Diversity Of Fecal Microbiota Research Articles

Faecalibacterium prausnitzii strain EXL01 boosts efficacy of immune checkpoint inhibitors

ABSTRACT Gut microbiota impacts responses to immune checkpoint inhibitors (ICI). A high level of Faecalibacterium prausnitzii have been associated with a positive response to ICI in multiple cancer types. Here, based on fecal shotgun metagenomics data, we show in two independent cohorts of patients with non-small cell lung cancer and advanced melanoma that a high level of F. prausnitzii at baseline is positively associated with a better clinical response to ICI. In MCA205 tumor-bearing mice, administration of F. prausnitzii strain EXL01, already in clinical development for Inflammatory Bowel Disease, restores the anti-tumor response to ICI in the context of antibiotic-induced microbiota perturbation at clinical and tumor transcriptomics level. In vitro, EXL01 strain enhances T cell activation in the presence of ICI. Interestingly, oral administration of EXL01 strain did not induce any change in fecal microbiota diversity or composition, suggesting a direct effect on immune cells in the small intestine. F. prausnitzii strain EXL01 will be evaluated as an adjuvant to ICI in multiple cancers in the near future.

Investigating the effects of synbiotic supplementation on functional movement, strength and muscle health in older Australians: a study protocol for a double-blind, randomized, placebo-controlled trial

BackgroundAging has been associated with a progressive loss of skeletal muscle quality, quantity and strength, which may result in a condition known as sarcopenia, leading to a decline in physical performance, loss of independence and reduced quality of life. While the cause of impaired physical functioning observed in elderly populations appears to be multifactorial, recent evidence suggests that age-associated alterations in gut microbiota could be a contributing factor. The primary objective will be to assess the effects of a dietary synbiotic formulation on sarcopenia-related functional outcomes such as handgrip strength, gait speed and physical performance within older individuals living independently. The secondary objective will be to examine associations between changes in gut microbiota composition, functional performance and lean muscle mass.MethodsSeventy-four elderly (60–85 years) participants will be randomized in a double-blind, placebo-controlled fashion to either an intervention or control group. The intervention group (n = 37) will receive oral synbiotic formulation daily for 16 weeks. The control group (n = 37) will receive placebo. Assessments of physical performance (including Short Physical Performance Battery, handgrip strength and timed up-and-go tests) and muscle ultrasonography will be performed at 4 time points (baseline and weeks 8, 16 and 20). Likewise, body composition via bioelectric impedance analysis and blood and stool samples will be collected at each time point. Dual-energy X-ray absorptiometry will be performed at baseline and week 16. The primary outcomes will be between-group changes in physical performance from baseline to 16 weeks. Secondary outcomes include changes in body composition, muscle mass and architecture, fecal microbiota composition and diversity, and fecal and plasma metabolomics.DiscussionGut-modulating supplements appear to be effective in modifying gut microbiota composition in healthy older adults. However, it is unclear whether these changes translate into functional and/or health improvements. In the present study, we will investigate the effects of a synbiotic formulation on measures of physical performance, strength and muscle health in healthy older populations.Trial registrationThis study was prospectively registered with the Australian New Zealand Clinical Trials Registry (ACTRN12622000652774) in May 2022.

Associations of Fecal Microbiota with Ectopic Fat in African Caribbean Men.

The gut microbiome has been associated with visceral fat (VAT) in European and Asian populations; however, associations with VAT and with ectopic fats among African-ancestry individuals are not known. Our objective was to investigate cross-sectional associations of fecal microbiota diversity and composition with VAT and ectopic fat, as well as body mass index (BMI), among middle-aged and older African Caribbean men. We included in our analysis n = 193 men (mean age = 62.2 ± 7.6 years; mean BMI = 28.3 ± 4.9 kg/m2) from the Tobago Health Study. We assessed fecal microbiota using V4 16s rRNA gene sequencing. We evaluated multivariable-adjusted associations of microbiota features (alpha diversity, beta diversity, microbiota differential abundance) with BMI and with computed tomography-measured VAT and ectopic fats (pericardial and intermuscular fat; muscle and liver attenuation). Lower alpha diversity was associated with higher VAT and BMI, and somewhat with higher pericardial and liver fat. VAT, BMI, and pericardial fat each explained similar levels of variance in beta diversity. Gram-negative Prevotellaceae and Negativicutes microbiota showed positive associations, while gram-positive Ruminococcaceae microbiota showed inverse associations, with ectopic fats. Fecal microbiota features associated with measures of general adiposity also extend to metabolically pernicious VAT and ectopic fat accumulation in older African-ancestry men.

Microbial Disruptions in Inflammatory Bowel Disease: A Comparative Analysis.

The fecal microbiota was studied in patients with inflammatory bowel disease (IBD), and the characteristics of gut microbiota were compared among patients with different subtypes and stages of IBD, aiming to identify the gut microbiota associated with IBD. Fecal samples were collected from 41 IBD patients (18 patients with ulcerative colitis [UC] and 23 patients with Crohn's disease [CD]) in the Department of Gastroenterology of East China Hospital, Fudan University between January 2021 and January 2022. In addition, fecal samples were collected from 20 healthy volunteers. The fecal microbiota was subjected to 16S rRNA gene sequencing, followed by bioinformatics analysis. There was significant difference in the fecal microbiota between IBD patients and controls. The abundance and diversity of fecal microbiota in the IBD patients were significantly lower than in controls. The relative abundance of Subdoligranulum, Ruminococcus, Anaerostipes and Lachnospira was reduced markedly in the IBD patients. As compared to controls, the relative abundance of Streptococcus increased dramatically in the UC patients. The relative abundance of Lachnoclostridium, Fusobacterium, Cloacibacillus and Erysipelatoclostridium significantly increased in the CD patients. As compared to CD patients, the relative abundance of Alistipes was reduced markedly in the UC patients; the relative abundance of Faecalibacterium, Roseburia and Haemophilus was reduced dramatically in the CD patients. In addition, significant difference was also noted in the fecal microflora between patients with active IBD and those with IBD in remission period. In active IBD patients, the relative abundance of Roseburia, Coprococcus and Ruminiclostridium was reduced significantly. There is intestinal microbiota imbalance in IBD patients, and the abundance of Roseburia, Coprococcus and Ruminiclostridium is reduced significantly in the active period of IBD, which may be related to the active IBD.

Gut microbiota in autoimmune and non-autoimmune liver diseases in children

Relevance. The influence of the gut microbiota on the development of various diseases is of great interest to researchers. The conducted studies showed that in patients with chronic liver diseases, the dominant taxa of the gut microbiota were Bifidobacterium longum, Bifidobacterium adolescentis, Blautia massiliensis, and in healthy children - Neisseria flavescens. There is no comparative analysis of data on the taxonomic diversity of the intestinal microbiota in autoimmune and non-autoimmune liver diseases in children. Purpose of the study. To investigate differences in the taxonomic diversity of fecal microbiota in patients with autoimmune and non-autoimmune liver diseases, as well as to evaluate potential biomarkers of 16S rRNA gene amplicons in these diseases by comparing the taxonomic composition. Scope and methods of research. A metagenomic analysis of the intestinal microbiota of 24 children with chronic liver diseases (mean age 10.3±4.7 years) was carried out with the identification of the V3-V4 region of the 16S rRNA gene. The group included 18 children with autoimmune liver diseases and 6 children with non-autoimmune liver diseases. Research results. The conducted study revealed 684 types of microorganisms in the studied samples of patients’ faeces. The analysis of the conducted studies showed that no dominant taxa were found in the faecal samples of children with autoimmune liver diseases, while Veillonella dispar, Veillonella parvula, Cloacibacillus porcorum, Prevotella histicola and Bacteroides eggerthii were the dominant taxa in patients with non-autoimmune liver diseases. Conclusion. Studies have shown differences in the composition of the gut microbiota in children with autoimmune and non-autoimmune liver diseases.

Comparative assessment of intestinal microbiota in autoimmune and non-autoimmune liver diseases in children

The influence of the gut microbiota on the development of various diseases is of great interest to researchers. The conducted studies showed that in patients with chronic liver diseases, the dominant taxa of the gut microbiota were Bifidobacterium longum, Bifidobacterium adolescentis, Blautia massiliensis, and in healthy children — Neisseria flavescens. There is no comparative analysis of data on the taxonomic diversity of the intestinal microbiota in autoimmune and non-autoimmune liver diseases in children. Purpose. To investigate differences in the taxonomic diversity of fecal microbiota in patients with autoimmune and non-autoimmune liver diseases, as well as to evaluate potential biomarkers of 16S rRNA gene amplicons in these diseases by comparing the taxonomic composition. Material and methods. A metagenomic analysis of the intestinal microbiota of 24 children with chronic liver diseases (mean age 10,3 ± 4,7 years) was carried out with the isolation of the 16S rRNA gene region. The group included 18 children with autoimmune liver diseases and 6 children with non-autoimmune liver diseases. Results. The conducted study revealed 684 types of microorganisms in the studied samples of patients’ feces. The analysis of the conducted studies showed that no dominant taxa were found in the fecal samples of children with autoimmune liver diseases, while Veillonella dispar, Veillonella parvula, Cloacibacillus porcorum, Prevotella histicola and Bacteroides eggerthii were the dominant taxa in patients with non-autoimmune liver diseases. Conclusion. Studies have shown differences in the composition of the gut microbiota in children with autoimmune and non-autoimmune liver diseases.

Fine-scale geographic difference of the endangered Big-headed Turtle (Platysternon megacephalum) fecal microbiota, and comparison with the syntopic Beale’s Eyed Turtle (Sacalia bealei)

BackgroundStudies have elucidated the importance of gut microbiota for an organism, but we are still learning about the important influencing factors. Several factors have been identified in helping shape the microbiome of a host, and in this study we focus on two factors—geography and host. We characterize the fecal microbiota of the Big-headed Turtle (Platysternon megacephalum) and compare across a relatively fine geographic scale (three populations within an 8-km radius) and between two syntopic hosts (P. megacephalum and Sacalia bealei). Both species are endangered, which limits the number of samples we include in the study. Despite this limitation, these data serve as baseline data for healthy, wild fecal microbiotas of two endangered turtle species to aid in conservation management.ResultsFor geography, the beta diversity of fecal microbiota differed between the most distant sites. The genus Citrobacter significantly differs between sites, which may indicate a difference in food availability, environmental microbiota, or both. Also, we identify the common core microbiome for Platysternon across Hong Kong as the shared taxa across the three sites. Additionally, beta diversity differs between host species. Since the two species are from the same site and encounter the same environmental microbiota, we infer that there is a host effect on the fecal microbiota, such as diet or the recruitment of host-adapted bacteria. Lastly, functional analyses found metabolism pathways (KEGG level 1) to be the most common, and pathways (KEGG level 3) to be statistically significant between sites, but statistically indistinguishable between species at the same site.ConclusionsWe find that fecal microbiota can significantly differ at a fine geographic scale and between syntopic hosts. Also, the function of fecal microbiota seems to be strongly affected by geographic site, rather than species. This study characterizes the identity and function of the fecal microbiota of two endangered turtle species, from what is likely their last remaining wild populations. These data of healthy, wild fecal microbiota will serve as a baseline for comparison and contribute to the conservation of these two endangered species.

Differential Microbial Composition and Interkingdom Interactions in the Intestinal Microbiota of Holstein and German Simmental × Holstein Cross F1 Calves: A Comprehensive Analysis of Bacterial and Fungal Diversity.

Calf intestines are colonized by rich and complex microbial communities, playing a crucial role in animal physiology, metabolism, nutrition, and immune function. In this study, we provide insight into the composition of fecal microbial bacteria and fungi, respectively, as well as the cross-kingdom interactions. We investigated the intestinal microbiota of different breeds of calves by characterizing the bacterial and fungal communities in the rectal feces of Holstein calves and German Simmental × Holstein cross F1 generation (GXH) using 16S rRNA and ITS amplicon sequencing techniques. PICRUSt2 (version 2.2.0) were used to determine microbial diversity and function and explore the reasons why Holstein calves are more susceptible to diarrhea. The results revealed no significant difference in the diversity of fecal microbiota among the groups (p > 0.05). We identified Firmicutes, Bacteroidetes, and Proteobacteria as the dominant bacterial phyla in the fecal bacterial communities of the two breeds of calves. Ascomycota and Basidiomycota play important roles in the fungal community but differ in relative abundance. Bacteroides was the dominant genus at the group level for calf fecal microbiota in both breeds. The relative abundance of Prevotella, Escherichia-Shigella, Peptostreptococcus, and Butyricicoccus was higher in Holstein calves, and the relative abundance of Faecalibacterium, Megamonas, Butyricicoccus, and Alloprevotella was lower than GXH group. Aspergillus and Cladosporium were the dominating genera of fecal fungi in both groups of calves. LEfSe analysis revealed 33 different bacteria and 23 different fungi between the two groups, with more differential strains found in GXH. In addition, the feces fungi-bacteria interkingdom interactions varied among breeds. Thus, the composition and structure of bacterial and fungal communities in calf feces varied by breed, indicating a potential association between breed and microbial communities. We also found differences in the network between bacterial-fungal kingdoms. We explain the reasons for Holstein calves being more prone to diarrhea. This indicated that breed makes differences in calf diarrhea rates by influencing gut microbial composition and interactions.

Fecal Microbiota and Feeding Habitats of Nomadic Indigenous Animals (Deer, Yak, Sheep and Camel) in Baikal Siberia (Russia)

In the vast expanse of Baikal Siberia, indigenous nomadic animal groups have been conserved, grazing on pastures throughout the year. It is believed that the fecal microbiota of these diverse nomadic animal species is unique to each species and closely tied to their feeding environments. We conducted a pioneering comparative analysis of the taxonomic structure and the diversity of fecal microbiota in indigenous nomadic animals inhabiting Baikal Siberia. Our study encompassed 20 deer, 23 yaks, 24 camels, and 29 sheep, using high-throughput 16S rRNA gene profiling. In the fecal microbiota of these animals, we observed a predominant presence of the phyla Bacillota, Bacteroidota, and Verrucomicrobiota, collectively comprising over 88% of the microbial communities. Moreover, these proportions exhibited variations according to the host species. The unculturable Bacillota UCG-005 and UCG-010 are the key groups for all animals. However, at the genus level, distinctive compositions of fecal microbiota were discernible within each animal group. We identified a total of 37 dominant genera across the fecal samples from these four animal species. Principal component analysis (PCA) and cluster analysis demonstrated that the fecal microbiota composition clustered among individuals of the same animal species. Linear discriminant analysis effect size (LEfSe) indicated that camels exhibited higher abundances of the family Akkermansiaceae and the uncultured clostridial lineage UCG-010, while deer featured Lachnospiraceae; sheep had Ruminococcaceae; and yaks displayed Monoglobaceae, Bacteroidaceae, and methanogenic archaea from the family Methanobacteriaceae as distinctive marker taxa. Our studies showed that the studied nomadic animals feed mainly on plants belonging to the families Poaceae, Cyperaceae, Asteraceae, and Rosaceae. Our research indicated that the identity of the host species and, to a lesser degree, their diets and habitats, significantly shape the composition of fecal microbiota in these studied nomadic ruminant animals.

Gut microbiota and metabolic profiles in chronic intermittent hypoxia-induced rats: disease-associated dysbiosis and metabolic disturbances.

Chronic intermittent hypoxia (CIH) is a key characteristic of obstructive sleep apnea (OSA) syndrome, a chronic respiratory disorder. The mechanisms of CIH-induced metabolic disturbance and histopathological damage remain unclear. CIH-induced rats underwent daily 8-h CIH, characterized by oxygen levels decreasing from 21% to 8.5% over 4min, remaining for 2min, and quickly returning to 21% for 1min. The control rats received a continuous 21% oxygen supply. The levels of hypersensitive C reactive protein (h-CRP), tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), interleukin 8 (IL-8), and nuclear factor kappa-B (NF-κB) were measured by ELISA. Histological analysis of the soft palates was conducted using HE staining. The microbial profiling of fecal samples was carried out by Accu16STM assay. Untargeted metabolomics of serum and soft palate tissue samples were analyzed by UPLC-MS. The protein expression of cAMP-related pathways in the soft palate was determined by Western blot. After 28h of CIH induction, a significant increase in pro-inflammatory cytokines was observed in the serum, along with mucosal layer thickening and soft palate tissue hypertrophy. CIH induction altered the diversity and composition of fecal microbiota, specifically reducing beneficial bacteria while increasing harmful bacteria/opportunistic pathogens. Notably, CIH induction led to a significant enrichment of genera such as Dorea, Oscillibacter, Enteractinococcus, Paenibacillus, Globicatella, and Flaviflexus genera. Meanwhile, Additionally, CIH induction had a notable impact on 108 serum marker metabolites. These marker metabolites, primarily involving amino acids, organic acids, and a limited number of flavonoids or sterols, were associated with protein transport, digestion and absorption, amino acid synthesis and metabolism, as well as cancer development. Furthermore, these differential serum metabolites significantly affected 175 differential metabolites in soft palate tissue, mainly related to cancer development, signaling pathways, amino acid metabolism, nucleotide precursor or intermediate metabolism, respiratory processes, and disease. Importantly, CIH induction could significantly affect the expression of the cAMP pathway in soft palate tissue. Our findings suggest that targeting differential metabolites in serum and soft palate tissue may represent a new approach to clinical intervention and treatment of OSA simulated by the CIH.

Green banana flour as a novel functional ingredient in retorted feline diets.

Green banana flour (GBF) is a novel ingredient that is high in resistant starch and could be a dietary fiber source in companion animal nutrition. In addition, with its light brown color and pectin content, GBF could potentially serve as a natural color additive and thickening agent in pet food manufacturing. The purpose of this research is to evaluate different sources of GBF, the effect of GBF on texture and color in canned foods, and its effect on apparent total tract digestibility (ATTD), fecal characteristics, and fecal fermentative end-products in healthy adult cats. Prior to the feline study, different sources of GBF were analyzed for chemical composition, manufacturing properties, true metabolizable energy, and fermentability. For the feline feeding trial, all treatment diets were formulated to meet or exceed the Association of American Feed Control Officials (Association of American Feed Control Officials (AAFCO) 2020. Official Publication. Champaign, IL.) guidelines for adult cat maintenance. There were five dietary treatments: rice control (4% rice flour), potato control (4% dehydrated potato flakes), 1% GBF (1% GBF and 3% rice flour), 2% GBF (2% GBF and 2% rice flour), and 4% GBF. All treatment diets were analyzed for texture and color. The animal study was conducted using a completely randomized design with 39 adult domestic cats. There was a 7-d diet adaptation period followed by a baseline fresh fecal collection to determine fecal score, pH, short-chain fatty acid, branched-chain fatty acid, phenol, indole, ammonia, and microbiota. The treatment period lasted for 21 d and a total fecal collection was performed during the last 4 d of this period to determine the ATTD. A fresh fecal sample was also collected during the total fecal collection to evaluate fecal score, pH, metabolites, and microbiota. The MIXED model procedures of SAS version 9.4 were used for statistical analysis. Treatment diets containing GBF had a lower hardness from the texture profile analysis (P < 0.05). For color analysis, the 4% GBF diet was darker in color compared with the rice diet (P < 0.05). There was no difference in food intake, fecal output, or ATTD of macronutrients among the treatment groups (P > 0.05). There was no interaction of treatment and time or main effects shown in fecal score, pH, metabolites, or microbiota diversity (P > 0.05). In conclusion, adding GBF to canned diets may affect the texture and color of the product, but GBF was comparable to traditional carbohydrate sources, rice, and potato, from a nutritional aspect.

The effects of hydrolyzed protein on macronutrient digestibility, fecal metabolites and microbiota, oxidative stress and inflammatory biomarkers, and skin and coat quality in adult dogs.

Research on protein hydrolysates has observed various properties and functionalities on ingredients depending on the type of hydrolysate. The objective of this study was to evaluate the effects of hydrolyzed chicken protein that was incorporated into diets on digestibility, gut health, skin and coat health, oxidative stress, and intestinal inflammation markers in healthy adult dogs. Five complete and balanced diets were manufactured: (1) CONd: 25% chicken meal diet; (2) 5% CLHd: 5% chicken liver and heart hydrolysate plus 20% chicken meal diet; (3) CLHd: 25% chicken liver and heart hydrolysate diet; (4) 5% CHd: 5% chicken hydrolysate plus 20% chicken meal diet; (5) CHd: 25% chicken hydrolysate diet. A replicated 5 × 5 Latin square design was used which included 10 neutered adult Beagles. Each of the 5 periods consisted of a 7-d washout time and a 28-d treatment period. All diets were well accepted by the dogs. Fecal butyrate concentration was higher while fecal isovalerate and total phenol/indole were lower in dogs fed CLHd than CONd (P < 0.05). Dogs fed CHd had higher fecal immunoglobulin A concentration when compared with CLHd (P < 0.05); however, both groups were comparable to the CONd. There was no difference among groups in serum cytokine concentrations, serum oxidative stress biomarkers, or skin and coat health analyses (P > 0.05). Fecal microbiota was shifted by CLHd with higher abundance in Ruminococcus gauvreauii group as well as lower Clostridium sensu stricto 1, Sutterella, Fusobacterium, and Bacteroides when compared with CONd (P < 0.05). There was also a difference in beta diversity of fecal microbiota between CLHd and CHd (P < 0.05). In conclusion, chicken protein hydrolysate could be incorporated into canine extruded diets as a comparable source of protein to traditional chicken meal. The test chicken protein hydrolysates showed the potential to support gut health by modulating immune response and microbiota; however, functional properties of protein hydrolysates are dependent on inclusion level and source.

Faecal microbiota and fatty acids in feline chronic enteropathy

BackgroundFeline chronic enteropathy is a set of disorders defined as the presence of clinical signs of gastrointestinal disease for at least three weeks. The most common final diagnoses are inflammatory bowel disease and alimentary small cell lymphoma. The etiopathogenesis of these diseases is incompletely understood; however, it is hypothesised that they involve a combination of factors, including altered composition and/or functionality of the intestinal microbiome. An important factor in the interplay of the microbiome and host is the production of short- and branched-chain fatty acids. The aim of this study was to evaluate the possible differences in faecal microbiota diversity, composition and fatty acid production between cats suffering from chronic enteropathy and healthy cats. Sixteen cats suffering from chronic enteropathy and fourteen healthy control cats were enrolled in the study. The microbiota compositions of faecal samples were analysed by using next-generation amplicon sequencing of the V3V4 fragment of the 16S rRNA gene. Fatty acids were evaluated by high-performance liquid chromatography.ResultsBoth the alpha and beta diversities were significantly lower in samples obtained from cats with chronic enteropathy. The relative abundance of the phylum Proteobacteria, orders Lactobacillales and Enterobacterales, family Enteriobacteriaceae and genus Escherichia Shigella were higher in diseased cats, whereas the abundance of the phylum Bacteroidota and order Peptococcales were higher in control cats. The faecal concentrations of short-chain fatty acids were higher in cats with chronic enteropathy, with lower propionate proportions and higher butyrate proportions.ConclusionThe study revealed alterations in microbiota compositions and short-chain fatty acid concentration in cats suffering from chronic enteropathy, which is an important finding both for research on the pathogenesis of the disease and for potential therapeutic interventions in the form of faecal microbiota transplantation and/or probiotic supplementation.

Comparative evaluation of the fecal microbiota of adult hybrid pigs and Tibetan pigs, and dynamic changes in the fecal microbiota of hybrid pigs.

The breed of pig can affect the diversity and composition of fecal microbiota, but there is a lack of research on the fecal microbiota of hybrid pigs. In this study, feces samples from Chuanxiang black pigs (a hybrid of Tibetan and Duroc pigs) aged 3 days (n = 24), 70 days (n = 31), 10 months (n = 13) and 2 years (n = 30) and Tibetan pigs aged 10 months (n = 14) and 2 years (n = 15) were collected and sequenced by 16S rRNA gene sequencing technology. We also measured the weight of all the tested pigs and found that the 10-month-old and two-year-old Chuanxiang black pigs weighed about three times the weight of Tibetan pigs of the same age. After comparing the genus-level microbiota composition of Tibetan pigs and Chuanxiang black pigs at 10 months and two years of age, we found that Treponema and Streptococcus were the two most abundant bacteria in Chuanxiang black pigs, while Treponema and Chirstensenellaceae_R.7_group were the two most abundant bacteria in Tibetan pigs. Prediction of microbial community function in adult Chuanxiang black pigs and Tibetan pigs showed changes in nutrient absorption, disease resistance, and coarse feeding tolerance. In addition, we also studied the changes in fecal microbiota in Chuanxiang black pigs at 3 days, 70 days, 10 months, and 2 years of age. We found that the ecologically dominant bacteria in fecal microbiota of Chuanxiang black pigs changed across developmental stages. For example, the highest relative abundance of 70-day-old Chuanxiang black pigs at the genus level was Prevotella. We identified specific microbiota with high abundance at different ages for Chuanxiang black pigs, and revealed that the potential functions of these specific microbiota were related to the dominant phenotype such as fast growth rate and strong disease resistance. Our findings help to expand the understanding of the fecal microbiota of hybrid pigs and provide a reference for future breeding and management of hybrid pigs.

Associations of Plastic Bottle Exposure with Infant Growth, Fecal Microbiota, and Short-Chain Fatty Acids.

Murine models show that plastics, via their chemical constituents (e.g., phthalates), influence microbiota, metabolism, and growth. However, research on plastics in humans is lacking. Here, we examine how the frequency of plastic bottle exposure is associated with fecal microbiota, short-chain fatty acids (SCFAs), and anthropometry in the first year of life. In 442 infants from the prospective Nurture birth cohort, we examined the association of frequency of plastic bottle feeding at 3 months with anthropometric outcomes (skinfolds, length-for-age, and weight-for-length) at 12 months of age and growth trajectories between 3 and 12 months. Furthermore, in a subset of infants (n = 70) that contributed fecal samples at 3 months and 12 months of age, we examined plastic bottle frequency in relation to fecal microbiota composition and diversity (measured by 16S rRNA gene sequencing of V4 region), and fecal SCFA concentrations (quantified using gas chromatography mass spectrometry). At 3 months, 67.6% of infants were plastic bottle fed at every feeding, 15.4% were exclusively breast milk fed, and 48.9% were exclusively formula fed. After adjustment for potential confounders, infants who were plastic bottle fed less than every feeding compared to those who were plastic bottle fed at every feeding at 3 months did not show differences in anthropometry over the first 12 months of life, save for lower length-for-age z-score at 12 months (adjusted β = -0.45, 95% CI: -0.76, -0.13). Infants who were plastic bottle fed less than every feeding versus every feeding had lower fecal microbiota alpha diversity at 3 months (mean difference for Shannon index: -0.59, 95% CI: -0.99, -0.20) and lower isovaleric acid concentration at 3 months (mean difference: -2.12 μmol/g, 95% CI: -3.64, -0.60), but these results were attenuated following adjustment for infant diet. Plastic bottle frequency was not strongly associated with microbiota diversity or SCFAs at 12 months after multivariable adjustment. Frequency of plastic bottle use was associated with differential abundance of some bacterial taxa, however, significance was not consistent between statistical approaches. Plastic bottle frequency at 3 months was not strongly associated with measures of adiposity or growth (save for length-for-age) over the first year of life, and while plastic bottle use was associated with some features of fecal microbiota and SCFAs in the first year, these findings were attenuated in multivariable models with infant diet. Future research is needed to assess health effects of exposure to other plastic-based products and objective measures of microplastics and plastic constituents like phthalates.

Effect of Miscellaneous Meal Replacements for Soybean Meal on Growth Performance, Serum Biochemical Parameters, and Gut Microbiota of 50-75 kg Growing Pigs.

This study was carried out to investigate the effects of miscellaneous meal (rapeseed meal, cottonseed meal, and sunflower seed meal) as a replacement for soybean meal on growth performance, apparent nutrient digestibility, serum biochemical parameters, serum free amino acid contents, and gut microbiota of 50-75 kg growing pigs. A total of 54 healthy growing pigs (Duroc × Landrace × Yorkshire) with initial body weights (BWs) of 50.64 ± 2.09 kg were randomly divided into three treatment groups, which included the corn-soybean meal group (CON), corn-soybean-miscellaneous meal group (CSM), and corn-miscellaneous meal group (CM). Each treatment included six replicates with three pigs in each replicate. Dietary protein levels were maintained at 15% in all three treatment groups. Additional rapeseed meals, cottonseed meals, and sunflower seed meals were added to the CSM group's meals to partially replace the 10.99% soybean meal in the CON group in a 1:1:1 ratio. Pigs in the CM group were fed a diet with a mixture of miscellaneous meals (7.69% rapeseed meal, 7.69% cottonseed meal, and 7.68% sunflower seed meal) to totally replace soybean meal. Our findings revealed that there was no significant impact of replacing soybean meal with miscellaneous meal on the ADG (average daily gain), ADFI (average daily feed intake), or F/G (feed-to-gain ratio) (p > 0.05) of growing pigs weighing 50-75 kg, nor on the crude protein, crude fat, or gross energy (p > 0.05) of the diet. On the other hand, compared to the CON group, the CM group exhibited significantly elevated serum alanine aminotransferase (ALT) and triglyceride (TG) levels (p < 0.05), while urea levels were significantly reduced (p < 0.05). No significant effect was observed on the serum free amino acid contents (p > 0.05) following the substitution of soybean meal with miscellaneous meal. A t-test analysis indicated that compared with the CON group, the CM group exhibited a significantly diminished abundance of Euryachaeota at the phylum level and augmented abundance of Desulfobacterota at the genus level. This study demonstrated that the miscellaneous meals (rapeseed meal, cottonseed meal, and sunflower seed meal) as a substitute for soybean meal in the diet had no significant negative effects on the growth performance, apparent nutrient digestibility, serum amino acid content, or diversity of fecal microbiota in 50-75 kg growing pigs. These results can be helpful in developing further miscellaneous meals (rapeseed meal, cottonseed meal, and sunflower seed meal) as functional alternative feed ingredients to soybean meal in pig diets.

PSIX-2 Effects of Diets Supplemented with Bioactive Peptides on Nutrient Digestibility, Immune Cell Responsiveness, and Fecal Characteristics, Microbiota, and Metabolites of Adult Cats

Abstract Bioactive peptides (BP) are recognized for their ability to function as antioxidants and maintain lipid stability. They may have positive health effects, including antihypertensive, anti-inflammatory, antimicrobial, osteoprotective, gut health and immunomodulatory properties. Our objective was to determine the apparent total tract digestibility (ATTD) of bioactive peptide-containing kibble diets and assess how the fecal characteristics, metabolites, and microbiota were affected in adult cats. All procedures were approved by the University of Illinois IACUC. Twelve adult cats (4-5 yr; 4.84 kg avg. BW) were used in a replicated 4x4 Latin square design (n = 12/group) and fed to maintain BW. In each experimental period, cats were allotted to one of four extruded kibble experimental diets: control (4% dried chicken), chicken (4% chicken BP), marine1 (2% marine BP), and marine2 (4% marine BP). Health was confirmed by baseline serum chemistry and complete blood count analysis. Each experimental period lasted 28 days, with a 20-day adaptation phase, 5-day fecal collection [for nutrient digestibility, microbiota, metabolites, IgA, calprotectin, lactoferrin, pH, and dry matter (DM) analysis], 2-day blood collection (for serum chemistry, complete blood count, and immune cell functionality analysis), and 1 day for transport stress testing. For transport stress, cats were transported in a vehicle in individual carriers for 45 minutes. Upon return, their behavior was evaluated using the cat stress score (CSS). Saliva samples were collected within 15 minutes to measure cortisol concentrations and blood samples were collected after 3 hours to measure concentrations of oxidative stress markers [superoxide dismutase (SOD) and malondialdehyde (MDA)] and inflammatory cytokines. Fecal microbiota data were evaluated using QIIME2. All other data were analyzed using the Mixed Models procedure of SAS, with P &amp;lt; 0.05 being considered significant. No significant differences were observed in animal health outcomes, with all cats remaining healthy within reference ranges. There were no differences in fecal characteristics, metabolites, and microbiota diversity. Cats fed the marine2 diet had a 3.61% greater (P &amp;lt; 0.05) ATTD of DM and a 2.5% greater organic matter digestibility than those fed the control diet. The relative abundance of fecal Blautia was greater (P &amp;lt; 0.05) in cats fed the control diet than those fed the chicken diet, while relative abundance of fecal Slackia was greater (P &amp;lt; 0.05) in cats fed the control diet than those fed the chicken or marine1 diets. In comparison with cats fed the marine1 diet, the relative abundances of fecal Sellimonas and Bifidobacterium were less (P &amp;lt; 0.05) in cats fed the control diet. Neither transport stress nor diet impacted the oxidative stress markers, cytokines, cortisol, or CSS. Furthermore, the diet did not affect immune cell functionality. In conclusion, including BP, in particular marine2 at 4% inclusion to feline diets may increase nutrient digestibility and modify fecal microbiota.

196 The Effect of Hydrolyzed Protein on Fecal Microbiota in Adult Dogs

Abstract Research on protein hydrolysates has observed various properties and functionalities of these ingredients depending on the type of hydrolysate. The objective of this study was to evaluate the effect of hydrolyzed chicken protein that was incorporated into diets on gut health in healthy adult dogs. Five complete and balanced treatment diets were manufactured: 1) CONd: chicken meal diet; 2) 5% CLHd: 5% substitution of chicken liver hydrolysate of chicken meal diet; 3) CLHd: chicken liver hydrolysate diet; 4) 5% CHd: 5% substitution of chicken hydrolysate of chicken meal diet; and 5) CHd: chicken hydrolysate diet. A 5×5 Latin square design was used which included 10 neutered adult beagles. Each of the 5 periods consisted of a 7-d washout time and a 28-d treatment period. All diets were well accepted by the dogs. For fecal metabolites, there was greater fecal butyrate concentration as well as reduced isovalerate, 4-ethylphenol, and indole in dogs fed CLHd than CONd (P &amp;lt; 0.05). Regarding the overall microbiota composition, Firmicutes, Bacteriodota, Fusobacteriota, Actinobacteriota, and Proteobacteria were the top 5 most abundant phyla. At the class level, samples from CHd group had greater relative abundances of Bacteriodia and Fusobacteriia as well as less Bacilli. On the other hand, CLHd group had greater abundances of Bacilli and Actinobacteria with less Fusobacteriia. At the level of order, CHd group had greater Bacteriodales and Fusobacteriales while CLHd group had greater Bifidobacteriales. At the family level, CHd group showed a greater abundance of Muribaculaceae and a decreased abundance of Bifidobacteriaceae when compared with the other groups. Alternatively, CLHd group demonstrated a greater abundance of Bifidobacteriaceae together with reduced abundance of Fusobacteriaceae, Muribaculaceae, Sutterrellaceae, and Ruminococcaceae. Fecal microbiota was shifted by CLHd with greater differential abundance in Ruminococcus gauvreauii group as well as reduced Clostridium sensu stricto 1, Sutterella, Fusobacterium, and Bacteroides compared with CONd (P &amp;lt; 0.05). There was also a difference in beta diversity of fecal microbiota between CLHd and CHd (P &amp;lt; 0.05). However, no difference was observed in alpha diversity among treatment groups (P &amp;lt; 0.05). Fecal butyrate concentration was negatively correlated with the genera Blautia, Phascolarctobacterium, Sutterella, Faecalibacterium, and Bacteriodes. Conversely, Allobaculum and Bifidobacterium were positively correlated with butyrate concentration. In conclusion, the test chicken protein hydrolysates may have potential to support gut health by modulating microbiota.

The Correlation between Alterations in the Intestinal Microbiome and Early Outcomes of Autologous Hematopoietic Cell Transplantation in Diffuse Large B-Cell Lymphoma

Introduction: Prior research has documented a decline in the diversity of fecal microbiota among individuals with diffuse large B-cell lymphoma (DLBCL) who undergo autologous hematopoietic cell transplantation (auto-HCT). Nevertheless, the potential influence of gut microbiota on hematopoietic reconstitution, immune reconstitution, and early complications in this specific patient cohort remains uncertain. Methods: A total of 42 fecal samples were obtained from 21 adult individuals who underwent autologous hematopoietic cell transplantation (auto-HCT) for diffuse large B-cell lymphoma (DLBCL), both prior to and two weeks following allogeneic stem cell transplantation (ASCT). The diversity of fecal microbiota was assessed using 16S ribosomal gene sequencing. Additionally, correlations between alterations in the fecal microbiome and clinical characteristics, as well as host immune indices, were examined. Results: The beta diversity index of intestinal microecology exhibited a significant decrease following transplantation, whereas the alpha diversity index remained unaltered. Prior to transplantation, the abundance of g_Prevotella_7, g_Sutterella, and g_Enterococcus demonstrated a positive correlation with intestinal infection caused by Carbapenem-resistant Enterobacteriaceae. Conversely, the abundance of g_Blautia prior to transplantation and g_Lachnospira following transplantation exhibited a negative correlation with the duration of post-transplant fever. The abundance of g_Enterocococcus, g_Veillonella, g_Sutterella, g_Prevotella_7, and g_Streptococcus following transplantation exhibited a positive correlation with the occurrence of diarrhea. Conversely, the abundance of g_Weissella displayed a negative correlation with the duration of neutrophil and megakaryocyte engraftment, while g_Prevotella_7 exhibited a positive correlation with the duration of neutrophil engraftment. Additionally, the abundance of g_Sutterella and g_Prevotella_7 prior to transplantation, as well as the abundance of g_Lachnoclostridium, g_Blautia, g_Lachnospira, g_Veillonella, and g_Sutterella following transplantation, were positively correlated with host immunity. Conclusions: The intestinal microbiome experienced significant fluctuations throughout the autologous stem cell transplantation (ASCT) procedure in patients with diffuse large B-cell lymphoma (DLBCL), and these changes exhibited a strong correlation with both early prognosis and post-transplant immune reconstitution. Consequently, additional investigation is necessary to establish strategies for modulating the gut microbiota and enhancing the efficacy of ASCT in DLBCL patients.

Shotgun Sequencing of Multi-Site Oral and Colonic Microbiota in Patients with AML: Site-Specific Patterns and Microbiota Decompartmentalization

Gut microbiota is a source of pathogens in immunocompromised patients. While most microbiota studies in patients with AML receiving induction chemotherapy have focused on the gut microbiota, the few on salivary microbiota suggest less severe dysbiosis. As the saliva does not have its own intrinsic microbiota and takes fractions of the microbiota from the different oral tissues it bathes, the extent to which the salivary microbiota reflects microbial changes in other oral sites is unknown. To fill this knowledge gap, we characterized the microbiota in longitudinal salivary, supragingival plaque, and fecal samples of AML patients receiving inpatient chemotherapy. 31 patients have been enrolled in this prospective single-center study. Baseline stool, saliva, and plaque samples were collected at baseline and repeated weekly until 5 weeks after starting chemotherapy or discharge from the hospital, whichever occurred first. Time was divided into 3 intervals: admission to day 10 of chemotherapy, days 11-20, and day 21 and later. 111 samples (stool: 39, saliva: 36, plaque: 36) from 16 patients have been sequenced to date. Samples underwent shotgun sequencing targeting 10M paired-end reads/sample. MetaPhlAn4 was used for taxonomic assignment. Alpha diversity was quantified by Shannon index and beta diversity by Bray-Curtis dissimilarity. 9 patients were male and 7 were female. Median age was 64 (range 34-82). 15 patients were newly diagnosed and 1 was relapsed/refractory. Chemotherapy regimens included CLAG-M (n=10), ATRA+ATO (n=3), Vyxeos (n=1), Venetoclax+Azacitidine (n=1), and intermediate-dose Ara-C (n=1). The 3 most frequently used antibacterial antibiotics were cefepime (n=14), IV vancomycin (n=12), and levofloxacin (n=11). Median hospitalization length was 19 days (range 6-31). Neutropenic fever occurred in 13 patients. Documented infections included bacteremia (n=8), skin/soft tissue (n=5), intestinal (n=4), urinary tract (n=4), and pneumonia (n=1). Four bacterial species isolated from blood cultures of patients with fever were detected by sequencing 1-2 weeks before bacteremia: Gemella Haemolysans in saliva, plaque, and stool, Streptococcus mitis in saliva and stool, Rothia mucilaginosa in saliva and plaque, and Citrobacter freundii in stool. Microbiota diversity from the 3 sites showed markedly different dynamics ( Fig. 1). Plaque microbiota diversity remained stable throughout, with levels as high as fecal microbiota in intervals 1 and 2, and higher than both fecal and salivary microbiota in interval 3. Salivary microbiota diversity was the lowest among sites in intervals 1 and 2 and experienced only a slight reduction in interval 3. In contrast, fecal microbiota diversity was high compared to the other sites in intervals 1 and 2 but dropped in interval 3 to the lowest among all sites. With all 3 intervals combined, salivary microbiota had lower diversity (median 1.9, range 0.04-3.9) than plaque (median 2.7, 0.2-4.3; P=0.01) and fecal microbiota (median 2.9, 0.3-3.7; P=0.048). The 3 sites largely segregated on hierarchical clustering using species abundances ( Fig. 2). However, microbiota in several low-diversity samples from different sites in the same patient coalesced: Veillonella parvula and R. mucilaginosa were detected in all 3 sites, V. dispar in stool and plaque, and S. parasanguinis in stool and saliva. Each overlap was present in 5 or more patients. This first shotgun sequencing analysis of longitudinal salivary, plaque, and fecal microbiota in AML patients offers several novel findings. First, plaque microbiota diversity is stable despite exposure to antibiotics, whereas fecal microbiota diversity is not. Second, while healthy adults show no overlap between oral and colonic microbiota, low-diversity fecal samples from AML patients contained species of their own oral microbiota, particularly at later time points. These data suggest ectopic colonization of the gut by oral flora. Future mechanistic studies of plaque biofilms may reveal community-protective mechanisms that sustain oral plaque microbial diversity and contribute oral flora to the gut. Mitigating gut dysbiosis in AML patients by manipulating plaque biofilms could be a novel approach to improve patient outcomes.