Search Results (1,943)

The mechanisms of nutritional niche differentiation among sympatric Schizothoracinae fishes play an important role in their adaptive evolution and should be considered in conservation strategies. To date, there have been no reports about the role of different feeding strategies in nutritional niche differentiation among five Schizothoracinae species (Ptychobarbus leptosomus, PL; Gymnodiptychus pachycheilus, GP; Schizothorax kozlovi, SK; Schizopygopsis malacanthus, SM; and S. wangchiachii, SW). This study explored the role of feeding strategy differences in nutritional niche differentiation among sympatric Schizothoracinae fishes. We analyzed feeding/digestive organ morphology, diet composition, intestinal digestive enzyme activity, and microbial diversity in five species from the middle Yalong River. The results revealed dietary divergence: PL consumed small fish, invertebrates, and algae; GP/SK fed on invertebrates and algae; and SM/SW primarily ate algae. Additionally, α-amylase activity was lower in PL/GP/SK than in SM/SW (p < 0.05), while lipase activity was lower in SM/SW than in PL/GP/SK (p < 0.05), and PL exhibited the highest trypsin activity (p < 0.05). The intestinal microbial composition/diversity also varied: the PL group differed significantly from the GP + SK and SM + SW groups (p < 0.05), with Cetobacterium being dominant in the PL group and Clostridium being dominant in the other groups; the α diversity was highest in the SM + SW group and lowest in the PL group. PICRUSt2 predictions revealed significant differences in nutrient metabolism pathways between the PL group and the other groups (p < 0.05). Overall, the morphological differences in feeding/digestive organs and recent food intake may drive the dietary divergence, inducing adaptive changes in digestive enzymes and microbial diversity and ultimately promoting nutritional niche differentiation among sympatric Schizothoracinae species. Full article

This study compared serum immunological parameters, cytokines, intestinal permeability, fecal microbiota, and short-chain fatty acids (SCFAs) between healthy and diarrheic suckling calves. Serum and facecal samples were analyzed using ELISA kits, 16S rDNA sequencing, and targeted metabolomics. Compared with healthy calves, the serum levels of aspartate aminotransferase, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), endotoxin (ET), and diamine oxidase (DAO) were significantly higher (p < 0.05), whereas the serum levels of immunoglobulin A (IgA), immunoglobulin G (IgG), and interleukin-10 (IL-10) were significantly lower in diarrheic calves (p < 0.05). The contents of propionic acid, butyric acid, and valeric acid significantly decreased in the fecal of diarrheic calves (p < 0.05). Moreover, the Chao1 and observed_features index of fecal microbiota significantly decreased in diarrheic calves (p < 0.05). The relative abundance of Escherichia-Shigella, Clostridium_sensu_stricto_1, and Streptococcus was significantly higher (p < 0.05), whereas Phascolarctobacterium, Ruminococcus torques group, and Faecalibacterium were significantly lower in diarrheic calves (p < 0.05). Escherichia-Shigella abundance was positively correlated with ET, DAO, IL-1β, and TNF-α levels (p < 0.05). Faecalibacterium abundance was significantly positively correlated with IgG, IgA, IL-10, and butyric acid but negatively correlated with ET and DAO levels (p < 0.05). In summary, diarrheic suckling calves exhibited reduced immune function, inflammatory response, and increased intestinal permeability. The relative abundance of fecal microbiota of Escherichia-Shigella and Clostridium_sensu_stricto_1 increased, while propionic acid, butyric acid, and valeric acid concentration were decreased in calves with diarrhea. This underscores the critical interplay between microbiota balance and gut health in diarrhea. Full article

The increasing prevalence of antimicrobial resistance in livestock pathogens necessitates the development of effective alternatives to conventional antibiotics. This review aims to assess the potential of antimicrobial peptides (AMPs) as alternatives to traditional antibiotics in farm animal production systems, examining their mechanisms of action, efficacy, and applications. A thorough examination of recent literature was conducted to evaluate the properties, classification, and mechanisms of action of AMPs, their natural occurrence, and their applications in poultry, swine, and ruminant production. The review also compared AMPs with conventional antibiotics, antifungals, and antiparasitic drugs. Specific AMPs have shown effectiveness against livestock pathogens, including Escherichia coli, Salmonella, and Clostridium perfringens, along with drug-resistant fungi. One of the primary benefits of AMPs is their strong antimicrobial activity against a wide range of pathogens relevant to farm animal health. Innovative delivery systems, such as self-assembly techniques and nanoparticle encapsulation, can tackle the stability and bioavailability issues associated with AMP administration in farm settings. AMPs represent promising alternatives to conventional antimicrobials in livestock production, offering significant benefits, including a reduced risk of resistance development, immunomodulatory effects, and broad-spectrum activity. However, addressing disadvantages related to production costs, stability, and delivery systems is crucial for their successful commercial application. Integrating AMPs into sustainable farming, after overcoming their shortcomings, could significantly contribute to global efforts to combat antimicrobial resistance. Full article

Low-fishmeal feed is increasingly being adopted across the global aquaculture industry. This study evaluated dietary Clostridium butyricum and alanyl-glutamine (Ala-Gln) supplementation in juvenile triploid rainbow trout (Oncorhynchus mykiss) with a low-fishmeal diet. Four diets were tested: basal diet (SBM, 15% fishmeal and 21.6% soybean meal), SBM + 0.5% C. butyricum (CB), SBM + 1.0% Ala-Gln, and SBM + 0.5% C. butyricum + 1.0% Ala-Gln (CB-AG). Fish were fed in 500 L tanks in recirculating aquaculture systems for 8 weeks (62.52 ± 0.47 g). Each group comprised three tanks, with each tank housing 30 fish. Then 10 fish per tank were challenged with Aeromonas salmonicida. CB-AG showed significantly higher weight gain and specific growth rates than the SBM group (p < 0.05). Mortality was significantly lower in CB-AG and AG than in SBM after A. salmonicida challenge. Histomorphology revealed significant differences (p < 0.05) between CB-AG and SBM in muscularis thickness, villus width, and height. SBM sections showed inflammatory infiltration and border damage were attenuated in supplemented groups. Serum malondialdehyde (MDA) and dioxygenase (DAO) were significantly lower in CB-AG than SBM (p < 0.05), while serum and hepatic lysozyme (LZM) and hepatic superoxide dismutase (SOD) were higher. Digestive enzymes indicated significantly higher trypsin and lipase activities in CB-AG (p < 0.05). CB-AG upregulated intestinal tight junction proteins and PepT1 and downregulated pro-inflammatory mediators. Combined 0.5% C. butyricum and 1.0% Ala-Gln inclusion effectively preserved growth performance, antioxidant capacity, gut microbiome homeostasis, and intestinal health in rainbow trout on low-fishmeal diets. Full article

Clostridium perfringens is responsible for various diseases. Foodborne outbreaks (FBOs) result from the in situ production of C. perfringens enterotoxin (CPE) by type F strains during sporulation. The cpe gene can be plasmidic (p-cpe) or chromosomal (c-cpe). Strains (c-cpe) exhibit greater heat resistance and are frequently associated with FBO. Strains cpe-negative are considered heat-sensitive. This study investigates the sporulation abilities and heat resistance of eight C. perfringens strains isolated from French foodborne outbreaks. Whole-genome sequencing classified the strains into two clades: the “chromosomal cpe clade,”, mainly composed of cpe-positive strains with c-cpe and some cpe-negative strains, and the “plasmidic cpe clade,”, primarily containing cpe-negative strains and a few with plasmid-borne cpe. Sporulation assays and thermal inactivation kinetics were performed on FBO strains to evaluate the influence of genetic variability on sporulation abilities and heat resistance. Experimental analyses revealed that strains within the “chromosomal cpe clade” exhibited the highest sporulation abilities, regardless of cpe presence, while those in the “plasmidic cpe clade” had low sporulation ability. Moreover, heat-resistant spores were produced exclusively by strains of the “chromosomal cpe clade,” with c-cpe strains exhibiting the highest heat resistance (δ_{95 °C} ≈ 49 min), followed by cpe-negative strains (δ_{95 °C} ≈ 9.5 min). p-cpe strains exhibited a heat-sensitive phenotype, with δ_{85 °C} values of 12 min. A key finding of this study is the identification of a group with intermediate heat resistance, distinct from the highly heat-resistant (c-cpe) and heat-sensitive (p-cpe) strains. This intermediate heat-resistance phenotype, observed in cpe-negative strains within the “chromosomal cpe clade,” offers a new perspective on C. perfringens stress adaptation, suggesting their potential for persistence in food. Their heat resistance, along with the potential for cpe gene transfer, could make these strains a relevant hazard for cooked, cooled, and re-heated meat products. Full article

Background/Objectives: Calves have immature immune systems, hence immunization with vaccines is essential to protect them from infectious diseases. However, immune responses to vaccines vary widely among individuals. Therefore, strategies for enhancing vaccine efficacy are needed, particularly those targeting low responders to vaccines. Probiotics have attracted attention because of their beneficial immunomodulatory effects on the host. Although probiotics may improve calf immunity, their potential to enhance immune responses to vaccines in calves remains unclear. Thus, we investigated whether immune responses to vaccines, especially T-cell responses, are enhanced when calves receive a combination of probiotic supplementation and vaccination. Methods: Calves were divided into three feeding groups, as follows: negative control feed, live bacteria-mixed feed (Zeosapo KB), and Clostridium butyricum-only feed (CB). After weaning, all calves received two doses of a live attenuated hexavalent viral vaccine. T-cell responses to a vaccine antigen were evaluated by measuring the expression levels of lymphocyte activation markers CD25 and CD69, as well as Th1 cytokine production, in peripheral blood mononuclear cell culture assays. Results: CD25 expression significantly increased in CD4⁺ T cells four weeks after the booster vaccination in the Zeosapo KB- and CB-fed groups. In addition, the CD25⁺CD69⁺ cell ratio in CD4⁺ T cells was increased in these groups. The production of Th1 cytokines in the culture supernatant was also increased in the CB-fed group. Conclusions: This clinical study demonstrates that probiotics activate CD4⁺ T cells and enhance Th1 cytokine responses in vaccinated calves. Full article

Xylooligosaccharides (XOS) are functional oligosaccharides with recognized prebiotic properties and growing industrial relevance, typically obtained through enzymatic depolymerization of xylan-rich lignocellulosic substrates. In this study, a recombinant endo-β-1,4-xylanase (XynA) from Clostridium acetobutylicum was employed for XOS production. The xynA gene was cloned into the expression vector pET-21a(+) and heterologously expressed in Escherichia coli BL21(DE3) under induction with isopropyl β-D-1-thiogalactopyranoside (IPTG). The recombinant protein, with an estimated molecular mass of 37.5 kDa, was verified by SDS-PAGE and Western blot analysis. Functional characterization via thin-layer chromatography revealed that XynA efficiently hydrolyzed beechwood xylan and rye arabinoxylan, predominantly yielding xylobiose. Additionally, the enzyme catalyzed the conversion of xylotriose into xylobiose and trace amounts of xylose. Notably, XynA demonstrated hydrolytic activity against autohydrolysed and alkali-pretreated coconut husk biomass, facilitating the release of XOS. These results underscore the potential of C. acetobutylicum XynA as a biocatalyst for the valorization of lignocellulosic residues into high-value oligosaccharides. Full article

Serotonin, a tryptophan metabolite, exerts a significant influence on both brain and gut functionality. While previous research has elucidated the intricate dynamics of the gut–brain axis, the interplay between serotonin pathway metabolites and gut microbiota in individuals undergoing hemodialysis remains largely unexplored. Therefore, this study aimed to investigate gut microbiota composition corresponding to serotonin pathway metabolite levels among patients with hemodialysis. A total of 85 patients undergoing hemodialysis were selected. Their gut microbiota was analyzed using shotgun metagenomic sequencing profiling. The serotonin pathway metabolites, including 5-hydroxytryptophan (5-HTP), serotonin, 5-methoxytryptophan (5-MTP), 5-methoxytryptamine, melatonin, and 6-hydroxymelatonin, were analyzed with the liquid chromatograph–tandem mass spectrometer. The robust linear discriminant analysis Effect Size (LEfSe) was employed to reveal the gut microbiota signature according to levels of serotonin pathway metabolites. A significant β-diversity difference in 5-Methoxytryptamine (p = 0.037) was found, while no variance in α-diversity was detected. Using LefSe analysis, we identified an enriched Tannerellaceae family in the high-hydroxytryptophan (5-HTP) group, the Odoribacteraceae family in the high-serotonin group, the Eubacteriales order in the high-5-methoxytryptophan (5-MTP) group, the Prevotella copri species in the high-5-Methoxytryptamine group, and the Clostridium genus in the high-melatonin group. In contrast, an enriched Clostridiaceae family in the low-5-HTP group, the Clostridiaceae family in the low-serotonin group, and the Bacteroides ovatus species in the low-5-MTP group were found. Distinct gut microbiota signatures linked to serotonin pathway metabolites were identified in patients undergoing hemodialysis. These findings provide insights for future gut–brain axis research and may guide methods to modulate gut microbiota to influence serotonin metabolites. Full article

The actual role of certain viruses, such as coronavirus (RbCoV) and parvovirus (LBoV), in the digestive diseases of rabbitries remains poorly understood. For this reason, we conducted three different studies. In the detection frequency study, carried out using samples from both sick and healthy animals from farms with recurrent enteric problems, the presence and Cq values obtained by qPCR for these two viruses supported their implication in digestive disorders. In the lesional study, performed on samples from farms experiencing enteric disease outbreaks, the presence of lesions characteristic of both viruses was confirmed, along with other viral, bacterial, and parasitic agents that may have exacerbated the condition. Finally, in the epidemiological study, using samples from rabbits of different ages from farms with enteric problems, a higher prevalence of these viruses was observed during the growing phase, with a significant association with other bacterial agents such as Escherichia coli and Clostridium spiroforme. Overall, these results highlight the importance of both viruses in the aetiology of enteric disease and support their inclusion in the diagnostic enteric profile for rabbits. Full article

The intestinal microbiota plays a crucial role in maintaining epithelial barrier integrity, while its impairment and the resulting inflammation contribute to numerous human pathologies. To preserve intestinal homeostasis, various probiotics are being developed; however, their selection and validation require accessible yet physiologically relevant models. We recently established a high-throughput Gut-on-Chip model comprising human epithelial (Caco-2) cells and peripheral blood mononuclear cells (PBMCs), demonstrating epithelial barrier disruption and pro-inflammatory cytokine secretion upon inflammation induction. The present study aimed to evaluate the feasibility of co-culturing anaerobic members of the human intestinal microbiota within this model and to assess their effects on inflammation-induced epithelial damage. We successfully co-cultured five intestinal anaerobic bacterial species in direct contact with the epithelial monolayer for two days. As proof of concept, we demonstrate that live Bacteroides thetaiotaomicron and its supernatant preserve epithelial barrier integrity and attenuate CCL2 secretion by Caco-2 cells. In contrast, Clostridium scindens did not prevent epithelial damage but suppressed CCL20 secretion, revealing a promising target for future studies. By recapitulating some of the key aspects of intestinal inflammation, we suggest that the current Gut-on-Chip model has potential as an easy-to-use platform for screening next-generation probiotics and live biotherapeutics with homeostatic and immunomodulatory properties. Full article

Metastatic breast carcinoma (BC) cells are prone to spreading in the bone microenvironment, leading to a vicious cycle between local osteoclast-mediated osteolysis and tumor progression. Therefore, the targeted pharmacological down-modulation of BC cell proliferation as well as osteoclast differentiation and hyperactivity might represent a promising treatment option. We developed a multifunctional peptide nanocarrier combining bioactive EPI-X4 peptides and the Rho-inhibiting C3bot enzyme from Clostridium botulinum. C3bot is preferentially internalized into the cytosol of monocytic cells, including osteoclasts, where it inhibits Rho-mediated signal transduction. However, Rho-mediated cellular processes like migration and cell division can also be inhibited in non-monocytic cells if C3bot is delivered into their cytosol by a nanocarrier. To accomplish this, we designed a supramolecular transporter where one molecule of biotinylated C3bot and three biotinylated entities of the human EPI-X4 peptide-derived CXCR4 antagonist JM173 are assembled on avidin as a central platform. This modular transport system (JM173)₃-Avi-C3 down-modulated osteoclast formation and hyperactivity and delivered the therapeutic cargo C3bot successfully into the cytosol of breast cancer cells, where it inhibited Rho. Full article

The expanding use of rare earth elements (REEs) in high-tech industrials has increased their environmental release, raising concerns about their ecological risks. This study employed the Diffusive Gradients in Thin Films (DGT) technique to assess REE bioavailability, spatial distribution, and ecological risks of REEs in sediments of the Yitong River, a historically polluted urban river in Changchun, China. Sediment characteristics (organic matter, pH, salinity), nutrient dynamics (N, P), and metal concentrations (Fe, Mn, As, etc.) were analyzed alongside REEs to evaluate their interactions and environmental drivers. Results revealed that REE concentrations (0.453–1.687 μg L⁻¹) were dominated by light REEs (50.1%), with levels an order of magnitude lower than heavily industrialized regions. Ecological risk quotients (RQ) for individual REEs were below thresholds (RQ < 1), indicating negligible immediate risks, though spatial trends suggested urban runoff influences. Probabilistic risk assessment integrating DGT data and species sensitivity distributions (SSD) estimated a low combined toxic probability (2.26%) for REEs and nutrients. Microbial community analysis revealed correlations between specific bacterial (e.g., Clostridium, Dechloromonas) and fungal genera (e.g., Pseudeurotium) with metals and REEs, highlighting microbial sensitivity to pollutant shifts. This study provides a multidimensional framework linking REE bioavailability, sediment geochemistry, and microbial ecology, offering insights for managing REE contamination in urban riverine systems. Full article

Dietary fiber has proven beneficial for improving gastrointestinal function, its role in the small intestine has received comparatively less attention. In this study, ten Erhualian pigs (40 ± 0.86 kg) were randomly assigned to two groups: a basal diet and a 7% wheat bran-supplemented diet, respectively. Using 16S rDNA sequencing and LC-MS-based untargeted metabolomics, we observed significant shifts in small intestinal microbiota and metabolome. Five genera (Terrisporobacter, Howardella, Romboutsia, Cellulosilyticum, and Intestinibacter) showed a significant increase in abundance in pigs fed the high-fiber diet. In addition, 155 differential metabolites were identified between the two groups. Functional enrichment analysis revealed that these metabolites were particularly enriched in pathways of carbohydrate utilization and tryptophan catabolism. Correlation analysis revealed significant associations between specific microbial genera and bile acids including lithocholic acid and 23-Norcholic acid. These findings indicate that a high-fiber diet may promote tryptophan metabolism by genera such as Clostridium_sensu_stricto_1, Terrisporobacter, and Romboutsia, facilitating intestinal function and health. Overall, our findings provide new insights into the effects of dietary fiber on the microbial community and metabolome in the small intestine, and highlight the potential of certain bacterial genera as beneficial microbiota for promoting small intestinal health. Full article

This study aimed to investigate the effects of dietary supplementation with TBZC on the growth performance, diarrhea incidence, antioxidant ability, immune function, and intestinal health of weaned piglets. A total of 120 weaned piglets were randomly allocated to one of three dietary treatments with six replicate pens and eight piglets per pen: CON—a basal diet; ZnO—a basal diet with 1500 mg Zn/kg from ZnO; and TBZC—a basal diet with 680 mg Zn/kg from TBZC. Following a 42-day period of consuming the zinc-enriched diet, the piglets were switched to a basal diet for the remaining 28 days of the trial. The dietary TBZC increased the average daily feed intake of weaned piglets (ADFI) from days 1 to 14 and the average daily growth (ADG) from days 43 to 70 compared with the ZnO group (p < 0.05). The supplementation with TBZC decreased the acid-binding capacity compared with the ZnO group (p < 0.05). Moreover, dietary TBZC decreased the MDA concentration and increased the GSH-Px concentration on day 14 and increased the SOD activity on day 28 and the GSH-Px concentration on day 70 compared with the ZnO group (p < 0.05). Compared with the ZnO group, the dietary TBAC supplementation increased (p < 0.05) the relative abundance of cecal Lactobacillus spp. and Blautia spp., while decreasing Blautia spp. in the colonic contents; increased (p < 0.05) the relative abundance of Prevotella spp. and Clostridium_sensu_stricto_1; and reduced (p < 0.05) Streptococcus spp. Therefore, replacing 1500 mg/kg of ZnO with 680 mg/kg of TBZC improves growth performance and antioxidant capacity and regulates gut microbes in weaned piglets. Full article

This study explored the potential therapeutic effect and possible mechanism of Atractylodes macrocephala Koidz. Polysaccharide (AP) on pirarubicin chemotherapy-induced depression (CID) in breast cancer mice. This study utilized a variety of techniques to explore the potential of AP in mitigating behavioral abnormalities and elucidate the role of gut microbiota regulation in its therapeutic effects on chemotherapy in breast cancer mice. These included a chemotherapy mouse model, behavioral assessments, histological analysis using hematoxylin and eosin staining, ultrastructural examination, enzyme-linked immunosorbent assays, 16S rDNA sequencing, metabolomic profiling, Western blot analysis, and a pseudo-germ-free animal model. Oral administration of AP significantly improved depression-like behaviors in breast cancer chemotherapy mice while also reducing neuronal damage and inflammation in the hippocampus. AP prevented ferroptosis of intestinal tissues caused by chemotherapy and had a repairing effect on the intestinal barrier damage of chemotherapy-induced mice. Additionally, AP enhanced gut microbiota composition and altered intestinal metabolites in chemotherapy-treated mice. It notably decreased the abundance of certain microbes, such as Bacteroidaceae, Lachnospiraceae, Oscillospiraceae, and Clostridium, while significantly increasing the abundance of Alistipes. Moreover, AP efficiently modulated intestinal metabolites, including glycocholic acid, L-Phenylalanine, and palmitoylcarnitine. More importantly, depletion of gut microbiota through antibiotics diminished the effectiveness of AP. Our results suggest that AP alleviates depression-like behaviors in chemotherapy-treated mice by regulating the gut microbiota and microbial metabolism, as well as suppressing ferroptosis in intestinal tissues. Full article