colon(P<0.01);significantly increased the T-SOD activity in duodenal,jejunum and ileum(P<0.05),significantly increased the CAT activity in jejunum and colon(P<0.05),significantly increased the GSH-Px activity in duodenal(P<0.05);significantly decreased the MDA content in duodenal,jejunum and colon(P<0.05);significantly decreased the MDA content in ileum(P<0.01).(4)Adding 300 IU/kg VD3 significantly decreased the expression of TLR4,My D88,TRAF6,IL-1β,NFKB1 and VDR m RNA(P<0.05),adding 600 IU/kg VD3 significantly decreased the expression of TLR4,My D88,TRAF6,IL-1β,NFKB1 and VDR m RNA(P<0.01).[Conclusion](1)Micro-storage significantly improved the intestinal morphology and intestinal antioxidant activity of sheep.(2)Adding 300 and 600 IU/kg VD3 significantly improved the intestinal morphology and intestinal antioxidant activity of sheep.(3)Vitamin D participated in intestinal inflammatory responses by regulating the NF-κB signaling pathway.