Gastrointestinal Tract Microbiota Research Articles

Third-party fecal microbiota transplantation for high-risk treatment-naïve acute GVHD of the lower GI tract

AbstractDisruption of the intestinal microbiome is observed with acute graft-versus-host disease (GVHD) of the lower gastrointestinal (LGI) tract, and fecal microbiota transplantation (FMT) has successfully cured steroid-refractory cases. In this open-label, single-arm, pilot study, third-party, single-donor FMT was administered in combination with systemic corticosteroids to participants with high-risk acute LGI GVHD, with a focus on treatment-naïve cases. Participants were scheduled to receive 1 induction dose (15 capsules per day for 2 consecutive days), followed by 3 weekly maintenance doses, consisting of 15 capsules per dose. The primary end point of the study was feasibility, which would be achieved if ≥80% of participants able to swallow ≥40 of the 75 scheduled capsules. Ten participants (9 treatment-naïve; 1 steroid-refractory) were enrolled and treated. The study met the primary end point, with 9 of 10 participants completing all eligible doses. Organ-specific LGI complete response rate at day 28 was 70%. Initial clinical response was observed within 1 week for all responders, and clinical responses were durable without recurrent LGI GVHD in complete responders. Exploratory analyses suggest that alpha diversity increased after FMT. Although recipient microbiome composition never achieved a high degree of donor similarity, expansion of donor-derived species and increases in tryptophan metabolites and short-chain fatty acids were observed within the first 7 days after FMT. Investigation into the use of microbiome-targeted interventions earlier in the treatment paradigm for acute LGI GVHD is warranted. This trial was registered at www.ClinicalTrials.gov as #NCT04139577.

Fecal microbiota impacts development of Cryptosporidium parvum in the mouse

The dependence of Cryptosporidium parasites on host cell metabolites suggests that the development of nutritional interventions to limit parasite proliferation should be feasible. Based on this concept, we are testing dietary interventions to affect the enterocytes’ metabolism in a manner that limits intracellular multiplication of the parasite. We hypothesize that changes in the metabolic pathways encoded by the gastro-intestinal tract microbiota may restrict parasite proliferation. To identify taxonomic and metabolic features of the microbiota associated with severity of cryptosporidiosis, as determined by estimating oocyst output, we characterized the fecal microbiota from mice experimentally infected with Cryptosporidium parvum. To eliminate the confounding effect of the interaction between co-housed mice, as well as facilitate the identification of microbiota markers associated with severity of cryptosporidiosis, fecal microbiota from individually caged mice were analyzed. Variation partitioning analysis applied to 16S sequence data from 25 mice belonging to four experiments shows that experiment was by far the biggest source of microbiota variation. Severity of cryptosporidiosis explained a smaller, though significant, fraction of microbiota variation. Notably, this effect was significant in the pre-patent phase of the infection, before mice excreted oocysts. These results are consistent with the pre-patent intestinal microbiota having a modest, but measurable, effect on cryptosporidiosis.

Prevalence and characteristics of ESBL-producing Escherichia coli in clinically healthy pigs: implications for antibiotic resistance spread in livestock.

This study aimed to compare and characterize the resistance profile and the presence of extended-spectrum beta-lactamase (ESBL) related genes in Escherichia coli isolated from healthy finishing pigs fed with or without antibiotics in their diets. A total of 27 ceftiofur-resistant E. coli isolates were obtained from 96 healthy pigs. The antibiotic resistance profile was tested, and all 27 isolates were classified as multidrug-resistant (MDR). A high proportion of isolates were resistant to cephalosporins, ampicillin, ciprofloxacin, and tetracyclines. The ESBL production was observed in 85% of isolates by double-disc synergy test. The MDR-E. coli isolates harbored ESBL genes, such as blaTEM, blaCTX-M-1, blaCTX-M-2, and blaCTX-M-8,25. In addition, other antibiotics resistance genes (ARGs) were also detected, such as sul2, ant(3″)-I, tetA, and mcr-1. The mobilization of the blaCTX-M gene was confirmed for nine E. coli isolates by conjugation assays. The presence of blaCTX-M on mobile genetic elements in these isolates was demonstrated by Southern blot hybridization, and the resistance to cephalosporins was confirmed in the transconjugants. Our results indicate the prevalence of CTX-M-producing E. coli strains harboring mobile genetic elements in the normal microbiota of healthy pigs. These findings highlight the significance of ESBL genes as a global health concern in livestock and the potential spread of antimicrobial resistance to other members of the gastrointestinal tract microbiota.

The multi-kingdom microbiome catalog of the chicken gastrointestinal tract

Chicken is an important food animal worldwide and plays an important role in human life by providing meat and eggs. Despite recent significant advances in gut microbiome studies, a comprehensive study of chicken gut bacterial, archaeal, and viral genomes remains unavailable. In this study, we constructed a chicken multi-kingdom microbiome catalog (CMKMC), including 18,201 bacterial, 225 archaeal, and 33,411 viral genomes, and annotated over 6,076,006 protein-coding genes by integrating 135 chicken gut metagenomes and publicly available metagenome-assembled genomes (MAGs) from ten countries. We found that 812 and 240 MAGs in our dataset were putative novel species and genera, respectively, far beyond what was previously reported. The newly unclassified MAGs were predominant in Phyla Firmicutes_A (n = 263), followed by Firmicutes (n = 126), Bacteroidota (n = 121), and Proteobacteria (n = 87). Most of the classified species-level viral operational taxonomic units belong to Caudovirales. Approximately, 63.24 % of chicken gut viromes are predicted to infect two or more hosts, including complete circular viruses. Moreover, we found that diverse auxiliary metabolic genes and antibiotic resistance genes were carried by viruses. Together, our CMKMC provides the largest integrated MAGs and viral genomes from the chicken gut to date, functional insights into the chicken gastrointestinal tract microbiota, and paves the way for microbial interventions for better chicken health and productivity.

Understanding gut microbiome-based machine learning platforms: A review on therapeutic approaches using deep learning.

Human beings possess trillions of microbial cells in a symbiotic relationship. This relationship benefits both partners for a long time. The gut microbiota helps in many bodily functions from harvesting energy from digested food to strengthening biochemical barriers of the gut and intestine. But the changes in microbiota composition and bacteria that can enter the gastrointestinal tract can cause infection. Several approaches like culture-independent techniques such as high-throughput and meta-omics projects targeting 16S ribosomal RNA (rRNA) sequencing are popular methods to investigate the composition of the human gastrointestinal tract microbiota and taxonomically characterizing microbial communities. The microbiota conformation and diversity should be provided by whole-genome shotgun metagenomic sequencing of site-specific community DNA associating genome mapping, gene inventory, and metabolic remodelling and reformation, to ease the functional study of human microbiota. Preliminary examination of the therapeutic potency for dysbiosis-associated diseases permits investigation of pharmacokinetic-pharmacodynamic changes in microbial communities for escalation of treatment and dosage plan. Gut microbiome study is an integration of metagenomics which has influenced the field in the last two decades. And the incorporation of artificial intelligence and deep learning through "omics-based" methods and microfluidic evaluation enhanced the capability of identification of thousands of microbes.

The Efficacy of Selected Probiotic Strains and Their Combination to Inhibit the Interaction of Adherent-Invasive Escherichia coli (AIEC) with a Co-Culture of Caco-2:HT29-MTX Cells.

The gastrointestinal tract's microbiota plays a crucial role in human health, with dysbiosis linked to the development of diseases such as inflammatory bowel disease (IBD). Whilst the pathogenic mechanisms underlying IBD remain poorly characterised, adherent-invasive Escherichia coli (AIEC) has been implicated as a microbiological factor in disease pathogenesis. These strains show an enhanced ability to diffusely adhere to and invade intestinal epithelial cells, along with the ability to survive and replicate within macrophages. Probiotics, such as Lactobacillus strains, have been identified as potential treatment options due to their abilities to compete with pathogens for binding sites and regulate the host immune response. In this study, we used four well-characterised Lactobacillus strains and their combination to test their ability to inhibit the adhesion, invasion, and translocation of a well-characterized AIEC strain, F44A-1, in a co-culture of Caco-2 and HT29-MTX cell lines representing the gut epithelium. The results demonstrated that the pre-inoculation of the probiotic candidates 90 min prior to the introduction of the AIEC was more effective in inhibiting AIEC interaction than the co-inoculation of the strains. While the individual probiotic strains greatly reduced AIEC colonisation and invasion of the co-cultured cells, their combination was only more effective in reducing the translocation of the AIEC. These results suggest that probiotics are more effective when used prophylactically against pathogens and that the combination of strains may enhance their efficacy against AIEC translocation once used as a prophylactic measure.

Effect of a Lactobacilli-Based Direct-Fed Microbial Product on Gut Microbiota and Gastrointestinal Morphological Changes.

The calf's gastrointestinal tract (GIT) microbiome undergoes rapid shifts during early post-natal life, which can directly affect calf performance. The objectives of this study were to characterise and compare differences in the establishment and succession of GIT microbiota, GIT morphological changes, and the growth of dairy calves from birth until weaned. Forty-four newborn Holstein-Friesian calves were randomly selected and assigned to Treatment (TRT) and Control (CON) groups. The TRT group calves received a once-daily dose of a direct-fed microbial (DFM) liquid product containing Lacticaseibacillus paracasei, Lentilactobacillus buchneri, and Lacticaseibacillus casei, all formerly known as Lactobacillus. Fresh faecal samples were manually taken from the rectum of all calves, and gross necropsy was performed on the forestomachs and gastrointestinal tracts. Bacterial DNA was extracted from frozen faecal samples for 16S rRNA gene amplicon sequencing. Calves in the TRT group had greater live weights (p = 0.02) at weaning compared with calves in the CON group (mean = 69.18 kg, SD = 13.37 kg). The average daily live weight gain (ADG) and total feed intake were similar between the two groups. Calves in the TRT group had greater duodenum, abomasum, and reticulum weights (p = 0.05). Rumen and intestinal development (p < 0.05) and faecal microbial diversity (p < 0.05) were more pronounced in the TRT group. The relative abundances of eight genera differed (p < 0.001) between the groups. Supplementing calves with the LAB-based DFM increased live weight at weaning and had a more pronounced effect on the development of rumen and the gastrointestinal tract and on microbiota diversity and evenness. Future work is needed to better understand the potential association of LAB-DFM products on gut mucosa-associated microbiota.

A pH‐Sensitive Smart Monomer Prevents Oral Cancer Progression

Oral squamous cell carcinoma (OSCC) is a prevalent cancer worldwide, and the development of anti‐OSCC materials is urgent. The tumor microenvironment has been identified as a significant characteristic of cancer, with the pHe value in OSCC ranging from 6.56 to 6.97. Given the acidic nature of OSCC, the creation of pH‐sensitive antitumor materials has become a prominent area of research. A pH‐sensitive tertiary amine monomer, dodecylmethylaminoethyl methacrylate (DMAEM), has been previously synthesized. This study aims to evaluate the impact of DMAEM on OSCC. The results demonstrated that DMAEM inhibited the proliferation, migration, and invasion of OSCC cells. Furthermore, it promoted apoptosis and autophagy of OSCC cells, with its anti‐OSCC effect being strengthened in the acidic environment. In a subcutaneous transplantation tumor model, DMAEM inhibited the growth of OSCC and expression of Ki‐67. The analysis of 16S rDNA sequencing data revealed that DMAEM had no significant impact on the Alpha/Beta diversity of the gastrointestinal tract microbiota in mice and had minimal effect on its composition. Overall, this study suggests that DMAEM exhibits pH‐responsive behavior in the acidic tumor microenvironment, effectively inhibiting OSCC without disturbing the gastrointestinal microbiota. These findings highlight the potential of DMAEM for clinical applications in OSCC treatment.

Comparison of Cecal Microbiome in Healthy and Naturally Infected Broiler with Different Salmonella serotypes

The gastrointestinal tract (GIT) of chickens is rich of complex and diverse microbiota that is important to immune system development, pathogen exclusion, and digestion and absorption of nutrients. The 16S rRNA sequencing is an effective method for studying the ecological and biological functions of the chicken GIT microbiota. The current study aimed to assess the composition and diversity of gut microbiome of healthy broiler chicken in comparison to those infected with Salmonella. A total of 100 Broiler chickens’ whole cecal samples were randomly collected, which divided into 50 healthy broiler chicken (HBC) and 50 diseased broiler chicken (DBC), The bacteriological examination of samples revealed that 4/100 (4 %) of the examined samples were identified as S. enterica species Salmonella typhimurium represented 75% while Salmonella enterditis showed 25%. All the isolates were confirmed to be Salmonella using a primer targeting invA gene. A total of 2 whole cecal samples from each group were subjected to 16S rRNA sequencing with bioinformatics analysis to investigate the composition and the diversity of chicken microbiome. The results showed a significant abundance and diversity in the microbiota composition of HBC when compared with that of DBC. It reflected decreased numbers of beneficial bacterial agents in DBC which increased its liability to acquire infection. Salmonella altered the microbiome composition of infected chickens and using advanced molecular techniques will help to investigate the microbial composition in a collective manner that helps in keeping birds healthy to promote productivity and incomes.

Ligilactobacillus Salivarius improve body growth and anti-oxidation capacity of broiler chickens via regulation of the microbiota-gut-brain axis

Certain strains of probiotic bacteria can secret functional substances namely digestive enzymes and functional peptides to regulate physiological conditions such as digestion and anti-oxidation, which are often incorporated in industrial broiler chick production. However, few studies have detailed the action mechanisms and effects of these bacteria on regulating growth and anti-oxidation levels in broiler chickens. Ligilactobacillus salivarius is a strain of probiotic bacteria used as dietary supplement. In the present study, Ligilactobacillus salivarius was evaluated for its secreted digestive enzymes in vitro. To detailed evaluate the action mechanisms and effects of gastrointestinal tract (GIT) microbiota on alleviating anti-oxidation levels of broiler chickens through the gut-brain axis. Ligilactobacillus salivarius was cultured and supplemented in the food of broilers to evaluate the probiotic effect on growth and anti-oxidation by modulation of gut microbial composition and its functional metabolites using metagenomic and metabolomic assays. Biochemical results showed that Ligilactobacillus salivarius secreted digestive enzymes: protease, lipase, and amylase. Broiler chickens with Ligilactobacillus salivarius supplemented for 42 days, showed increased body weights, a reduced oxidative status, decreased malondialdehyde levels, and improved activities rates of total superoxide dismutase, glutathione peroxidase IIand IV improved. The microbial composition of caecum was more abundant than those broiler without probiotics supplementation, owing 400 of total number (489) of bacterial operational taxonomic units (OTU). The genera of Lactobacillus, Megamonas, Ruminoccoccaceae, Ruminococcus, Alistipes and Helicobacter shared the dominant proportion of Candidatus _Arthromitus compared with the control chickens. These functional bacteria genera assisted in the transportation and digestion of amino acids, carbohydrates, and ions, synthesis of cellular membranes, and anti-oxidation. Uncultured_organism_g_ Anaerosporobacter, Lactobacillus salivarius, uncultured_bacterium_g_ Ruminococcaceae_UCG-014, uncultured_bacterium_g_ Peptococcus were strongly and positively correlated with body growth performance and anti-oxidation. A metabonomic assay suggested that the secreted of gamma-aminobutyric acid and monobactam was metabolized according to the Kyoto Encyclopedia of Genes and Genomes analysis. In conclusion, Ligilactobacillus salivarius optimized microbial composition of the caecum and secreted functional peptides through gut-brain axis to improve the body growth and antioxidation of broiler chicken.

Unveiling the Gut Microbiome: How Junk Food Impacts the Gut.

The human gut microbiome, a complex community of microorganisms, profoundly influences human health and disease. Bacteroidetes and Firmicutes make up the majority of the normal human gut microbiota.These microorganisms wield considerable influence over our physiological functions, impacting both our well-being and our susceptibility to disease. The surge of interest in the gut microbiome over the past decade has been remarkable. Once overlooked, the gastrointestinal tract's microbiota has gained recognition for its significance in maintaining optimal health. The food industry has capitalized on this, flooding the market with "probiotic" and "fermented" products. This article aims to provide a critical review of the current literature on the gut microbiome and its significance in human health, with a particular focus on the impact of dietary choices, especially junk food, on the composition and function of the gut microbiota. Microbes possess the remarkable ability to unlock nutrients from otherwise indigestible substances. The gut microbiome of individuals who consume healthy foods and those who prefer junk food varies significantly. Healthy diets promote a diverse and beneficial gut microbiome, while junk food consumption often leads to a less diverse microbiome with negative consequences for health.

MICROBIOMES OF HUMAN, LIVESTOCK ANIMAL GASTROINTESTINAL TRACTS AND OF FOOD PRODUCTS AND COMPOUND FEEDS: CONNECTIONS AND IMPACTS. PART 1

The physiological mechanisms of food digestion in humans and feed digestion in animals are determined by the structure of the gastrointestinal tract (GIT) and diet. Accordingly, humans are omnivores, while domestic animals are divided into ruminants, monogastric herbivores, and monogastric omnivores, and birds are divided into herbivores (geese, ducks) and omnivores (chickens, turkeys, etc.). The digestion and assimilation of food and feed depends not only on own mechanisms but also on the GIT microbiome. The location of the most important part of this microbiome and its composition depend on the species: in ruminants, it is the rumen microbiome, in horses – the cecum (it is a counterpart of the rumen), in humans and pigs – the intestine, in birds – the crop, gizzard and cecum. These microbiomes are in constant close connection with the host organism, and this connection is realized through numerous molecular mechanisms of interaction between bacterial cells and host cells and tissues. GIT microorganisms not only help to assimilate food (feed) by partially digesting it, but also secrete biologically active substances that have protective, stimulating and other beneficial effects for the host. In adult hosts, this GIT microbiota is well developed and stable, while in children and young animals it can be much more mobile and vulnerable. Food and feed contain many components that are a favorable medium for the development of microorganisms. Raw materials and components of animal origin are the most contaminated, while vegetable raw materials and components, as well as premixes, contain significantly fewer microorganisms. Among the microorganisms colonizing raw materials, food and feeds, coliforms, salmonellae and molds may be present. In young animals, the feed microbiota ingested into the GIT, even without taking into account obligate or opportunistic pathogens, can cause shifts or changes in the digestive microenvironment towards deterioration, which will have a corresponding impact on the efficiency of feed absorption and, through it, on the efficiency of feeding and animal productivity.

The role of the microbiota of the gastrointestinal tract in the pathogenesis of inflammatory bowel diseases

In recent years, with the rapid development of molecular biology, genomics, high-performance sequencing technology and bioinformatic analysis technology, there has been an active study of a previously overlooked “organ” – the intestinal microbiota (GM). It is known that the microbiota of the human gastrointestinal tract plays a key role in metabolic, physiological, immunological and digestive processes. Microbial composition and colonization, in turn, depend on factors such as the neonatal delivery method, breastfeeding, nutrition, antibiotic treatment and environmental exposure at an early age. Also, one of the factors influencing the maintenance of homeostasis is the relationship between bacterial species or communities of species inside and outside the microbiome. Dysbiosis is the key to understanding the etiology of various diseases. Although the pathogenesis of IBD has not been fully studied, in patients with this pathology, inflammation of the gastrointestinal tract is a common sign of intestinal dysbiosis. Currently, there is a lot of evidence that intestinal dysbiosis leads to a violation of immune tolerance, which can cause or complicate the course of IBD. Thus, research is needed to clarify the role of microbiota in the pathogenesis of diseases. Based on changes in the intestinal microbiota, new diagnostic tools and possible treatment methods can be developed.

Erythrocytic α-Synuclein and the Gut Microbiome: Kindling of the Gut-Brain Axis in Parkinson's Disease.

Progressive spreading of α-synuclein via gut-brain axis has been hypothesized in the pathogenesis of Parkinson's disease (PD). However, the source of seeding-capable α-synuclein in the gastrointestinal tract (GIT) has not been fully investigated. Additionally, the mechanism by which the GIT microbiome contributes to PD pathogenesis remains to be characterized. We aimed to investigate whether blood-derived α-synuclein might contribute to PD pathology via a gut-driven pathway and involve GIT microbiota. The GIT expression of α-synuclein and the transmission of extracellular vesicles (EVs) derived from erythrocytes/red blood cells (RBCs), with their cargo α-synuclein, to the GIT were explored with various methods, including radioactive labeling of RBC-EVs and direct analysis of the transfer of α-synuclein protein. The potential role of microbiota on the EVs transmission was further investigated by administering butyrate, the short-chain fatty acids produced by gut microbiota and studying mice with different α-synuclein genotypes. This study demonstrated that RBC-EVs can effectively transport α-synuclein to the GIT in a region-dependent manner, along with variations closely associated with regional differences in the expression of gut-vascular barrier markers. The investigation further revealed that the infiltration of α-synuclein into the GIT was influenced significantly by butyrate and α-synuclein genotypes, which may also affect the GIT microbiome directly. By demonstrating the transportation of α-synuclein through RBC-EVs to the GIT, and its potential association with gut-vascular barrier markers and gut microbiome, this work highlights a potential mechanism by which RBC α-synuclein may impact PD initiation and/or progression. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

The multi-kingdom microbiome of the goat gastrointestinal tract

BackgroundGoat is an important livestock worldwide, which plays an indispensable role in human life by providing meat, milk, fiber, and pelts. Despite recent significant advances in microbiome studies, a comprehensive survey on the goat microbiomes covering gastrointestinal tract (GIT) sites, developmental stages, feeding styles, and geographical factors is still unavailable. Here, we surveyed its multi-kingdom microbial communities using 497 samples from ten sites along the goat GIT.ResultsWe reconstructed a goat multi-kingdom microbiome catalog (GMMC) including 4004 bacterial, 71 archaeal, and 7204 viral genomes and annotated over 4,817,256 non-redundant protein-coding genes. We revealed patterns of feeding-driven microbial community dynamics along the goat GIT sites which were likely associated with gastrointestinal food digestion and absorption capabilities and disease risks, and identified an abundance of large intestine-enriched genera involved in plant fiber digestion. We quantified the effects of various factors affecting the distribution and abundance of methane-producing microbes including the GIT site, age, feeding style, and geography, and identified 68 virulent viruses targeting the methane producers via a comprehensive virus-bacterium/archaea interaction network.ConclusionsTogether, our GMMC catalog provides functional insights of the goat GIT microbiota through microbiome-host interactions and paves the way to microbial interventions for better goat and eco-environmental qualities.-Pdb_6YZpzy_mmd53S_tihVideo

Effect of grape pomace supplement on growth performance, gastrointestinal microbiota, and methane production in Tan lambs.

Grape pomace (GP), a by-product in wine production, is nutritious and can be used as a feed ingredient for ruminants; however, its role in shaping sheep gastrointestinal tract (GIT) microbiota is unclear. We conducted a controlled trial using a randomized block design with 10 Tan lambs fed a control diet (CD) and 10 Tan lambs fed a pelleted diet containing 8% GP (dry matter basis) for 46 days. Rumen, jejunum, cecum, and colon bacterial and archaeal composition were identified by 16S rRNA gene sequencing. Dry matter intake (DMI) was greater (p < 0.05) in the GP than CD group; however, there was no difference in average daily gain (ADG, p < 0.05) and feed conversion ratio (FCR, p < 0.05) between the two groups. The GP group had a greater abundance of Prevotella 1 and Prevotella 7 in the rumen; of Sharpe, Ruminococcaceae 2, and [Ruminococcus] gauvreauii group in the jejunum; of Ruminococcaceae UCG-014 and Romboutsia in the cecum, and Prevotella UCG-001 in the colon; but lesser Rikenellaceae RC9 gut group in the rumen and cecum, and Ruminococcaceae UCG-005 and Ruminococcaceae UCG-010 in the colon than the CD group. The pathways of carbohydrate metabolism, such as L-rhamnose degradation in the rumen, starch and glycogen degradation in the jejunum, galactose degradation in the cecum, and mixed acid fermentation and mannan degradation in the colon were up-graded; whereas, the pathways of tricarboxylic acid (TCA) cycle VIII, and pyruvate fermentation to acetone in the rumen and colon were down-graded with GP. The archaeal incomplete reductive TCA cycle was enriched in the rumen, jejunum, and colon; whereas, the methanogenesis from H2 and CO2, the cofactors of methanogenesis, including coenzyme M, coenzyme B, and factor 420 biosynthesis were decreased in the colon. The study concluded that a diet including GP at 8% DM did not affect ADG or FCR in Tan lambs. However, there were some potential benefits, such as enhancing propionate production by microbiota and pathways in the GIT, promoting B-vitamin production in the rumen, facilitating starch degradation and amino acid biosynthesis in the jejunum, and reducing methanogenesis in the colon.

Effects of rearing mode on gastro-intestinal microbiota and development, immunocompetence, sanitary status and growth performance of lambs from birth to two months of age

BackgroundArtificial rearing system, commonly used in prolific sheep breeds, is associated to increased mortality and morbidity rates before weaning, which might be linked to perturbations in digestive tract maturation, including microbiota colonization. This study evaluated the effect of rearing mode (mothered or artificially reared) on the establishment of the rumen and intestinal microbiome of lambs from birth to weaning. We also measured immunological and zootechnical parameters to assess lambs’ growth and health. GIT anatomy as well as rumen and intestinal epithelium gene expression were also analysed on weaned animals to assess possible long-term effects of the rearing practice.ResultsTotal VFA concentrations were higher in mothered lambs at 2 months of age, while artificially-reared lambs had lower average daily gain, a more degraded sanitary status and lower serum IgG concentration in the early growth phase. Metataxonomic analysis revealed higher richness of bacterial and eukaryote populations in mothered vs. artificially-reared lambs in both Rumen and Feces. Beta diversity analysis indicated an evolution of rumen and fecal bacterial communities in mothered lambs with age, not observed in artificially-reared lambs. Important functional microorganisms such as the cellulolytic bacterium Fibrobacter succinogenes and rumen protozoa did not establish correctly before weaning in artificially-reared lambs. Enterobacteriaceae and Escherichia coli were dominant in the fecal microbiota of mothered lambs, but main E. coli virulence genes were not found differential between the two groups, suggesting they are commensal bacteria which could exert a protective effect against pathogens. The fecal microbiota of artificially-reared lambs had a high proportion of lactic acid bacteria taxa. No difference was observed in mucosa gene expression in the two lamb groups after weaning.ConclusionsThe rearing mode influences gastrointestinal microbiota and health-associated parameters in offspring in early life: rumen maturation was impaired in artificially-reared lambs which also presented altered sanitary status and higher risk of gut dysbiosis. The first month of age is thus a critical period where the gastrointestinal tract environment and microbiota are particularly unstable and special care should be taken in the management of artificially fed newborn ruminants.

Mysterious &lt;i&gt;Akkermansia muciniphila&lt;/i&gt;. What do we know about it? A review

"Microbes and humans" is a topic that has been continuously studied over the past decade. Numerous recent studies show that quantitative and qualitative changes in the composition of the gastrointestinal tract microbiota have direct and indirect effects on metabolic changes in the host. Many countries are researching the microbiome and opportunities to influence health through environmental modification and introducing a probiotic, a metabiotic, or a synbiotic into the body. Considerable attention is paid to metabolic disorders and obesity, as these are issues that are becoming a progressive global epidemic. More than 2 billion people are overweight and obese, and many experts continue to look for promising methods to combat it. A special group of high risk for obesity is children. Statistics show a steady upward trend of obesity in children. Over the past 10 years, this trend has shown a rapid pace: from 6.7%, according to 2010, to 9.1% by 2020. In this context, Akkermansia muciniphila attracts special attention among all bacteria inhabiting the gastrointestinal tract due to its potential to treat insulin resistance, obesity, and diabetes mellitus. This article reviews new research on the A. muciniphila effects on the host and ways to correct metabolism using probiotics.

The digestive tract histology and geographical distribution of gastrointestinal microbiota in yellow-feather broilers

Exhaustive understanding of intestinal physiological characteristics is the critical precondition for the improvement of intestinal health and growth performance of yellow-feather broilers (YFB). As a vital part of gastrointestinal tract, the symbiotic, complex, and variable microbiota have a profound effect on the nutrition, immunity, health, and production of broilers. Hence, the development status of proventriculus, jejunum, and cecum, and spatial heterogeneity of bacterial community in crop, proventriculus, gizzard, jejunum, cecum, and rectum of adult YFB were detected in our study. The results revealed that proventriculus, jejunum, and cecum of broilers are well-developed based on morphological observation. The Chao and Shannon indexes in cecum and rectum are notably higher than other sections and their microbiota structure is also distinct from foregut. Firmicutes and Lactobacillus are the predominant phylum and genus in all gastrointestinal sections, respectively. As feature species of crop, Lactobacillus spp. mainly settle in foregut, whereas some Clostridia species (unclassified Lachnospiraceae, Faecalibacterium, Romboutsia and so on) are characteristic and more abundant in cecum and rectum. Interestingly, there are 2 Ruminococcus torques strains positively and negatively correlated with cecum development, respectively. In a whole, our findings reveal the specialized digestive physiology and regional distribution of intestinal microbiota in YFB, which provides a reference for the future study on the improvement of growth performance and intestinal development through microbiota manipulation in yellow-feather broilers.

Perturbations in gastrointestinal tract microbiota composition and function in individuals with yellow-greasy tongue coating

ObjectiveTo study the composition and function of tongue coating (TC) and gastrointestinal tract (GIT) microbiota in participants with yellow-greasy tongue coating (YGTC), and to explore the representative metabolite markers and pathways in this group. MethodsSubjects with YGTC or thin-white tongue coating (TWTC) were recruited from December 1, 2021 to October 30, 2022, and the TC and fecal samples were collected. Samples were subjected to both whole-genome shotgun (WGS), and 16S rRNA gene sequencing. The α-diversity analysis, principal component analysis (PCA), and Spearman correlation analysis were performed for two groups. Ultra-performance liquid chromatography combined with tandem mass spectrometry (UPLC–MS/MS) analysis was used to analyze metabolomics and enrichment of metabolic pathways. ResultsThe results revealed 20 YGTC participates and 19 TWTC participates. At the genus level, the dominant bacterial species of TC flora and intestinal flora in the two groups were roughly the same, but the relative kurtosis difference was marked, and the abundance of potentially pathogenic bacteria in TC and fecal samples of YGTC subjects was higher. There were 9 down-regulated microorganisms in the TC samples, 26 down-regulated microorganisms, and 6 up-regulated microorganisms in YGTC subjects. The α-diversity analysis indicated that the Chao and abundance-based coverage estimator (ACE) indices of TC bacteria in the YGTC subjects showed a decreasing trend, but the difference was not statistically significant (P > 0.05). The α-diversity of fecal samples and the Chao and ACE indices decreased significantly (P < 0.05). PCA showed that the microflora structure of TC and fecal samples were significantly different between the two groups. Spearman correlation analysis showed that there was no correlation between TC and fecal microorganisms at phyla and genus levels in the same subjects (P > 0.05). The metabolomics results demonstrated that fumarate reductase, V/A ATPase, and phosphatidylethanolamine were increased, and glycerate-3p, UDP-glucose, and quinone oxidoreductase metabolites were decreased in YGTC TC samples. Inosine monophosphate (IMP), uridine monophosphate (UMP), and gamma-aminobutyric acid (GABA) were increased in YGTC fecal samples, while the contents of ribo-5P, histidine, biotin, and cobalamin were decreased. Metabolic pathway analysis indicated that the abundance of the TC and fecal samples of the YGTC subjects was relatively low in various metabolic pathways, including amino acid metabolism, carbohydrate metabolism, nitrogen metabolism, and energy metabolism. ConclusionStructural and functional changes in TC and GIT microbiota or metabolite markers could be potential biological bases of YGTC formation.