Prevotella-rich enterotype may benefit gut health in finishing pigs fed diet with a high amylose-to-amylopectin ratio

摘要

To investigate the influence of baseline enterotypes and dietary starch type on the concentration of short-chain fatty acids(SCFA),numbers of butyrate producing bacteria and the expression of genes related to intestinal barrier and inflammatory response in the colon of finishing pigs,a 60-d in vivo trial was conducted.A 2-wk pre-trial with 102 crossbred(Duroc×[Landrace×Yorkshire])finishing barrows(90 d old)was conducted to screen enterotypes.Then,a total of 32 pigs(87.40±2.76 kg)with high(HPBR,>14)and low(LPBR,<2)Prevotella-to-Bacteroides ratios(PBR)in equal measure were selected and randomly divided into 4 groups with 8 replicates per group and 1 pig per replicate.The trial was designed following a 2(PBR)×2(amylose-to-amylopectin ratio,AMR)factorial arrangement.Pigs with different PBR were fed diets based on corn-soybean meal with high AMR(HAMR,1.24)or low AMR(LAMR,0.23),respectively.Results showed that neither PBR nor AMR influenced the growth performance of pigs.HPBR pigs fed HAMR diet had a higher number of colonic Clostridium cluster XIVa and higher gene expression of butyrate kinase compared to the LPBR pigs(P<0.05).The HPBR pigs fed HAMR diets also had increased colonic concentrations of total SCFA and propionate compared to the LPBR pigs(P<0.05).Comparing with other pigs,HPBR pigs fed HAMR diets showed a lower(P<0.05)expression of histone deacetylases(HDAC)gene and higher(P<0.05)expression of G protein-coupled receptor 43 gene(GPR 43)in the colonic mucosa.The interaction(P<0.05)of HPBR and HAMR was also found to decrease the gene expression of interleukin(IL)-6,IL-12,IL-1βand tumor necrosis factor-α(TNF-α)in colonic mucosa.These findings show that HAMR diet increased the abundance and activity of butyrate-producing bacteria and the concentration and absorption of SCFA,which may be associated with the decreased gene expression of inflammatory cytokines in the colonic mucosa of pigs with Prevotella-rich enterotype.All these alterations are likely to have a positive effect on the intestinal health of finishing pigs.