Background Dysregulation of lipid metabolism and its consequences on growth performance in young ruminants have attracted attention,especially in the context of alternative feeding strategies.This study aims to elucid...Background Dysregulation of lipid metabolism and its consequences on growth performance in young ruminants have attracted attention,especially in the context of alternative feeding strategies.This study aims to elucidate the effects of milk replacer(MR)feeding on growth,lipid metabolism,colonic epithelial gene expression,colonic microbiota composition and systemic metabolism in goat kids compared to breast milk(BM)feeding,addressing a critical knowledge gap in early life nutrition.Methods Ten female goat kids were divided into 2 groups:those fed breast milk(BM group)and those fed a milk replacer(MR group).Over a period of 28 d,body weight was monitored and blood and tissue samples were collected for biochemical,transcriptomic and metabolomic analyses.Profiling of the colonial microbiota was performed using 16S rRNA gene sequencing.Intestinal microbiota transplantation(IMT)experiments in gnotobiotic mice were per-formed to validate causality.Results MR-fed pups exhibited reduced daily body-weight gain due to impaired lipid metabolism as evidenced by lower serum and liver total cholesterol(TC)and non-esterified fatty acid(NEFA)concentrations.Transcriptomic analysis of the colonic epithelium revealed upregulated genes involved in negative regulation of lipid metabolism,concomitant with microbiota shifts characterized by a decrease in Firmicutes and an increase in Actinobacteria.Specifically,genera such as Bifidobacterium and Prevotella were enriched in the MR group,while Clostridium and Fae-calibacterium were depleted.Metabolomics analyses confirmed alterations in bile acid and fatty acid metabolic path-ways.IMT experiments in mice recapitulated the metabolic phenotype observed in MR-fed goats,confirming the role of the microbiota in modulating host lipid metabolism.Conclusions Milk replacer feeding in goat kids disrupts lipid metabolism and gut microbiota dynamics,result-ing in reduced growth rates and metabolic alterations.These findings highlight the importance of early nutritional intervention on metabolic programming and suggest that modulation of the gut microbiota may be a target for improving growth and metabolic health in ruminants.This study contributes to the understanding of nutritional management strategies in livestock and their impact on animal health and productivity.展开更多
Background Diarrhea is a major cause of reduced growth and mortality in piglets during the suckling and weaning periods and poses a major threat to the global pig industry.Diarrhea and gut dysbiosis may in part be pre...Background Diarrhea is a major cause of reduced growth and mortality in piglets during the suckling and weaning periods and poses a major threat to the global pig industry.Diarrhea and gut dysbiosis may in part be prevented via improved early postnatal microbial colonization of the gut.To secure better postnatal gut colonization,we hypothesized that transplantation of colonic or gastric content from healthy donors to newborn recipients would prevent diarrhea in the recipients in the post-weaning period.Our objective was to examine the impact of transplanting colonic or gastric content on health and growth parameters and paraclinical parameters in recipient single-housed piglets exposed to a weaning transition and challenged with enterotoxigenic Escherichia coli(ETEC).Methods Seventy-two 1-day-old piglets were randomized to four groups:colonic microbiota transplantation(CMT,n=18),colonic content filtrate transplantation(CcFT,n=18),gastric microbiota transplantation(GMT,n=18),or saline(CON,n=18).Inoculations were given on d 2 and 3 of life,and all piglets were milk-fed until weaning(d 20)and shortly after challenged with ETEC(d 24).We assessed growth,diarrhea prevalence,ETEC concentration,organ weight,blood parameters,small intestinal morphology and histology,gut mucosal function,and microbiota composition and diversity.Results Episodes of diarrhea were seen in all groups during both the milk-and the solid-feeding phase,possibly due to stress associated with single housing.However,CcFT showed lower diarrhea prevalence on d 27,28,and 29 compared to CON(all P<0.05).CcFT also showed a lower ETEC prevalence on d 27(P<0.05).CMT showed a higher alpha diversity and a difference in beta diversity compared to CON(P<0.05).Growth and other paraclinical endpoints were similar across groups.Conclusion In conclusion,only CcFT reduced ETEC-related post-weaning diarrhea.However,the protective effect was marginal,suggesting that higher doses,more effective modalities of administration,longer treatment periods,and better donor quality should be explored by future research to optimize the protective effects of transplantation.展开更多
Extensive evidence demonstrates that a healthy and well-balanced gut microbiota profoundly influences host nutrient absorption,immunity,and metabolism.Unlike mammals,early microbiota colonization in commercial poultry...Extensive evidence demonstrates that a healthy and well-balanced gut microbiota profoundly influences host nutrient absorption,immunity,and metabolism.Unlike mammals,early microbiota colonization in commercial poultry largely depends on the environment as chicks hatch in incubators under a relatively sterile environment(egg and incubator sterilization)without maternal-offspring interaction.The early gut microbiota remains unsaturated,providing a critical window for modulation and influencing the subsequent microbiota succession,which may have long-term health outcomes.Microbiota transplantation(MT)involves transferring the microbiota from a donor to a recipient to modulate the recipient’s microbiota toward a desired state.Successfully applied in human medicine,MT is also gaining attention in poultry production to modulate intestinal health.This review comprehensively explores factors affecting MT,its mechanisms,and its potential applications in chickens,providing insights for further research and commercial use.展开更多
Background: Pregnancy is associated with important changes in gut microbiota composition. Dietary factors may affect the diversity, composition, and metabolic activity of the intestinal microbiota. Among amino acids, ...Background: Pregnancy is associated with important changes in gut microbiota composition. Dietary factors may affect the diversity, composition, and metabolic activity of the intestinal microbiota. Among amino acids, proline is known to play important roles in protein metabolism and structure, cell differentiation, conceptus growth and development, and gut microbiota re-equilibration in case of dysbiosis.Results: Dietary supplementation with 1% proline decreased(P < 0.05) the amounts of Klebsiella pneumoniae,Peptostreptococcus productus, Pseudomonas, and Veillonella spp. in distal colonic contents than that in the control group. The colonic contents of Butyrivibrio fibrisolvens, Bifidobacterium sp., Clostridium coccoides, Clostridium coccoides-Eubacterium rectale, Clostridium leptum subgroup, Escherichia coli, Faecalibacterium prausnitzii,Fusobacterium prausnitzii, and Prevotella increased(P < 0.05) on d 70 of pregnancy as compared with those on d 45 of pregnancy. The colonic concentrations of acetate, total straight-chain fatty acid, and total short-chain fatty acids(SCFA) in the proline-supplemented group were lower(P < 0.05), and butyrate level(P = 0.06) decreased as compared with the control group. Almost all of the SCFA displayed higher(P < 0.05) concentrations in proximal colonic contents on d 70 of pregnancy than those on d 45 of pregnancy. The concentrations of 1,7-heptyl diamine(P = 0.09) and phenylethylamine(P < 0.05) in proximal colonic contents were higher, while those of spermidine(P = 0.05) and total bioamine(P = 0.06) tended to be lower in the proline-supplemented group than those in the control group. The concentrations of spermidine, spermine, and total bioamine in colonic contents were higher(P < 0.05) on d 70 of pregnancy than those measured on d 45 of pregnancy. In contrast, the concentration of phenylethylamine was lower(P < 0.05) on d 70 than on d 45 of pregnancy.(Continued on next page)(Continued from previous page)Conclusion: These findings indicate that L-proline supplementation modifies both the colonic microbiota composition and the luminal concentrations of several bacterial metabolites. Furthermore, our data show that both the microbiota composition and the concentrations of bacterial metabolites are evolving in the course of pregnancy. These results are discussed in terms of possible implication in terms of luminal environment and consequences for gut physiology and health.展开更多
Background:High-protein diets can increase the colonic health risks.A moderate reduction of dietary crude-protein(CP)level can improve the colonic bacterial community and mucosal immunity of pigs.However,greatly reduc...Background:High-protein diets can increase the colonic health risks.A moderate reduction of dietary crude-protein(CP)level can improve the colonic bacterial community and mucosal immunity of pigs.However,greatly reducing the dietary CP level,even supplemented with all amino acids(AAs),detrimentally affects the colonic health,which may be due to the lack of protein-derived peptides.Therefore,this study evaluated the effects of supplementation of casein hydrolysate(peptide source)in low-protein(LP)diets,in comparison with AAs supplementation,on the colonic microbiota,microbial metabolites and mucosal immunity in pigs,aiming to determine whether a supplementation of casein hydrolysate can improve colonic health under very LP level.Twenty-one pigs(initial BW 19.90±1.00 kg,63±1 days of age)were assigned to three groups and fed with control diet(16%CP),LP diets(13%CP)supplemented with free AAs(LPA)or casein hydrolysate(LPC)for 4 weeks.Results:Compared with control diet,LPA and LPC diet decreased the relative abundance of Streptococcus and Escherichia coli,and LPC diet further decreased the relative abundance of Proteobacteria.LPC diet also increased the relative abundance of Lactobacillus reuteri.Both LP diets decreased concentrations of ammonia and cadaverine,and LPC diet also reduced concentrations of putrescine,phenol and indole.Moreover,LPC diet increased total short-chain fatty acid concentration.In comparison with control diet,both LP diets decreased protein expressions of Toll-like receptor-4,nuclear factor-κB,interleukin-1βand tumor necrosis factor-α,and LPC diet further decreased protein expressions of nucleotide-binding oligomerization domain protein-1 and interferon-γ.LPC diet also increased protein expressions of G-protein coupled receptor-43,interleukin-4,transforming growth factor-β,immunoglobulin A and mucin-4,which are indicators for mucosal defense activity.Conclusions:The results showed that supplementing casein hydrolysate showed beneficial effects on the colonic microbiota and mucosal immunity and barrier function in comparison with supplementing free AAs in LP diets.These findings may provide new framework for future nutritional interventions for colon health in pigs.展开更多
Many epidemiological and experimental studies have suggested that dietary fiber plays an important role in colon cancer prevention. These findings may relate to the ability of fiber to reduce the contact time of carci...Many epidemiological and experimental studies have suggested that dietary fiber plays an important role in colon cancer prevention. These findings may relate to the ability of fiber to reduce the contact time of carcinogens within the intestinal lumen and to promote healthy gut microbiota, which modifies the host's metabolism in various ways. Elucidation of the mechanisms by which dietary fiber-dependent changes in gut microbiota enhance bile acid deconjugation, produce short chain fatty acids, and modulate inflammatory bioactive substances can lead to a better understanding of the beneficial role of dietary fiber. This article reviews the current knowledge concerning the mechanisms via which dietary fiber protects against colon cancer.展开更多
Resistant starch type 3 (RS3) produced from high amylose food sources through retrogradation or enzymatic process is known to have physiological function as dietary fiber. Fermentation of RS3 by colonic microorganisms...Resistant starch type 3 (RS3) produced from high amylose food sources through retrogradation or enzymatic process is known to have physiological function as dietary fiber. Fermentation of RS3 by colonic microorganisms produced SCFA (acetate, propionate, and butyrate), maintained the health of colon, balance of gut microbiota, preventing inflammatory bowel diseases (IBD) and colon cancer. RS3 in this study was produced from IR-42 and Inpari-16 broken rice by enzymatic treatment (combination of amylase-pullulanase). The Resistant Starch was fermented for 12 and 24 h by colonic microbiota (extracted from healthy human subject), Clostiridium butyricum BCC-B2571, or Eubacterium rectale DSM 17629. SCFA produced was analyzed by gas chromatography. Treatment by amylase-pullulanase combination was advantageous to increase their RS3 content. The result showed that after enzymatic process, the RS3 content of IR-42 (41.13%) was not significantly different (p 0.05) from that of Inpari-16 (37.70%). High concentration of acetate (82.5 mM) and propionate (7.5 mM) were produced by colonic microbiota after 12 h fermentation and best concentration of butyrate (6.8 mM) was produced by colonic microbiota after 24 h fermentation. It is clear that utilization of colonic microbiota rather than single strain was better in the production of SCFA.展开更多
Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. i...Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred(Duroc × Landrace × Large White) female pigs(initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet(Control group) and two diets corresponding to 4%(H1 group) and 8%(H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens(replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment(n =8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.Results: The results showed that the H1 diet significantly increased the abundance of Lactobacillus,Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group(P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group(P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group(P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group(P < 0.05);the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower(P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group(P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole(P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines(IFN-γ) compared with pigs in the control group(P < 0.05), and up-regulated anti-inflammatory cytokine(IL-10) and intestinal barrier genes(ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group(P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.Conclusions: Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.展开更多
基金financially supported by National Natural Science Foundation of China (32160801)China Agriculture Research System (CARS-39-12)+1 种基金Young Talent Fund of Association for Science and Technology in Shaanxi, China (2023-6-2-1)“Double-chain” project on livestock breeding (2022GDTSLD-46)
文摘Background Dysregulation of lipid metabolism and its consequences on growth performance in young ruminants have attracted attention,especially in the context of alternative feeding strategies.This study aims to elucidate the effects of milk replacer(MR)feeding on growth,lipid metabolism,colonic epithelial gene expression,colonic microbiota composition and systemic metabolism in goat kids compared to breast milk(BM)feeding,addressing a critical knowledge gap in early life nutrition.Methods Ten female goat kids were divided into 2 groups:those fed breast milk(BM group)and those fed a milk replacer(MR group).Over a period of 28 d,body weight was monitored and blood and tissue samples were collected for biochemical,transcriptomic and metabolomic analyses.Profiling of the colonial microbiota was performed using 16S rRNA gene sequencing.Intestinal microbiota transplantation(IMT)experiments in gnotobiotic mice were per-formed to validate causality.Results MR-fed pups exhibited reduced daily body-weight gain due to impaired lipid metabolism as evidenced by lower serum and liver total cholesterol(TC)and non-esterified fatty acid(NEFA)concentrations.Transcriptomic analysis of the colonic epithelium revealed upregulated genes involved in negative regulation of lipid metabolism,concomitant with microbiota shifts characterized by a decrease in Firmicutes and an increase in Actinobacteria.Specifically,genera such as Bifidobacterium and Prevotella were enriched in the MR group,while Clostridium and Fae-calibacterium were depleted.Metabolomics analyses confirmed alterations in bile acid and fatty acid metabolic path-ways.IMT experiments in mice recapitulated the metabolic phenotype observed in MR-fed goats,confirming the role of the microbiota in modulating host lipid metabolism.Conclusions Milk replacer feeding in goat kids disrupts lipid metabolism and gut microbiota dynamics,result-ing in reduced growth rates and metabolic alterations.These findings highlight the importance of early nutritional intervention on metabolic programming and suggest that modulation of the gut microbiota may be a target for improving growth and metabolic health in ruminants.This study contributes to the understanding of nutritional management strategies in livestock and their impact on animal health and productivity.
基金support by European Union's Horizon 2020 Research and Innovation Program under Grant Agreement No.862829,project AVANT-Alternatives to Veterinary ANTimicrobials.
文摘Background Diarrhea is a major cause of reduced growth and mortality in piglets during the suckling and weaning periods and poses a major threat to the global pig industry.Diarrhea and gut dysbiosis may in part be prevented via improved early postnatal microbial colonization of the gut.To secure better postnatal gut colonization,we hypothesized that transplantation of colonic or gastric content from healthy donors to newborn recipients would prevent diarrhea in the recipients in the post-weaning period.Our objective was to examine the impact of transplanting colonic or gastric content on health and growth parameters and paraclinical parameters in recipient single-housed piglets exposed to a weaning transition and challenged with enterotoxigenic Escherichia coli(ETEC).Methods Seventy-two 1-day-old piglets were randomized to four groups:colonic microbiota transplantation(CMT,n=18),colonic content filtrate transplantation(CcFT,n=18),gastric microbiota transplantation(GMT,n=18),or saline(CON,n=18).Inoculations were given on d 2 and 3 of life,and all piglets were milk-fed until weaning(d 20)and shortly after challenged with ETEC(d 24).We assessed growth,diarrhea prevalence,ETEC concentration,organ weight,blood parameters,small intestinal morphology and histology,gut mucosal function,and microbiota composition and diversity.Results Episodes of diarrhea were seen in all groups during both the milk-and the solid-feeding phase,possibly due to stress associated with single housing.However,CcFT showed lower diarrhea prevalence on d 27,28,and 29 compared to CON(all P<0.05).CcFT also showed a lower ETEC prevalence on d 27(P<0.05).CMT showed a higher alpha diversity and a difference in beta diversity compared to CON(P<0.05).Growth and other paraclinical endpoints were similar across groups.Conclusion In conclusion,only CcFT reduced ETEC-related post-weaning diarrhea.However,the protective effect was marginal,suggesting that higher doses,more effective modalities of administration,longer treatment periods,and better donor quality should be explored by future research to optimize the protective effects of transplantation.
基金Haoran Zhao would like to acknowledge the support provided by China Scholarship Council(CSC)of the Ministry of Education,P.R.China(CSC No.202206850006)supported by funding from VLAIO with project number(HBC.2023.0172),HEPPY Markers-Establishment of biomarkers of Health and Eubiosis in Pigs and Poultry.
文摘Extensive evidence demonstrates that a healthy and well-balanced gut microbiota profoundly influences host nutrient absorption,immunity,and metabolism.Unlike mammals,early microbiota colonization in commercial poultry largely depends on the environment as chicks hatch in incubators under a relatively sterile environment(egg and incubator sterilization)without maternal-offspring interaction.The early gut microbiota remains unsaturated,providing a critical window for modulation and influencing the subsequent microbiota succession,which may have long-term health outcomes.Microbiota transplantation(MT)involves transferring the microbiota from a donor to a recipient to modulate the recipient’s microbiota toward a desired state.Successfully applied in human medicine,MT is also gaining attention in poultry production to modulate intestinal health.This review comprehensively explores factors affecting MT,its mechanisms,and its potential applications in chickens,providing insights for further research and commercial use.
基金jointly supported by grants from the National Nature Science Foundation of China(31572421 and 31270044)National Key R&D Program(2017YFD0500503)“Western Light”key program for Talent Cultivation from Chinese Academy of Sciences,and Chinese Academy of Sciences Visiting Professorship for Senior International Scientists(F.Blachier,2013T2S0014)
文摘Background: Pregnancy is associated with important changes in gut microbiota composition. Dietary factors may affect the diversity, composition, and metabolic activity of the intestinal microbiota. Among amino acids, proline is known to play important roles in protein metabolism and structure, cell differentiation, conceptus growth and development, and gut microbiota re-equilibration in case of dysbiosis.Results: Dietary supplementation with 1% proline decreased(P < 0.05) the amounts of Klebsiella pneumoniae,Peptostreptococcus productus, Pseudomonas, and Veillonella spp. in distal colonic contents than that in the control group. The colonic contents of Butyrivibrio fibrisolvens, Bifidobacterium sp., Clostridium coccoides, Clostridium coccoides-Eubacterium rectale, Clostridium leptum subgroup, Escherichia coli, Faecalibacterium prausnitzii,Fusobacterium prausnitzii, and Prevotella increased(P < 0.05) on d 70 of pregnancy as compared with those on d 45 of pregnancy. The colonic concentrations of acetate, total straight-chain fatty acid, and total short-chain fatty acids(SCFA) in the proline-supplemented group were lower(P < 0.05), and butyrate level(P = 0.06) decreased as compared with the control group. Almost all of the SCFA displayed higher(P < 0.05) concentrations in proximal colonic contents on d 70 of pregnancy than those on d 45 of pregnancy. The concentrations of 1,7-heptyl diamine(P = 0.09) and phenylethylamine(P < 0.05) in proximal colonic contents were higher, while those of spermidine(P = 0.05) and total bioamine(P = 0.06) tended to be lower in the proline-supplemented group than those in the control group. The concentrations of spermidine, spermine, and total bioamine in colonic contents were higher(P < 0.05) on d 70 of pregnancy than those measured on d 45 of pregnancy. In contrast, the concentration of phenylethylamine was lower(P < 0.05) on d 70 than on d 45 of pregnancy.(Continued on next page)(Continued from previous page)Conclusion: These findings indicate that L-proline supplementation modifies both the colonic microbiota composition and the luminal concentrations of several bacterial metabolites. Furthermore, our data show that both the microbiota composition and the concentrations of bacterial metabolites are evolving in the course of pregnancy. These results are discussed in terms of possible implication in terms of luminal environment and consequences for gut physiology and health.
基金supported by National Key Basic Research Program of China(2013CB127300)Natural Science Foundation of China(31430082).
文摘Background:High-protein diets can increase the colonic health risks.A moderate reduction of dietary crude-protein(CP)level can improve the colonic bacterial community and mucosal immunity of pigs.However,greatly reducing the dietary CP level,even supplemented with all amino acids(AAs),detrimentally affects the colonic health,which may be due to the lack of protein-derived peptides.Therefore,this study evaluated the effects of supplementation of casein hydrolysate(peptide source)in low-protein(LP)diets,in comparison with AAs supplementation,on the colonic microbiota,microbial metabolites and mucosal immunity in pigs,aiming to determine whether a supplementation of casein hydrolysate can improve colonic health under very LP level.Twenty-one pigs(initial BW 19.90±1.00 kg,63±1 days of age)were assigned to three groups and fed with control diet(16%CP),LP diets(13%CP)supplemented with free AAs(LPA)or casein hydrolysate(LPC)for 4 weeks.Results:Compared with control diet,LPA and LPC diet decreased the relative abundance of Streptococcus and Escherichia coli,and LPC diet further decreased the relative abundance of Proteobacteria.LPC diet also increased the relative abundance of Lactobacillus reuteri.Both LP diets decreased concentrations of ammonia and cadaverine,and LPC diet also reduced concentrations of putrescine,phenol and indole.Moreover,LPC diet increased total short-chain fatty acid concentration.In comparison with control diet,both LP diets decreased protein expressions of Toll-like receptor-4,nuclear factor-κB,interleukin-1βand tumor necrosis factor-α,and LPC diet further decreased protein expressions of nucleotide-binding oligomerization domain protein-1 and interferon-γ.LPC diet also increased protein expressions of G-protein coupled receptor-43,interleukin-4,transforming growth factor-β,immunoglobulin A and mucin-4,which are indicators for mucosal defense activity.Conclusions:The results showed that supplementing casein hydrolysate showed beneficial effects on the colonic microbiota and mucosal immunity and barrier function in comparison with supplementing free AAs in LP diets.These findings may provide new framework for future nutritional interventions for colon health in pigs.
基金Supported by The United States Department of Agriculture
文摘Many epidemiological and experimental studies have suggested that dietary fiber plays an important role in colon cancer prevention. These findings may relate to the ability of fiber to reduce the contact time of carcinogens within the intestinal lumen and to promote healthy gut microbiota, which modifies the host's metabolism in various ways. Elucidation of the mechanisms by which dietary fiber-dependent changes in gut microbiota enhance bile acid deconjugation, produce short chain fatty acids, and modulate inflammatory bioactive substances can lead to a better understanding of the beneficial role of dietary fiber. This article reviews the current knowledge concerning the mechanisms via which dietary fiber protects against colon cancer.
文摘Resistant starch type 3 (RS3) produced from high amylose food sources through retrogradation or enzymatic process is known to have physiological function as dietary fiber. Fermentation of RS3 by colonic microorganisms produced SCFA (acetate, propionate, and butyrate), maintained the health of colon, balance of gut microbiota, preventing inflammatory bowel diseases (IBD) and colon cancer. RS3 in this study was produced from IR-42 and Inpari-16 broken rice by enzymatic treatment (combination of amylase-pullulanase). The Resistant Starch was fermented for 12 and 24 h by colonic microbiota (extracted from healthy human subject), Clostiridium butyricum BCC-B2571, or Eubacterium rectale DSM 17629. SCFA produced was analyzed by gas chromatography. Treatment by amylase-pullulanase combination was advantageous to increase their RS3 content. The result showed that after enzymatic process, the RS3 content of IR-42 (41.13%) was not significantly different (p 0.05) from that of Inpari-16 (37.70%). High concentration of acetate (82.5 mM) and propionate (7.5 mM) were produced by colonic microbiota after 12 h fermentation and best concentration of butyrate (6.8 mM) was produced by colonic microbiota after 24 h fermentation. It is clear that utilization of colonic microbiota rather than single strain was better in the production of SCFA.
基金supported by the Presidential Foundation of the Guangdong Academy of Agricultural Sciences(201802B,201621)Guangdong Modern Agro-industry Technology Research System(2016LM1080,2017LM1080)
文摘Background: Insects, such as Hermetia illucens larvae, are rich in chitin and proteins, and represent a suitable feed ingredient replacement for animals. However, little is known about the effect of administering H. illucens larvae on intestinal microbiota, bacterial metabolite profiles, and mucosal immune status in animals. This study aimed to investigate the effects of administering H. illucens larvae on colonic microbiota and bacterial metabolites production in finishing pigs. Seventy-two crossbred(Duroc × Landrace × Large White) female pigs(initial body weight, 76.0 ± 0.52 kg) were randomly allocated to three different dietary treatments: a control diet(Control group) and two diets corresponding to 4%(H1 group) and 8%(H2 group) H. illucens larvae inclusion levels, respectively. Each treatment consisted of eight pens(replicates), with three pigs per pen. After 46 days of feeding, eight pigs per treatment(n =8) were slaughtered, and the colonic digesta and mucosa were collected for microbial composition and microbial fermentation products, and genes expression analyses.Results: The results showed that the H1 diet significantly increased the abundance of Lactobacillus,Pseudobutyrivibrio, Roseburia, and Faecalibacterium compared with those in the control group(P < 0.05), with a decrease in the abundance of Streptococcus. The numbers of Lactobacillus, Roseburia, and Clostridium cluster XIVa were significantly greater in the H1 group than in the control group(P < 0.05). Meanwhile, H2 diet increased the number of Clostridium cluster XIVa compared with the control group(P < 0.05). For colonic metabolites, total short chain fatty acids, butyrate, and isobutyrate concentrations were significantly higher in the H1 group than those in the control group(P < 0.05);the H1 treatment caused a striking decrease in protein fermentation compared with the control group, as the concentrations of total amines, cadaverine, tryptamine, phenol, p-cresol, and skatole were significantly lower(P < 0.05). Additionally, H2 diet also increased butyrate concentration compared with control group(P < 0.05), while decreased the concentrations of phenol, p-cresol, and skatole(P < 0.05). Pigs in the H1 group down-regulated the expression of TLR-4 and pro-inflammatory cytokines(IFN-γ) compared with pigs in the control group(P < 0.05), and up-regulated anti-inflammatory cytokine(IL-10) and intestinal barrier genes(ZO-1, occludin, and mucin-1). H2 diet up-regulated the expression of ZO-1 compared with control group(P < 0.05). Furthermore, the changes in the colonic mucosal gene expression were associated with changes in the bacterial composition and their metabolites.Conclusions: Collectively, dietary inclusion of Hermetia illucens larvae may enhance mucosal immune homeostasis of pigs via altering bacterial composition and their metabolites. These findings provide a new perspective on insect meal as a sustainable protein source rich in nutrient ingredients for swine.