Fecal Concentrations Research Articles

Increase in bile acids after sleeve gastrectomy improves metabolism by activating GPBAR1 to increase cAMP in mice with nonalcoholic fatty liver disease.

Bile acids (BAs) concentration can affect metabolic improvement caused by bariatric surgery and BA concentrations increase in patients after sleeve gastrectomy (SG). Here, how BAs after SG affect metabolism in nonalcoholic fatty liver disease (NAFLD) was studied. Mice were given high-fat diet (HFD) to induce NAFLD and received SG surgery. Hepatic and fecal BA concentrations in mice were detected by liquid chromatography-tandem mass spectrometry method. BA-related genes were detected by quantitative real-time polymerase chain reaction. G protein BA receptor 1 (GPBAR1) expression was identified using western blot analysis. NAFLD mice after SG received GPBAR1 inhibitor Triamterene. The weight of mice and mice liver was detected. Mouse liver tissue was observed by hematoxylin-eosin and Oil Red O staining. Triglyceride (TG), nonesterified fatty acid (NEFA), and cyclic adenosine monophosphate (cAMP) levels in mouse liver tissue were analyzed by metabolic assay and enzyme-linked immune sorbent assay. SG boosted increase in hepatic total/conjugated BAs and related genes and GPBAR1 expression, and attenuated increase in fecal total BAs/muricholic acid in HFD-induced mice and increased fecal taurine-BAs in HFD-induced mice. Triamterene (72 mg/kg) reversed the inhibitory role of SG in HFD-induced increase of body weight, lipid accumulation, inflammatory cell infiltration, and increase of hepatic weight and TG/NEFA content, and counteracted the positive role of SG in HFD-induced increase of hepatic cAMP concentration in mice. BAs improve metabolism via activating GPBAR1 to increase cAMP in NAFLD mice after SG.

The impact of primary-care led, faecal immunochemical test-based, triage of new-onset colorectal symptoms on time to diagnosis of colorectal cancer-An observational study.

Since December 2015, a faecal immunochemical test (FIT) has been provided to primary care in NHS Tayside as an adjunct to clinical acumen in the assessment of new-onset bowel symptoms. The aim of this work was to assess the impact of this approach on time to diagnosis of colorectal cancer (CRC). NHS Tayside Cancer audit data from January 2013 to December 2019 were reviewed to identify all CRC patients diagnosed via the primary-care referral pathway for a period before and after the introduction of FIT. Their electronic patient records were accessed and date of referral and any contemporaneous FIT and full blood count (FBC) result were recorded. Time from referral to diagnosis of CRC was calculated for each patient and compared between subgroups. The study cohort consisted of 959 patients: 378 and 581 from the time periods before and after the introduction of FIT, respectively. The median time to diagnosis before FIT was 30 days [interquartile range (IQR) 16-57 days] versus 25 days (IQR 14-47 days) following the introduction of FIT (p = 0.006). Following the introduction of FIT, patients who completed a FIT had a median of time to diagnosis of 23 days (IQR 14-43 days) compared with 30 days (IQR 16-62 days) for patients not completing a FIT (p = 0.019). FBC results were available for 97.5% of FIT patients to aid safety-netting of patients with a low or undetectable faecal haemoglobin concentration. The introduction of FIT-based triage of new bowel symptoms in primary care as an adjunct to clinical acumen is associated with a reduced time to CRC diagnosis.

Sex-specific effects of gut microbiome on shaping bile acid metabolism.

Gut microbiome is a group of microorganisms that plays important roles in contributing to health and diseases. These bacterial compositions have been demonstrated to impact bile acids (BAs) profiles, either by directly metabolizing primary BAs to secondary BAs or indirect ways through host metabolism by influencing BAs synthesis, transportation and conjugation in liver. It has been observed sexually dimorphic gut microbiome and bile acids composition, with variations in expression levels of bile acid metabolizing genes in the liver. However, associations between sex-specific differences in gut microbiome and BAs profiles are not well understood. This study aimed to investigate whether gut microbiome could influence BAs profiles in host in a sexspecific manner. We transplanted cecum feces of male and female C57BL/6 mice to male mice and measured BAs concentrations in feces, serum and liver samples 7 days after fecal transplantation. We found different BAs profiles between mice with male and female gut microbiome, including altering levels and proportions of secondary BAs. We also observed varied expression levels of genes related to bile acid metabolism in the liver and distal ileum. Our results highlight sex-specific effects of gut microbiome on shaping bile acid metabolism through gut bacteria and regulation of host genes.

Intermittent fasting and high-intensity interval training do not alter gut microbiota composition in adult women with obesity.

Obesity is advancing at an accelerated pace, and yet its treatment is still an emerging field. Although studies have demonstrated the role of the microbiota in the pathogenesis of obesity, this is the first study to show the effects of intermittent fasting (IF), combined or not with exercise, and high-intensity interval training (HIIT) on the gut microbiota composition in women with obesity. Our hypothesis is that IF combined with HIIT can promote the remodeling of the composition and function of the gut microbiota. Thirty-six women with obesity, aged between 18 and 40 yr, participated in the study. They were randomly divided into three groups: 1) IF associated with HIIT group [IF + exercise group (EX), n = 15]; 2) HIIT group (EX, n = 11); and 3) IF group (IF, n = 10). Interventions took place over 8 wk, and all assessments were performed preintervention and postintervention. The HIIT circuit was performed 3 times/wk, for 25 min/session. The IF protocol was a 5:2 (2 times/wk). Multiplex analysis of inflammatory cytokines, sequencing of the 16S rRNA gene, and gas chromatography to measure fecal concentrations of short-chain fatty acids (SCFAs) were performed. This study was registered on ClinicalTrials.gov (NCT05237154). Exercise increased fecal acetate concentrations (P = 0.04), but no changes were observed in the composition and functional profile of the microbiota. The interventions did not change the composition of the microbiota, but exercise may play a modulatory role in the production of acetate. This investigation provides clinical insights into the use of IF and HIIT for women with obesity.NEW & NOTEWORTHY This is the first investigation about alternate-day fasting combined with HITT on the gut microbiota of obese women. The study contributes to the advancement of human science involving IF and HIIT, popular strategies for managing obesity. Previous evidence has explored IF in modulating the microbiota in animal models or specific populations and clinical conditions. Despite the subtle outcomes, this study has relevance and originality in the field of gut microbiota knowledge.

Gut microbiome signatures associated with type 2 diabetes in obesity in Mongolia.

Mongolian people possess a unique dietary habit characterized by high consumption of meat and dairy products and fewer vegetables, resulting in the highest obesity rate in East Asia. Although obesity is a known cause of type 2 diabetes (T2D), the T2D rate is moderate in this population; this is known as the "Mongolian paradox." Since the gut microbiota plays a key role in energy and metabolic homeostasis as an interface between food and body, we investigated gut microbial factors involved in the prevention of the co-occurrence of T2D with obesity in Mongolians. We compared the gut microbiome and metabolome of Mongolian adults with obesity with T2D (DO: n = 31) or without T2D (NDO: n = 35). Dysbiotic signatures were found in the gut microbiome of the DO group; lower levels of Faecalibacterium and Anaerostipes which are known as short-chain fatty acid (SCFA) producers and higher levels of Methanobrevibacter, Desulfovibrio, and Solobacterium which are known to be associated with certain diseases. On the other hand, the NDO group exhibited a higher level of fecal SCFA concentration, particularly acetate. This is consistent with the results of the whole shotgun metagenomic analysis, which revealed a higher relative abundance of SCFA biosynthesis-related genes encoded largely by Anaerostipes hadrus in the NDO group. Multiple logistic regression analysis including host demographic parameters indicated that acetate had the highest negative contribution to the onset of T2D. These findings suggest that SCFAs produced by the gut microbial community participate in preventing the development of T2D in obesity in Mongolians.

Non-invasive biomonitoring of polar bear feces can be used to estimate concentrations of metals of concern in traditional food.

The Arctic faces increasing exposure to environmental chemicals such as metals, posing health risks to humans and wildlife. Biomonitoring of polar bears (Ursus maritimus) can be used to quantify chemicals in the environment and in traditional foods consumed by the Inuit. However, typically, these samples are collected through invasive or terminal methods. The biomonitoring of feces could be a useful alternative to the current metal monitoring method within the Arctic. Here, we aim to 1) quantify the relationship between concentrations of metals in the feces and tissues (muscle, liver, and fat) of polar bears using predictive modeling, 2) develop an easy-to-use conversion tool for use in community-based monitoring programs to non-invasively estimate contaminant concentrations in polar bears tissues and 3) demonstrate the application of these models by examining potential exposure risk for humans from consumption of polar bear muscle. Fecal, muscle, liver, and fat samples were harvested from 49 polar bears through a community-based monitoring program. The samples were analyzed for 32 metals. Exploratory analysis indicated that mean metal concentrations generally did not vary by age or sex, and many of the metals measured in feces were positively correlated with the internal tissue concentration. We developed predictive linear regression models between internal (muscle, liver, fat) and external (feces) metal concentrations and further explored the mercury and methylmercury relationships for utility risk screening. Using the cross-validated regression coefficients, we developed a conversion tool that contributes to the One Health approach by understanding the interrelated health of humans, wildlife, and the environment in the Arctic. The findings support using feces as a biomonitoring tool for assessing contaminants in polar bears. Further research is needed to validate the developed models for other regions in the Arctic and assess the impact of environmental weathering on fecal metal concentrations.

Gut microbial features and dietary fiber intake predict gut microbiota response to resistant starch supplementation

ABSTRACT Resistant starch (RS) consumption can have beneficial effects on metabolic health, but the response, in terms of effects on the gut microbiota and host physiology, varies between individuals. Factors predicting the response to RS are not yet established and would be useful for developing precision nutrition approaches that maximize the benefits of dietary fiber intake. We sought to identify predictors of gut microbiota response to RS supplementation. We enrolled 76 healthy adults into a 7-week crossover study with 59 individuals completing the study. Participants consumed RS type 2 (RS2), RS type 4 (RS4), and digestible starch, for 10 d each with 5-d washout periods in between. We collected fecal and saliva samples and food records during each treatment period. We performed 16S rRNA gene sequencing and measured fecal short-chain fatty acids (SCFAs), salivary amylase (AMY1) gene copy number, and salivary amylase activity (SAA). Dietary fiber intake was predictive of the relative abundance of several amplicon sequence variants (ASVs) at the end of both RS treatments. AMY1-related metrics were not predictive of response to RS. SAA was only predictive of the relative abundance of one ASV after digestible starch supplementation. Interestingly, SCFA concentrations increased the most during digestible starch supplementation. Treatment order (the order of consumption of RS2 and RS4), alpha diversity, and a subset of ASVs were predictive of SCFA changes after RS supplementation. Based on our findings, dietary fiber intake and gut microbiome composition would be informative if assessed prior to recommending RS supplementation because these data can be used to predict changes in specific ASVs and fecal SCFA concentrations. These findings lay a foundation to support the premise that using a precision nutrition approach to optimize the benefits of dietary fibers such as RS could be an effective strategy to compensate for the low consumption of dietary fiber nationwide.

Effectiveness of Psychobiotic Bifidobacterium breve BB05 in Managing Psychosomatic Diarrhea in College Students by Regulating Gut Microbiota: A Randomized, Double-Blind, Placebo-Controlled Trial.

Diarrhea of college students (DCS) is a prevalent issue among college students, affecting their daily lives and academic performance. This study aims to explore the potential effect of Bifidobacterium breve BB05 supplements on the DCS. Initially, fifty healthy and fifty diarrheal students were recruited in the observational experiment and allocated into control and diarrhea groups, respectively. Subsequently, one hundred diarrheal students were newly recruited in the intervention experiment and randomly allocated into placebo and probiotic groups, both treated for 2 weeks. Questionnaires (BSS, HAMA-14, and HDRS-17) were performed to assess the students' diarrheal states and mental health at baseline and post-treatment. Fecal samples underwent 16S rRNA sequencing and Enzyme-Linked Immunosorbent Assay to evaluate gut microbiota and fecal metabolite alternations. Results indicated that B. breve BB05 supplementation significantly enriched (p < 0.05) the reduced gut microbial diversity caused by diarrhea. Diarrhea resulted in notable alterations in gut microbiota composition, as exhibited by elevated Collinsella and Streptococcus, alongside substantially decreased Bifidobacterium, Bacteroides, and Prevotella, while B. breve BB05 supplementation partially restored the compromised gut microbiota at both the phylum and genus levels, particularly by increasing Bifidobacterium and Roseburia (p < 0.05). Importantly, questionnaire results suggested that B. breve BB05 administration achieved superior efficacy in relieving diarrhea symptoms and the associated anxiety and depression in college students. An increased fecal concentration of 5-hydroxytryptamine (5-HT) was also observed in the probiotic group, while Acetylcholine (ACH), Epinephrine (EPI), and Noradrenaline/Norepinephrine (NANE) reduced, revealing the potential of B. breve BB05 in alleviating anxiety and depression via modulating the microbiota-gut-brain axis. Furthermore, correlation analysis suggested that the altered microbiota and fecal neurotransmitters were closely associated with the mental symptoms. These results endorse B. breve BB05 intervention as a promising and innovative approach to alleviate both diarrhea and mental health conditions among college students.

Improvement of insulin sensitivity by dietary fiber consumption during late pregnant sows is associated with gut microbiota regulation of tryptophan metabolism

BackgroundDietary fiber (DF) consumption was reported to improve insulin sensitivity, change the tryptophan metabolism, and alter the gut microbiota. Herein, this study aimed to investigate the effects of DF consumption on insulin sensitivity, tryptophan metabolism, and gut microbiota composition in sows during late pregnancy, and explore the relationship between tryptophan metabolites and insulin sensitivity regulated by DF supplementation.ResultsTwelve sows were randomly assigned to two dietary treatment groups (six/group): the low-fiber (LF) group, which was fed a basal diet, and the high-fiber (HF) group, which was fed the basal diet supplemented with 22.60 g/kg inulin and 181.60 g/kg cellulose. During late pregnancy, meal test, glucose tolerance test, and insulin challenge test were used to investigate the insulin sensitivity of sows, using the percutaneous brachiocephalic vein catheterization technique. High DF consumption resulted in improved insulin sensitivity, especially during the second and third trimesters, and promoted serotonin production from tryptophan. Additionally, plasma serotonin concentration was positively correlated with the insulin sensitivity index during late pregnancy. Moreover, DF consumption elevated fecal short-chain fatty acid (SCFA) concentrations, altered fecal microbial diversity, and increased the abundances of Rikenellaceae_RC9_gut_group, Alloprevotella, Parabacteroides, Roseburia, and Sphaerochaeta, which were positively correlated to plasma serotonin concentration.ConclusionsDF consumption improved insulin sensitivity during late pregnancy in sows, which improved microbial diversity in fecal samples and increased fecal SCFA concentrations, resulting in a positive correlation with plasma serotonin level.

Fecal microbiota and concentrations of long-chain fatty acids, sterols, and unconjugated bile acids in cats with chronic enteropathy.

Feline chronic enteropathies (FCE) are common causes of chronic gastrointestinal signs in cats and include different diseases such as food-responsive enteropathy (FRE), inflammatory bowel diseases (IBD), and low-grade intestinal T-cell lymphoma (LGITL). Although changes in intestinal microbiota and fecal metabolites have been reported in dogs and humans with chronic enteropathy, research in cats has been limited. Therefore, this study aimed to evaluate the fecal microbiota and lipid-related fecal metabolites in cats with FCE to a clinically healthy comparison group (CG). A total of 34 cats with FCE (13 FRE, 15 IBD, and 6 LGITL) and 27 cats in the CG were enrolled in this study. The fecal microbiota was evaluated by the qPCR-based feline Dysbiosis Index (DI). The feline DI in cats with CE (median: 1.3, range: -2.4 to 3.8) was significantly higher (p < 0.0001) compared to CG (median: - 2.3, Range: -4.3 to 2.3), with no difference found among the FCE subgroups. The fecal abundances of Faecalibacterium (p < 0.0001), Bacteroides (p < 0.0001), Fusobacterium (p = 0.0398), Bifidobacterium (p = 0.0004), and total bacteria (p = 0.0337) significantly decreased in cats with FCE. Twenty-seven targeted metabolites were measured by gas chromatography-mass spectrometry, including long-chain fatty acids (LCFAs), sterols, and bile acids (BAs). Fecal concentrations of 5 of 12 LCFAs were significantly increased in cats with FCE compared to CG. Fecal concentrations of zoosterol (p = 0.0109), such as cholesterol (p < 0.001) were also significantly increased in cats with FCE, but those of phytosterols were significantly decreased in this group. No differences in fecal BAs were found between the groups. Although no differences were found between the four groups, the fecal metabolomic pattern of cats with FRE was more similar to that of the CG than to those with IBD or LGITL. This could be explained by the mild changes associated with FRE compared to IBD and LGITL. The study showed changes in intestinal microbiota and alteration of fecal metabolites in FCE cats compared to the CG. Changes in fecal lipids metabolites suggest a dysmetabolism of lipids, including LCFAs, sterols, and unconjugated BAs in cats with CE.

Gas Concentration Measuring-System (CH4, NH3, CO2) Upon Cow Feces in an Encased-Space Based on Arduino Uno

The goal of this exploration is to fabricate an estimating instrument for perceiving Methane, Smelling salts, and Carbon Dioxide gas concentrations in cow feces within a confined space. The feasibility of gas concentration detection devices using MQ-2 sensors, MQ-4 sensors, and Arduino Uno-based MQ-135 sensors will also be tested. This research relates to physics, particularly instrument physics. The research will employ hardware design, software design, and testing methodologies. The gas used for testing was produced from 500 grams of cow feces through three treatments: no treatment, addition of 50 grams of activated charcoal, and addition of 50 milliliters of EM4. The tool validation test was conducted by three experts, and the typical worth acquired was 95.8%, classified as entirely achievable. The experiment yielded the highest concentrations of CH4, NH3, and CO2 gases at 11:30 AM (plus EM4), 03:00 AM (plus EM4), and 24:00 AM (without treatment), respectively, with readings of 9.49 ppm, 26.89 ppm, and 4.57 ppm.

Seasonal variation in heavy metal intake and excretion by dairy cattle in an Indian megacity

Milk consumption plays a pivotal role in human nutrition, especially for children, due to its high protein, calcium, and vitamin contents that aid cognitive development. Nonetheless, potential hazards from heavy metal presence in milk, due to environmental exposure and intake through feed, have gained global attention. Given paucity of data we investigated the seasonal variation in the quantitative intake of heavy metals (cadmium: Cd, chromium: Cr, lead: Pb) by dairy cows in the South Indian megacity of Bengaluru, and the resulting heavy metal concentrations in milk and feces. The research involved 39 dairy farms across urban and peri‑urban areas, where 281 feed, 329 milk, and 183 feces samples were collected along with management data during monsoon (July 2020 - August 2020), winter (November 2020 – February 2021) and summer (March 2022 – June 2022) seasons. During the summer season, Cd concentration in lake fodder averaged 1.6 mg/kg DM, which was higher than the 0.6 mg/kg DM during winter and 0.9 mg/kg DM during the monsoon season. The higher concentration resulted in an increased daily Cd intake of 13.7 mg/cow/day. Similarly, Cr and Pb intake were also highest in summer (Cr: 46.3 mg/cow/day, Pb: 11.7 mg/cow/day), whereby for both elements the concentrations were higher in non-lake feed than in lake fodder. With the exception of a few milk samples, Cr and Pb concentrations were below threshold levels and did not compromise milk safety, and Cd levels never raised concerns. Nevertheless, elevated Cr and Pb concentrations (Cr: 9.8–16.9 mg/kg DM, Pb: 4.1–10.6 mg/kg DM) were determined in feces across seasons, potentially endangering the environment and reintroducing these elements into the food chain through manure application on agricultural land. Rather than uniformly discouraging the use of lake fodder in Bengaluru, authorities on the one hand should caution fodder usage in pollution-prone areas, and on the other hand take measures to reduce contamination levels at those sites. Furthermore, it appears necessary to implement more stringent control measures for other types of feedstuffs. Raising farmers' awareness of the problem of heavy metals in the food chain could promote their compliance with regulations without the need for complete feed bans, which are difficult to enforce in a highly contested urban environment.

Salivary calprotectin and neutrophils in inflammatory bowel disease in relation to oral diseases

AbstractObjectiveCalprotectin is elevated in saliva from inflammatory bowel disease (IBD) patients, but it is also affected by oral disease. We assessed the salivary concentration of calprotectin in IBD patients, in relation to intestinal and oral diseases. Furthermore, we investigated the phenotype of salivary neutrophils from IBD patients, and their ability to secrete calprotectin.Materials and MethodsThirty IBD patients and 26 controls were orally examined and sampled for stimulated saliva. Twenty‐five IBD patients provided fresh fecal samples. Calprotectin concentrations in saliva and feces were determined by an enzyme‐linked immunosorbent assay. Expression of CD11b, CD15, and CD16 on oral neutrophils was assessed by flow cytometry. Secretion of calprotectin was evaluated in cultured oral neutrophils.ResultsCalprotectin was significantly elevated in saliva of IBD patients compared to controls, particularly in Crohn's disease, irrespective of caries or periodontitis. Salivary calprotectin did not correlate to fecal calprotectin. CD11b expression was significantly reduced in salivary neutrophils from IBD patients. Salivary neutrophils from IBD patients tended to secrete more calprotectin than controls.ConclusionsSalivary calprotectin is elevated in IBD regardless of oral diseases. Furthermore, salivary neutrophils secrete calprotectin, and display lower CD11b expression in IBD.

Dry matter concentration, particle size distribution and sand presence in faeces from horses with and without colic

A study comprising 74 colic and 74 control horses admitted to an animal hospital was performed. Faecal samples were collected and analysed for dry matter concentration, particle size distribution using wet-sieving, and sand presence through a sand sedimentation test. Data on horse breed, age, gender and basic feeding variables was collected and analysed using χ2-tests. Faecal dry matter concentration, particle size distribution and sand score was compared between colic and non-colic horses, and between horses with different colic types, using one-way ANOVA. Results showed that colic and non-colic horse groups were similar in breed, age, gender and basic feeding variables. Faecal dry matter concentration, particle size distribution and sand score were similar among colic and non-colic horses. Horses diagnosed with “unknown colic cause” had higher proportion of particles >0.5 <1.0 mm size compared to horses with colic due to impactions in caecum or colon, torsion or gas accumulation (P<0.05), but this difference was very small and most likely not of biological importance. Faecal dry matter concentration and sand score were similar among horses with different types of colic. Increased knowledge of the composition of particles of different size in equine faeces may enhance our understanding of digesta passage rate in colic and non-colic horses, which is needed to develop preventative measures of certain types of colic.

Colonoscopy findings after increasing two-stool faecal immunochemical test (FIT) cut-off: Cross-sectional analysis of the SCREESCO randomized trial.

We determined the impact of an increased two-stool faecal immunochemical test (FIT) cut-off on colonoscopy positivity and relative sensitivity and specificity in the randomized controlled screening trial screening of Swedish colons conducted in Sweden. We performed a cross-sectional analysis of participants in the FIT arm that performed FIT between March 2014 and 2020 within the study registered with ClinicalTrials.gov, NCT02078804, who had a faecal haemoglobin concentration of at least 10µg/g in at least one of two stool samples and who underwent a colonoscopy (n=3841). For each increase in cut-off, we computed the positive predictive value (PPV), numbers needed to scope (NNS), sensitivity and specificity for finding colorectal cancer (CRC) and advanced neoplasia (AN; advanced adenoma or CRC) relative to cut-off 10µg/g. The PPV for AN increased from 23.0% (95% confidence intervals [CI]: 22.3%-23.6%) at cut-off 10µg/g to 28.8% (95% CI: 27.8%-29.7%) and 33.1% (95% CI: 31.9%-34.4%) at cut-offs 20 and 40µg/g, respectively, whereas the NNS to find a CRC correspondingly decreased from 41 to 27 and 19. The PPV for AN was higher in men than women at each cut-off, for example 31.5% (95% CI: 30.1%-32.8%) in men and 25.6% (95% CI: 24.3%-27.0%) in women at 20µg/g. The relative sensitivity and relative specificity were similar in men and women at each cut-off. A low cut-off of around 20-40µg/g allows detection and removal of many AN compared to 10µg/g while reducing the number of colonoscopies in both men and women.

Changes of faecal bacterial communities and microbial fibrolytic activity in horses aged from 6 to 30 years old.

Horse owners and veterinarians report that from the age of 15, their horses can lose body condition and be more susceptible to diseases. Large intestinal microbiome changes may be involved. Indeed, microbiota is crucial for maintaining the condition and health of herbivores by converting fibres into nutrients. This study aimed to compare the faecal microbiome in horses aged from 6 to 30 years old (yo), living in the same environment and consuming the same diet, in order to assess whether the parameters changed linearly with age and whether there was a pivotal age category. Fifty horses were selected from the same environment and distributed across four age categories: 6-10 (n = 12), 11-15 (n = 11), 16-20 (n = 13), and 21-30 (n = 14) yo. All horses had no digestive problems, had teeth suitable for consuming their feed, and were up to date with their vaccination and deworming programmes. After three weeks of constant diet (ad libitum hay and 860 g of concentrate per day), one faecal sample per horse was collected on the same day. The bacterial communities' richness and intra-sample diversity were negatively correlated with age. There was a new distribution of non-beneficial and beneficial taxa, particularly in the 21-30 yo category. Although the faecal concentration of short-chain fatty acids remained stable, the acetate proportion was negatively correlated with age while it was the opposite for the proportions of butyrate, valerate, and iso-valerate. Additionally, the faecal pH was negatively correlated with age. Differences were more pronounced when comparing the 6-10 yo and 21-30 yo categories. The values of the parameters studied became more dispersed from the 16-20 yo category onwards, which appeared as a transitional moment, as it did not differ significantly from the younger and older categories for most of these parameters. Our data suggest that the microbiome changes with age. By highlighting the pivotal age of 16-20, this gives the opportunity to intervene before individuals reach extremes that could lead to pathological conditions.

Effects of dietary fiber and biotic supplementation on apparent total tract macronutrient digestibility and the fecal characteristics, metabolites, and microbiota of healthy adult dogs.

Dietary fibers and biotics have been shown to support gastrointestinal health in dogs, but are usually tested individually. There is value in testing fiber-biotic combinations that are commonly used commercially. Therefore, this study was conducted to determine the apparent total tract macronutrient digestibility (ATTD) of diets supplemented with fibers or biotics and to evaluate their effects on the fecal characteristics, metabolites, microbiota, and immunoglobulin A (IgA) concentrations of dogs. Twelve healthy adult female beagle dogs (age= 6.2 ± 1.6 yr; body weight = 9.5 ± 1.1kg) were used in a replicated 3 x 3 Latin square design to test three treatments: 1) control diet based on rice, chicken meal, tapioca starch, and cellulose + a placebo treat (CT); 2) diet based on rice, chicken meal, garbanzo beans, and cellulose + a placebo treat (GB); 3) diet based on rice, chicken meal, garbanzo beans, and a functional fiber/prebiotic blend + a probiotic-containing treat (GBPP). In each 28-day period, a 22-day diet adaptation was followed by a 5-day fecal collection phase. Fasted blood samples were collected on day 28. Data were analyzed using the Mixed Models procedure of SAS 9.4, with P<0.05 being significant and P<0.10 being trends. ATTD of dry matter, organic matter, and energy were lower (P<0.001) and DM fecal output was higher (P<0.01) in dogs fed GBPP than CT or GB, whereas ATTD of crude protein was higher (P<0.001) in dogs fed CT and GBPP than GB. ATTD of fat was higher (P<0.001) and wet fecal output was lower (P<0.01) in dogs fed CT than GB or GBPP. Fecal DM% was higher (P<0.001) in dogs fed CT than GBPP or GB, and higher in dogs fed GBPP than GB. Fecal short-chain fatty acid concentrations were higher (P<0.001) in dogs fed GB than CT or GBPP, and higher in dogs fed GB than GBPP. Fecal IgA concentrations were higher (P<0.01) in dogs fed GB than CT. Fecal microbiota populations were affected by diet, with alpha diversity being higher (P<0.01) in dogs fed GB than CT, and beta diversity shifting following dietary fiber and biotic supplementation. The relative abundance of 24 bacterial genera were altered in dogs fed GB or GBPP than CT. Serum triglyceride concentrations were lower in dogs fed GB than GBPP or CT. Our results demonstrate that legume-based dietary fibers, with or without prebiotics and probiotics, reduce ATTD, increase stool output, beneficially shift fecal metabolites and microbiota, and reduce blood lipids of adult dogs.

#2070 Associations of fecal and plasma levels of SCFAs with gut microbiota and clinical characteristics in non-dialysis renal anemia patients

Abstract Background and Aims Renal anemia is one of the most common complications of Chronic Kidney Disease (CKD). The gut-kidney axis hypothesis has led to numerous studies showing that patients with CKD have a distinct gut microbiota structure compared with controls and that changes in gut microbiota correlate with disease severity and progression. The short-chain fatty acids (SCFAs) are speculated to be pivotal in the gut-kidney crosstalk. However, the role of SCFAs in renal anemia has not been elucidated. This study aimed to explore and compare the fecal and plasma levels of SCFAs in non-dialysis renal anemia patients and healthy controls to reveal the potential interactions among SCFAs, gut microbiota, and clinical features of renal anemia, which may provide new light on further studies. Method A cohort of 30 non-dialysis renal anemia patients and 20 healthy controls were recruited from the First Affiliated Hospital of Zhengzhou University. Gut microbiota was analyzed using 16S rRNA gene amplification sequencing. Fecal and plasma concentrations of SCFAs were measured using GC-MS/MS platform. The clinical characteristics of patients with renal anemia and controls were evaluated. Results Renal anemia patients displayed altered microbiota composition compared to healthy subjects. The relative abundance of Enterobacterales, Enterobacteriaceae, Escherichia-Shigella, and Escherichia-coli were higher in patients with renal anemia, and the Lachnospiraceae family decreased in renal anemia patients. In contrast, the relative abundance of Lachnospirales, Lachnospiraceae, and Bacteroides vulgatus was higher in the control group. Patients with renal anemia had higher fecal and plasma concentrations of SCFAs compared to controls. The fecal and plasma concentrations of SCFAs were significantly different not only between the patients with renal anemia and controls but also in the different severity of renal anemia. Moreover, different types of SCFAs are intimately associated with clinical characteristics. The applications of medications may exert effects on the fecal and plasma SCFAs. A positive correlation was obtained between Lachnospirales and the plasma SCFAs. The levels of acetic acid and caproic acid in fecal and the levels of acetic acid, propionic acid, and butyric acid in plasma were all positively correlated with the abundance of Cyanobacteria. Conclusion The gut metabolites SCFAs are tightly linked to the alterations of gut microbiota and clinical characteristics of renal anemia. Further studies are warranted to elucidate the relationships more in-depth.

Meta-analysis of shotgun sequencing of gut microbiota in Parkinson’s disease

We aimed to identify gut microbial features in Parkinson’s disease (PD) across countries by meta-analyzing our fecal shotgun sequencing dataset of 94 PD patients and 73 controls in Japan with five previously reported datasets from USA, Germany, China1, China2, and Taiwan. GC-MS and LC-MS/MS assays were established to quantify fecal short-chain fatty acids (SCFAs) and fecal polyamines, respectively. α-Diversity was increased in PD across six datasets. Taxonomic analysis showed that species Akkermansia muciniphila was increased in PD, while species Roseburia intestinalis and Faecalibacterium prausnitzii were decreased in PD. Pathway analysis showed that genes in the biosyntheses of riboflavin and biotin were markedly decreased in PD after adjusting for confounding factors. Five out of six categories in carbohydrate-active enzymes (CAZymes) were decreased in PD. Metabolomic analysis of our fecal samples revealed that fecal SCFAs and polyamines were significantly decreased in PD. Genes in the riboflavin and biotin biosyntheses were positively correlated with the fecal concentrations of SCFAs and polyamines. Bacteria that accounted for the decreased riboflavin biosynthesis in Japan, the USA, and Germany were different from those in China1, China2, and Taiwan. Similarly, different bacteria accounted for decreased biotin biosynthesis in the two country groups. We postulate that decreased SCFAs and polyamines reduce the intestinal mucus layer, which subsequently facilitates the formation of abnormal α-synuclein fibrils in the intestinal neural plexus in PD, and also cause neuroinflammation in PD.

Effect of grinding or rolling fava beans on feed intake and milk production in Holstein cows

The objective of the present study was to evaluate the performance of primi- and multiparous dairy cows fed diets with ground or rolled fava beans (FB). A total of 96 Danish Holstein cows (48 primi- and 48 multiparous) were used in a randomized block design lasting 4 weeks. Within parity group, cows were blocked according to their milk yield in 6 blocks with 8 cows each and two cows from each block were distributed in pens where they were assigned randomly one of the two experimental diets. The diets were based on a total mix ration (TMR) composed of 52.6 % forage and 47.4 % concentrate (DM basis), differing only in the particle size of FB (geometric mean diameters of 1.02 and 3.52 mm for ground and rolled FB, respectively). Feed intake, milk production, and milk composition were determined during the last 8 days of the experimental period; none of these differed between treatments except for a higher (P = 0.01) milk N efficiency (% of N intake) and milk urea content with ground FB compared with rolled FB. Additionally, feces and ruminal fluid were collected from a group of 24 multiparous cows to determine fecal starch content and ruminal volatile fatty acids (VFAs). The fecal starch concentration was greater with rolled FB showing a reduced starch digestion, whereas ruminal VFA proportions generally did not differ between treatments. In conclusion, the lactation performance of dairy cows appeared not to be affected by grinding or rolling of FB with a 20 % FB inclusion in the DM diet, even though total tract starch digestion was reduced with greater FB particle size.