Effect Of Pig Intestinal Microorganism On Nutrient Digestion And Immune Function Based On Fecal Microbial Transplantation Technology

Intestinal microbiota as a new research hotspot in recent years,its function and potential application value are gradually paid more attention by more and more researchers.Fecal microbial transplantation as a research tool in intestinal microbial research can help researchers explore the physiological functions of gut microbiota.Based on this,the following two experiments were designed to explore the effects of microbial transplantation of Meishan gilts on the digestibility and immune function of Landrace-Large white gilts.Experiment Ⅰ: The effects of fecal microbial transplantation of Meishan gilts on the apparent nutrient digestibility,serum immune index and intestinal barrier function of Landrace-Large white gilts.Twenty-eight Landrace-Large white gilts with similar body weight and age were randomly divided into 4 groups,with 7 replicates in each group and 1 eplicate in each group.These 4 groups were control groups(Ctrl),sterilization groups(S-FMT),low concentration groups(L-FMT)and high concentration groups(H-FMT),respectively.The fecal broth donor pigs were from eight Meishan gilts with similar body sizes and ages.The trial period lasted for 180 days.The results were shown as below:1)there was no significant difference in the digestibility of crude protein and crude fiber between different treatment groups(P > 0.05).For crude fat,the digestibility of L-FMT was significant lower than that of the other three groups(P < 0.05),and there was no significant difference among the other three groups(P > 0.05).2)The absolute value of lymphocyte in plasma of sterilized group was significantly higher than that of H-FMT(P < 0.05),however,there were no significant differences among the other three groups(P > 0.05).The concentration of erythrocyte in plasma of control group was significantly higher than that of sterilized group(P < 0.05),however,there were no significant differences among the other three groups(P > 0.05).The difference of other blood routine indexes was not significant(P > 0.05),and the blood routine indexes were in normal physiological range,indicating that the experimental pigs were in a relatively healthy state.3)The TNF-α concentration of serum in the Ctrl was significantly higher than that in other three groups(P < 0.05),however,there were no significant differences among the other three groups(P > 0.05).The IL-10 concentration of serum in the Ctrl was significantly higher than that in other three groups(P < 0.05),however,there were no significant differences among other three groups(P > 0.05).The rank of IL-1β concentration in serum was: Ctrl > H-FMT > L-FMT > S-FMT(P < 0.05).There was no significant difference between the L-FMT and the S-FMT(P > 0.05);and there was no significant difference in IL-6 and IGF-I levels of serum between different treatment groups(P > 0.05).4)The concentration of IgA in the Ctrl was significantly higher than that in the H-FMT(P < 0.05).There was no significant difference in IgG concentration between different treatment groups(P > 0.05).There was no significant difference in IgM concentration between different treatment groups(P > 0.05).5)The rank of villus height of the duodenum was: H-FMT > L-FMT > Ctrl > S-FMT(P < 0.05),however,there was no significant difference in crypt depth(P < 0.05).The rank of villus height/crypt depth was: H-FMT > Ctrl(P < 0.05),L-FMT > S-FMT(P < 0.05),the difference between the Ctrl and the L-FMT and the S-FMT were not significant(P > 0.05).The rank of villus height of jejunum was: Ctrl > S-FMT > L-FMT and H-FMT(P < 0.05).There was no significant difference between L-FMT and H-FMT in term of villus height of jejunum(P>0.05).The rank of crypt depth was: Ctrl > S-FMT > L-FMT and H-FMT(P < 0.05).There were no significant differences between the L-FMT and the H-FMT in term of crypt depth(P > 0.05).The rank of villus height/crypt depth was: L-FMT > S-FMT(P < 0.05),and there was no significant difference between the Ctrl and the H-FMT(P > 0.05).The rank of villus height of the ileum was: L-FMT > Ctrl and S-FMT(P < 0.05),and H-FMT > S-FMT(P < 0.05).There was no significant difference between L-FMT and H-FMT in term of villus height(P > 0.05).The rank of crypt depth was: H-FMT > S-FMT(P < 0.05).There was no significant difference between the other treatment groups in term of crypt depth(P > 0.05),and the villus height/crypt depth in L-FMT was significantly higher than that in Ctrl and S-FMT(P < 0.05),and there was no significant difference between the Ctrl and the S-FMT(P > 0.05).Experiment Ⅱ: The effects of fecal microbial transplantation of Meishan gilts on the intestinal microbial composition and liver metabolome of Landrace-Large white binary gilts were investigated.The results were shown as below:1)The clustering of the donor Meishan gilts group and the L-FMT was better,and the bacterial composition of the L-FMT had a tendency to change the donor Meishan gilts.2)At the classification level of the phylun,the main identified bacteria were Firmicutes,Bacteroidetes,Proteobacteria,Actinobacteria and Spirochaetes.3)The relative abundance of Bacteroides in the Ctrl was significantly lower than that in the L-FMT(P < 0.05).The relative abundance of Firmicutes in the Ctrl was significantly higher than that in the L-FMT(P < 0.05).The relative abundance ratio of Firmicutes and Bacteroidetes(F/B)in the Ctrl was significantly higher than that in the L-FMT(P < 0.05).4)The identified differential metabolites were annotated on the metabolic pathway through KEGG database.Compared with the Ctrl,L-FMT enriched more metabolic pathways,including amino acid metabolic pathways,metabolic pathways of unsaturated fatty acid synthesis,and linoleic acid metabolic pathways.