Effect Of Plant Extract Compound Preparation On Growth Performance,Immune Function And Intestinal Flora Of Weaned Piglets

The purpose of this experiment is to study the effects of plant extract compound preparations prepared by extracting natural plant extracts such as Astragalus,Eucommia,Honeysuckle and Bitter Wood on the growth performance,immune function and intestinal flora of weaned piglets.The appropriate addition amount of the plant extract compound preparation in the diet application of weaned piglets.A total of 225 Duroc×Landrace×Yorkshire piglets weaned at 28 days of age were randomly divided into 5 groups with5replicates each and 9 piglets per replicate.Groups ?,?,? and ? were added with 300,400,500,600 g/t plant extract compound preparations in the basic diet,and the control group was fed with Calcium oxytetracycline 250 g/t+Virginia mycin 50 g/t.The pretest period was 5 d and the trial period was 28 d.The test results show that:?1?Plant extract compound preparation can improve the growth performance of piglets and reduce the frequency of diarrhea.Compared with the control group,the feed-to-weight ratios of the test groups ?,?,?,and ? decreased by1.02%?P>0.05??7.14%?P<0.01??10.20%?P<0.01?and 2.04%?P>0.05?;diarrhea rate decreased by1.86%?P<0.01??12.14%?P<0.01??39.56%?P<0.01?and 19.62%?P<0.01?,and the test group ? had the lowest diarrhea index.?2?Plant extract compound preparation can promote the digestion and absorption of nutrients in piglets.Compared with the control group,the apparent digestibility of energy,crude protein and crude fat in the test group ? and ? was significantly increased?P<0.01?.?3?Plant extract compound preparation can improve the immune function of piglets.Compared with the control group,the spleen and thymus development index were improved in the test group ?,?,? and ?;the immunoglobulin?IgG,IgA,IgM?in the test group III was significantly higher than the control group?P<0.01?.);The levels of interleukin-2 and interleukin-4 in group ?,? and ? were significantly higher than those in the control group?P<0.05?.There was no significant difference between the experimental group ? and the experimental group ??P>0.05?,but there was an upward trend.The total protein,albumin and tumor necrosis factor-?in the experimental group ? were significantly higher than the other groups?P<0.01?;There was no significant difference in complement C₃,complement C₄ and interferon-??P>0.05?,but compared with the control group,the experimental group showed an upward trend.?4?Plant extract compound preparation has a tendency to lighten the depth of the small intestine crypt and increase the villus height.Compared with the control group,the ratio of jejunum and ileum villus height to crypt depth increased by 0.56%?P>0.05?and1.76%?P>0.05?,respectively,and the jejunum and ileum villus height of test group ? increased by 9.03%?P<0.05?and 8.82%?P<0.05?.?5?Plant extract compound preparation can increase the expression level of sodium nitrate carrier protein?SGLT1?in the small intestine of piglets.Compared with the control group,the expression of SGLT1 mRNA in the duodenum,jejunum and ileum of the test group ?,?,? and ? was significantly increased?P<0.05?.?6?Plant extract compound preparation can increase the number of beneficial bacteria in the intestinal tract of piglets and increase the diversity of intestinal microflora.Compared with the control group,the number of bifidobacteria in each test group increased?P<0.05?;the number of E.coli decreased?P>0.05?;in the number of lactobacilli,except the test group I compared with the control group The decrease was?P>0.05?,and the test group ?,? and ? were improved?P<0.05?.Compared with the control group,the abundance of jejunum and cecal bacilli in the test group ? increased by 13.74%?P<0.01?and 3.88%?P<0.05?,respectively,and the abundance of lactobacillus increased by 29.7%?P<0.01?.3.36%?P<0.05?,the abundance of actinomycetes decreased by 5.79%?P<0.05?and 0.73%?P>0.05?,respectively.In the number and diversity of jejunal species,the Ace index of test group ? was compared with test ?,?,? and control group increased by 13.07%?P<0.05?,13.93%?P<0.05?,10.22%?P<0.05?and6.54%?P<0.05?,respectively.There was no significant difference in chao1 index between the groups?P>0.05?,the Simpson index of the test group ? decreased by26.66%?P<0.05?and 35.29%?P<0.05?,respectively,and the Shannon difference was not significant between the groups?P>0.05?;In terms of quantity and diversity,the chao1index of the experimental group ? was 9.30%?P<0.05?and 6.84%?P<0.05?,respectively.The difference of Ace index between the groups was not significant?P>0.05?.There was no significant difference in Shannon and Simpson index between the groups?P>0.05?.There was no significant difference in the number of urinary and cecal OTUs between the groups?P>0.05?.Compared with the control group,the experiment was compared.The diversity of jejunal microbial diversity in group ?,? and ? was significantly different?P<0.01?.There was no significant difference in cecal microbial Beta diversity between the two groups?P>0.05?.Taken together,The above results indicate that 500 g/t plant extract compound preparation is recommended for the diet of weaned piglets.