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Frontiers in Cellular and Infection... 2024Post-weaning diarrhoea (PWD) is a multifactorial disease that affects piglets after weaning, contributing to productive and economic losses. Its control includes the use... (Review)
Review
INTRODUCTION
Post-weaning diarrhoea (PWD) is a multifactorial disease that affects piglets after weaning, contributing to productive and economic losses. Its control includes the use of in-feed prophylactic antibiotics and therapeutic zinc oxide (ZnO), treatments that, since 2022, are no longer permitted in the European Union due to spread of antimicrobial resistance genes and pollution of soil with heavy metals. A dysbiosis in the microbiota has been suggested as a potential risk factor of PWD onset. Understanding pig's microbiota development around weaning and its changes in response to ZnO and antibiotics is crucial to develop feasible alternatives to prophylactic and metaphylactic antimicrobial use.
METHODS
This study used shotgun metagenomic sequencing to investigate the environmental and faecal microbiota on 10 farms using (Treated) or not using (ZnO-free) in-feed antibiotics and ZnO during the first 14 days post-weaning (dpw). Environmental samples from clean pens were collected at weaning day (0dpw), and faecal samples at 0, 7 and 14dpw. Diarrhoeic faecal samples were collected at 7dpw when available.
RESULTS
The analysis of data revealed that the faecal microbiota composition and its functionality was impacted by the sampling time point (microbiota maturation after weaning) but not by the farm environment. Treatment with antibiotics and ZnO showed no effects on diversity indices while the analyses of microbiota taxonomic and functional profiles revealed increased abundance of taxa and metabolic functions associated with or different species of . on the Treated farms, and with and on the ZnO-free farms. The analysis of diarrhoea samples revealed that the treatment favoured the microbiota transition or maturation from 0dpw to 14dpw in Treated farms, resembling the composition of healthy animals, when compared to diarrhoea from ZnO-free farms, which were linked in composition to 0dpw samples.
DISCUSSION
The results provide a comprehensive overview of the beneficial effects of ZnO and antibiotics in PWD in the microbiota transition after weaning, preventing the overgrowth of pathogens such as pathogenic and revealing the key aspects in microbiota maturation that antibiotics or ZnO alternatives should fulfil.
Topics: Swine; Animals; Escherichia coli; Anti-Bacterial Agents; Zinc Oxide; Diarrhea; Microbiota
PubMed: 38384302
DOI: 10.3389/fcimb.2024.1354449 -
Frontiers in Microbiology 2024This study aimed to investigate the digestive function, urea utilization ability, and bacterial composition changes in rumen microbiota under high urea (5% urea in diet)...
INTRODUCTION
This study aimed to investigate the digestive function, urea utilization ability, and bacterial composition changes in rumen microbiota under high urea (5% urea in diet) over 23 days of continuous batch culture .
METHODS
The gas production, dry matter digestibility, and bacterial counts were determined for the continuously batch-cultured rumen fluid (CRF). The changes in fermentation parameters, NH-N utilization efficiency, and microbial taxa were analyzed in CRF and were compared with that of fresh rumen fluid (RF), frozen rumen fluid (FRF, frozen rumen fluid at -80°C for 1 month), and the mixed rumen fluid (MRF, 3/4 RF mixed with 1/4 CRF) with rumen fermentation.
RESULTS
The results showed that the dry matter digestibility remained stable while both the microbial counts and diversity significantly decreased over the 23 days of continuous batch culture. However, the NH-N utilization efficiency of the CRF group was significantly higher than that of RF, FRF, and MRF groups ( < 0.05), while five core genera including , , , , and were retained after 23 days of continuous batch culture. The NH-N utilization efficiency was effectively improved after continuous batch culture , and , , , , , , and were identified to explain 75.72% of the variation in NH-N utilization efficiency with the RandomForest model.
CONCLUSION
Thus, core bacterial composition and function retained under high urea (5% urea in diet) over 23 days of continuous batch culture and bacterial biomarkers for ammonia utilization were illustrated in this study. These findings might provide potential applications in improving the efficiency and safety of non-protein nitrogen utilization in ruminants.
PubMed: 38328430
DOI: 10.3389/fmicb.2024.1331977 -
Microorganisms Jan 2024The Gram-negative, strictly anaerobic bacterium was first isolated from the rumen in 1953 and is common in the mammalian gastrointestinal tract. Its ability to use... (Review)
Review
The Gram-negative, strictly anaerobic bacterium was first isolated from the rumen in 1953 and is common in the mammalian gastrointestinal tract. Its ability to use either lactate or glucose as its major energy sources for growth has been well documented, although it can also ferment amino acids into ammonia and branched-chain fatty acids, which are growth factors for other bacteria. The ruminal abundance of usually increases in animals fed grain-based diets due to its ability to use lactate (the product of rapid ruminal sugar fermentation), especially at a low ruminal pH (<5.5). has been proposed as a potential dietary probiotic to prevent ruminal acidosis in feedlot cattle and high-producing dairy cows. However, this bacterium has also been associated with milk fat depression (MFD) in dairy cows, although proving a causative role has remained elusive. This review summarizes the unique physiology of this intriguing bacterium and its functional role in the ruminal community as well as its role in the health and productivity of the host animal. In addition to its effects in the rumen, the ability of to produce C-C carboxylic acids-potential precursors for industrial fuel and chemical production-is examined.
PubMed: 38276203
DOI: 10.3390/microorganisms12010219 -
Journal of Gastroenterology Apr 2024Alterations in gut microbiota are associated with the pathogenesis of metabolic diseases, including metabolic-associated fatty liver disease (MAFLD). The aim of this...
BACKGROUND/AIM
Alterations in gut microbiota are associated with the pathogenesis of metabolic diseases, including metabolic-associated fatty liver disease (MAFLD). The aim of this study was to evaluate gut microbiota composition and functionality in patients with morbid obesity with different degrees of MAFLD, as assessed by biopsy.
SUBJECTS/METHODS
110 patients with morbid obesity were evaluated by biopsy obtained during bariatric surgery for MAFLD. Stool samples were collected prior to surgery for microbiota analysis.
RESULTS
Gut microbiota from patients with steatosis and non-alcoholic steatohepatitis (NASH) were characterized by an enrichment in Enterobacteriaceae (an ethanol-producing bacteria), Acidaminococcus and Megasphaera and the depletion of Eggerthellaceae and Ruminococcaceae (SCFA-producing bacteria). MAFLD was also associated with enrichment of pathways related to proteinogenic amino acid degradation, succinate production, menaquinol-7 (K2-vitamin) biosynthesis, and saccharolytic and proteolytic fermentation. Basic histological hepatic alterations (steatosis, necroinflammatory activity, or fibrosis) were associated with specific changes in microbiota patterns. Overall, the core microbiome related to basic histological alterations in MAFLD showed an increase in Enterobacteriaceae and a decrease in Ruminococcaceae. Specifically, Escherichia coli was associated with steatosis and necroinflammatory activity, whilst Escherichia-shigella was associated with fibrosis and necroinflammatory activity.
CONCLUSIONS
We established a link between gut microbiota alterations and histological injury in liver diagnosis using biopsy. Harmful products such as ethanol or succinate may be involved in the pathogenesis and progression of MAFLD. Thus, these alterations in gut microbiota patterns and their possible metabolic pathways could add information to the classical predictors of MAFLD severity and suggest novel metabolic targets.
Topics: Humans; Non-alcoholic Fatty Liver Disease; Gastrointestinal Microbiome; Obesity, Morbid; Ethanol; Fibrosis; Succinates
PubMed: 38265508
DOI: 10.1007/s00535-023-02075-7 -
MSystems Feb 2024Ruminal microbiota is gradually established after birth, while microbiota maturation could be highly diverse because of varied solid dietary accessibility. However, how...
Ruminal microbiota is gradually established after birth, while microbiota maturation could be highly diverse because of varied solid dietary accessibility. However, how the ruminal microbiota accreted from postnatal hay diets alters rumen epithelial development, and how this affects animal health remains largely unknown. Here, neonatal lambs were introduced to starchy corn-soybean starter or corn-soybean starter + alfalfa hay (AH) to investigate the influences of early life ruminal microbiome on rumen epithelial development using integrated 16s rRNA sequencing-metagenome-transcriptome approaches. The results showed that AH introduction elevated average daily weight gain, rumen weight and volume, rumen epithelial papillae length, and rumen muscle layer thickness. Meanwhile, the relative abundance of fibrolytic bacteria ( R-7 group, UCG-001, and ), acetate producer ( and and propionate producer was increased in the rumen content by AH supplementation ( < 0.05). Moreover, AH introduction decreased the relative abundance of total CAZymes, CBM, and GH and increased the abundance of KO genes related to volatile fatty acid (VFA) generation in the rumen content. AH lambs had a higher relative abundance of , , and ( < 0.05), while a lower relative abundance of , , , , , and ( < 0.05) in the rumen epithelial samples. Furthermore, these alterations in ruminal microbial structure and function resulted in ruminal epithelial cell proliferation and development pathways activation. In summary, AH introduction benefited ruminal fiber degradation and VFA generation bacteria colonization and promoted ruminal epithelial development. These findings provide new insights into ruminal microbial-host interactions in the early life.IMPORTANCEWhile it is established that a fiber-rich diet promotes rumen development in lambs, further research is needed to investigate the precise response of rumen microbiota and epithelium to high-quality alfalfa hay. Here, we observed that the inclusion of alfalfa hay led to a discernible alteration in the developmental trajectory of the rumen. Notably, there was a favorable shift in the rumen's volume, morphology, and the development of rumen papillae. Furthermore, ruminal microbial structure and function resulted in ruminal epithelial cell proliferation and development pathways activation, collectively provide compelling evidence supporting the capacity of alfalfa hay to enhance rumen development and health through ruminal micrbiota-host crosstalks. Our findings elucidate the functional response of the rumen to alfalfa hay introduction, providing new insights into strategies for promoting healthy development of the rumen in young ruminants.
Topics: Sheep; Animals; Medicago sativa; RNA, Ribosomal, 16S; Rumen; Animal Feed; Fatty Acids, Volatile; Sheep, Domestic; Ruminants; Microbiota; Weight Gain
PubMed: 38179946
DOI: 10.1128/msystems.01034-23 -
Food Chemistry: X Mar 2024Tea ( L.) flower polysaccharides (TFPS) have various health-promoting functions. In the present work, the structure of a purified TFPS fraction, namely TFPS-1-3p, and...
Tea ( L.) flower polysaccharides (TFPS) have various health-promoting functions. In the present work, the structure of a purified TFPS fraction, namely TFPS-1-3p, and its digestive properties were investigated. The results demonstrated that TFPS-1-3p was a typical heteropolysaccharide consisting of rhamnose (Rha), arabinose (Ara), galactose (Gal) and galacturonic acid (GalA) with a molecular weight of 47.77 kDa. The backbone of TFPS-1-3p contained → 4)-α-d-GalA(-6-OMe)-(1 → 4)-α-GalA-(1 → and → 4)-α-d-GalA(-6-OMe)-(1 → 2,4)-α-l-Rha-(1 → linkages. The branch linkages in TFPS-1-3p contained → 6)-β-d-Gal-(1→, →3,6)-β-d-Gal-(1→, →5)-α-l-Ara-(1 → and → 3,5)-α-l-Ara-(1 →. Subsequently, TFPS-1-3p could not be degraded under simulated human gastrointestinal conditions but could be of use to human fecal microbes, thereby lowering the pH and increasing the production of short-chain fatty acids (SCFAs) of the gut microenvironment and altering the composition of the gut microbiota. The relative abundance of , and increased significantly, potentially contributing to the degradation of TFPS-1-3p.
PubMed: 38178927
DOI: 10.1016/j.fochx.2023.101058 -
Ecotoxicology and Environmental Safety Jan 2024Prenatal exposure to per- and polyfluoroalkyl substances (PFASs) has been reported to be linked to a series of adverse health outcomes in mothers and their children. As...
Prenatal exposure to per- and polyfluoroalkyl substances (PFASs) has been reported to be linked to a series of adverse health outcomes in mothers and their children. As the gut microbiota is a sensitive biomarker for assessing the toxicity of environmental contaminants, this study attempted to investigate whether prenatal PFASs exposure was associated with the gut microbiota of infants. Based on the Shanghai-Minhang Birth Cohort Study, this prospective cohort study included 69 mother-infant pairs. Fasting blood samples were collected from pregnant women for the PFASs assay. We collected fecal samples of infants at 1 year of age and analyzed the V3-V4 hypervariable region of the bacterial 16 S rRNA gene by high-throughput sequencing. Among the detected 11 PFASs, the concentration of perfluorooctanoic acid (22.19 ng/mL) was the highest, followed by perfluorooctane sulfonic acid (12.08 ng/mL). Compared with infants whose mothers' total PFASs concentrations during pregnancy were at the 40th percentile or lower (reference group), the species richness and diversity of microbiota were lower in infants prenatally exposed to a high level of PFASs (the sum of PFASs concentrations above the 60th percentile). Prenatal exposure to PFASs was associated with a higher proportion of Acidaminococcaceae, Acidaminococcus, Megamonas, Megasphaera micronuciformis and Megamonas funiformis in infants. The changes of the species have been suggested to be associated with immune and metabolic dysfunction in humans. Functional alterations of gut microbiota due to PFASs exposure were dominated by an enrichment of butanoate metabolism. Our preliminary findings may shed light on the potential role of the microbiota underlying the well-known impact of prenatal PFASs exposure on health outcomes of humans in later life.
Topics: Female; Humans; Infant; Pregnancy; Alkanesulfonic Acids; China; Cohort Studies; Environmental Pollutants; Fluorocarbons; Gastrointestinal Microbiome; Prenatal Exposure Delayed Effects; Prospective Studies; Vitamins
PubMed: 38159339
DOI: 10.1016/j.ecoenv.2023.115891 -
The Science of the Total Environment Feb 2024Megasphaera hexanoica is a bacterial strain following the reverse β-oxidation pathway to synthesize caproate (CA) using lactate (LA) as an electron donor (ED) and...
Megasphaera hexanoica is a bacterial strain following the reverse β-oxidation pathway to synthesize caproate (CA) using lactate (LA) as an electron donor (ED) and acetate (AA) or butyrate (BA) as electron acceptors (EA). Differences in the type and concentration of EA lead to distinctions in product distribution and energy bifurcation of carbon fluxes in ED pathways, thereby affecting CA production. In this study, the effect of various ratios of AA, BA, and AA+BA as EA on carbon flux and CA specific titer during the carbon chain elongation in M. hexanoica was explored. The results indicated that the maximum levels of CA were 18.81 mM and 31.48 mM when the molar ratios of LA/AA and LA/BA were 10:1 and 3:1, respectively. Meanwhile, when AA and BA were used as combined EA (LA, AA, and BA molar amounts of 100, 23, and 77 mM), a maximum CA production of 39.45 mM was obtained. Further analysis revealed that the combined EA exhibited a CA production carbon flux of 49 % (4.3 % and 19.5 % higher compared to AA or BA, respectively) and a CA production specific titer of 45.24 mol (80.89 % and 58.51 % higher compared to AA or BA, respectively), indicating that the effective carbon utilization rate and CA production efficiency were greatly improved. Finally, a scaled-up experiment was conducted in a 1.2 L (working volume) automated bioreactor, implying high biomass (optical density at 600 nm or OD = 1.809) and a slight decrease in CA production (28.45 mM). A decrease in H production (4.11 g/m) and an increase in CO production (0.632 g/m) demonstrated the appropriate metabolic adaptation of M. hexanoica to environmental changes such as stirring shear.
Topics: Fermentation; Carbon; Electrons; Bioreactors; Butyrates; Acetates; Caproates; Megasphaera
PubMed: 38141983
DOI: 10.1016/j.scitotenv.2023.169509 -
Animal Nutrition (Zhongguo Xu Mu Shou... Mar 2024Skatole, a strong fecal odor substance, is generated through microbial degradation of tryptophan in the animal hindgut. It easily accumulates in adipose tissue and...
Skatole, a strong fecal odor substance, is generated through microbial degradation of tryptophan in the animal hindgut. It easily accumulates in adipose tissue and affects meat quality. In this study, the effect of mulberry leaf supplementation on skatole in finishing pigs was studied. In a 35-day trial, 20 finishing pigs (barrows and gilts) were fed with a basal diet or basal diet with 6% mulberry leaves. Growth performance of the pigs ( = 10) was automatically recorded by a performance-testing feeder system and 8 pigs in each treatment were slaughtered and sampled for the remaining tests. Skatole and short-chain fatty acids were detected using HPLC and gas chromatography, respectively. Fecal microbiota were analyzed using 16S rRNA gene sequencing. The metabolomics analysis of feces and serum was performed with UHPLC-MS/MS. The major cytochrome P450 (CYP) enzymes that catalyze skatole degradation in the liver were tested by using RT-PCR and Western blot. Effects of major bioactive compounds in mulberry leaves on the genes were verified in the hepatic cell line HepG2 in an in vitro test ( = 3). In finishing pigs, mulberry leaf supplementation had no significant effect on the average daily gain, average daily feed intake, and feed conversion ratio ( > 0.05), but reduced skatole levels in feces, serum, and backfat ( < 0.05), and increased acetic acid levels in feces ( = 0.027). Mulberry leaf supplementation decreased the relative abundance of the skatole-producing bacteria and ( < 0.05). Indole-3-acetic acid, the intermediate that is essential for skatole production, was significantly reduced in feces by mulberry leaf supplementation ( < 0.05) and was positively correlated with skatole content in feces ( = 0.004). In pigs treated with mulberry leaves, liver expression was increased ( < 0.05) and was negatively correlated with skatole content in backfat ( = 0.045). The in vitro test demonstrated that mulberry leaf polyphenols and polysaccharides could directly stimulate expression in hepatic cells. These findings suggest that mulberry leaf supplementation reduces skatole production and deposition in finishing pigs by regulating the gut microbiota and promoting skatole degradation in liver.
PubMed: 38131029
DOI: 10.1016/j.aninu.2023.05.018 -
Applied and Environmental Microbiology Jan 2024Butyrate, a physiologically active molecule, can be synthesized through metabolic interactions among colonic microorganisms. Previously, in a fermenting trial of human...
Butyrate, a physiologically active molecule, can be synthesized through metabolic interactions among colonic microorganisms. Previously, in a fermenting trial of human fecal microbiota, we observed that the butyrogenic effect positively correlated with the increasing population and an unidentified species. Therefore, we hypothesized that a cross-feeding phenomenon exists between and , where is the butyrate producer, and its growth relies on the metabolites generated by . To validate this hypothesis, three bacterial species (, , and ) were isolated from fecal cultures fermenting hydrolyzed xylan; pairwise cocultures were conducted between the and isolates; the microbial interactions were determined based on bacterial genome information, cell growth, substrate consumption, metabolite quantification, and metatranscriptomics. The results indicated that two isolates contained distinct gene clusters for xylan utilization and expressed varying substrate preferences. In contrast, alone scarcely grew on the xylose-based substrates. The growth of was significantly elevated by coculturing it with bifidobacteria, while the two species responded differently in the kinetics of cell growth and substrate consumption. Coculturing led to the depletion of lactate and increased the formation of butyrate. An RNA-seq analysis further revealed the upregulation of genes involved in the lactate utilization and butyrate formation pathways. We concluded that lactate generated by through catabolizing xylose fueled the growth of and triggered the synthesis of butyrate. Our findings demonstrated a novel cross-feeding mechanism to generate butyrate in the human colon.IMPORTANCEButyrate is an important short-chain fatty acid that is produced in the human colon through microbial fermentation. Although many butyrate-producing bacteria exhibit a limited capacity to degrade nondigestible food materials, butyrate can be formed through cross-feeding microbial metabolites, such as acetate or lactate. Previously, the literature has explicated the butyrate-forming links between and and between and . In this study, we provided an alternative butyrate synthetic pathway through the interaction between and is a species named in 2014 and is indigenous to the human intestinal tract. Scientific studies explaining the function of in the human colon are still limited. Our results show that proliferated based on the lactate generated by bifidobacteria and produced butyrate as its end metabolic product. The pathways identified here may contribute to understanding butyrate formation in the gut microbiota.
Topics: Humans; Lactic Acid; Bifidobacterium; Xylans; Xylose; Butyrates; Megasphaera; Fermentation
PubMed: 38126785
DOI: 10.1128/aem.01019-23