Sodium butyrate ameliorates thiram-induced tibial dyschondroplasia and gut microbial dysbiosis in broiler chickens.

Thiram is a dithiocarbamate pesticide widely used in agriculture as a fungicide for storing grains to prevent fungal diseases. However, its residues have threatened the safety of human beings and the stability of the ecosystem by causing different disease conditions, e.g., tibial dyschondroplasia (TD), which results in a substantial economic loss for the poultry industry. So, the research on TD has a great concern for the industry and the overall GDP of a country. In current study, we investigated whether different concentrations (300, 500, and 700 mg/kg) of sodium butyrate alleviated TD induced under acute thiram exposure by regulating osteogenic gene expression, promoting chondrocyte differentiation, and altering the gut microbial community. According to the findings, sodium butyrate restored clinical symptoms in broilers, improved growth performance, bone density, angiogenesis, and chondrocyte morphology and arrangement. It could activate the signal transduction of the Wnt/ß-catenin pathway, regulate the expression of GSK-3ß and ß-catenin, and further promote the production of osteogenic transcription factors Runx2 and OPN for restoration of lameness. In addition, the 16S rRNA sequencing revealed a significantly different community composition among the groups. The TD group increased the abundance of the harmful bacteria Proteobacteria, Subdoligranulum, and Erysipelatoclostridium. The sodium butyrate enriched many beneficial bacteria, such as Bacteroidetes, Verrucomicrobia, Faecalibacterium, Barnesiella, Rikenella, and Butyricicoccus, etc., especially at the concentration of 500 mg/kg. The mentioned concentration significantly limited the intestinal disorders under thiram exposure, and restored bone metabolism.

Cas9 regulated gene expression and pathogenicity in Riemerella anatipestifer.

Riemerellosis, a Riemerella anatipestifer infection, can cause meningitis, pericarditis, parahepatitis, and airsacculitis in ducks, leading to serious economic losses in the duck meat industry. However, the molecular mechanism of the pathogenesis and virulence factors of this infection are poorly understood. In the present study, we created a mutant strain RA-YMΔCas9 using trans-conjugation. Bacterial virulence tests indicated that the median lethal dose (LD50) of RA-YMΔCas9 was 5.01 × 107 CFU, significantly lower than that of the RA-YM strain, which was 1.58 × 105 CFU. The distribution and blood bacterial load from the infection groups showed no significant difference in the brain between the RA-YMΔCas9 mutant and the wild-type RA-YM strains, however, the number of mutant strains were significantly reduced in the liver, heart, and blood. Animal immunization experiments demonstrated that the intranasal administration of RA-YMΔCas9 in ducklings provided 80% protection after challenge with the wild-type strain, showing potential use as a live mucosal vaccine. RNAseq analysis indicated that Cas9 protein played a regulatory role in gene expression. This study is the first to report on the involvement of Cas9 in the regulation and pathogenesis of R. anatipestifer, and provides a theoretical basis for the development of relevant genetic engineering vaccines.

Deletion of the Riemerella anatipestifer type IX secretion system gene sprA results in differential expression of outer membrane proteins and virulence.

Riemerella anatipestifer (RA), the causative agent of infectious serositis that targets ducklings and other poultry, secretes protein via the type IX secretion system (T9SS). The proteins transported by T9SS are located on the bacterial cell surface or secreted into the extracellular milieu. In this study, a sprA deletion mutant was constructed encoding a core protein of T9SS to investigate its influence on outer membrane protein expression and its role in virulence. Compared with the wild-type RA-YM strain, the deletion mutant ΔsprA failed to digest gelatin, showed the same growth rate in the logarithmic phase and exhibited greater sensitivity to the bactericidal activity of duck sera, whereas the complemented strain restored these phenotypes. The outer membrane proteome of RA-YM and the ΔsprA mutant were analyzed by Tandem Mass Tags, which revealed 198 proteins with predicted localization to the cell envelope. Sixty-three of these proteins were differentially expressed in the outer membrane, with 43 up-regulated and 20 down-regulated. Among the twelve outer membrane proteins which were secreted by T9SS, four proteins were up-regulated and one protein was down-regulated. Animal experiments demonstrated that the median lethal dose of the mutant strain ΔsprA was about 500 times higher than that of the wild-type RA-YM strain, and bacterial loads in blood, brain, heart, liver and spleen of the ΔsprA-infected ducks were significantly reduced. Our results indicate that the SprA is a virulence-associated factor of RA, and its absence results in altered abundance of outer membrane proteins, and secretion disorders associated with some of the T9SS effector proteins.

Enterococcus faecium HDRsEf1 Protects the Intestinal Epithelium and Attenuates ETEC-Induced IL-8 Secretion in Enterocytes.

The probiotic Enterococcus faecium HDRsEf1 (Ef1) has been shown to have positive effects on piglet diarrhoea, but the mechanism has not yet been elucidated. In this study, using the IPEC-J2 cell line to mimic intestinal epithelial cells and enterotoxigenic Escherichia coli (ETEC) K88ac as a representative intestinal pathogen, the mechanism underlying Ef1 protection against an enteropathogen was investigated. The results demonstrated that Ef1 was effective in displacing K88ac from the IPEC-J2 cell layer. Moreover, Ef1 and its cell-free supernatant (S-Ef1) modulate IL-8 released by IPEC-J2 cells. Ef1 and its cell-free supernatant showed the potential to protect enterocytes from an acute inflammatory response. In addition, Ef1 and its cell-free supernatant increased the transepithelial electrical resistance (TEER) of the enterocyte monolayer, thus strengthening the intestinal barrier against ETEC. These results may contribute to the development of therapeutic interventions using Ef1 in intestinal disorders of piglets.

Pregnane X receptor is required for IFN-α-mediated CYP3A29 expression in pigs.

Pregnane X receptor (PXR) has been identified as a central mediator for coordinate responses to xenobiotic and drug metabolism, and is the major transcriptional regulator of cytochrome P-450 (CYP). Interferon (IFN)-α is known to induce antiviral mechanisms and exert immune regulatory capacity in various cell types. Here, we used primary porcine hepatocytes and a cultured hepatocyte cell line to identify the metabolic role of PXR in IFN-α-mediated CYP3A29 expression. We found that IFN-α could activate PXR in both time- and dose-dependent manners in pigs. Activation of PXR significantly increased CYP3A29 mRNA and protein expression. Meanwhile, the expression of CYP3A29 induced by IFN-α occurred after the increase of PXR expression in porcine hepatocytes. In addition, the IFN-α-induced CYP3A29 expression was blocked by PXR knockdown. The PXR-overexpressed cells (transfected with porcine PXR) increased CYP3A29 mRNA and protein expression. Furthermore, in animal experiments, we found that IFN-α increased both CYP3A29 mRNA and protein levels. Collectively, our results suggest that PXR plays an important role in IFN-α-mediated CYP3A29 expression in porcine hepatocytes.

Modulation of Gut Microbial Community and Metabolism by Bacillus licheniformis HD173 Promotes the Growth of Nursery Piglets Model.

Maintaining the balance and stability of the gut microbiota is crucial for the gut health and growth development of humans and animals. Bacillus licheniformis (B. licheniformis) has been reported to be beneficial to the gut health of humans and animals, whereas the probiotic effects of a new strain, B. licheniformis HD173, remain uncertain. In this study, nursery piglets were utilized as animal models to investigate the extensive impact of B. licheniformis HD173 on gut microbiota, metabolites, and host health. The major findings were that this probiotic enhanced the growth performance and improved the health status of the nursery piglets. Specifically, it reduced the level of pro-inflammatory cytokines IL-1ß and TNF-α in the serum while increasing the level of IL-10 and SOD. In the gut, B. licheniformis HD173 reduced the abundance of pathogenic bacteria such as Mycoplasma, Vibrio, and Vibrio metschnikovii, while it increased the abundance of butyrate-producing bacteria, including Oscillospira, Coprococcus, and Roseburia faecis, leading to an enhanced production of butyric acid. Furthermore, B. licheniformis HD173 effectively improved the gut metabolic status, enabling the gut microbiota to provide the host with stronger metabolic abilities for nutrients. In summary, these findings provide scientific evidence for the utilization of B. licheniformis HD173 in the development and production of probiotic products for maintaining gut health in humans and animals.

Regulation of the growth performance and the gastrointestinal microbiota community by the addition of defective pear fermentation to feed of small-tailed Han sheep.

This study investigated the effects of defective pear fermentation (DPF) diets on growth performance and gastrointestinal microbial communities in 60 healthy male small-tailed Han sheep, aged 90 days. The sheep were randomly divided into four groups, each consisting of three replicates with five sheep per replicate. Initially, all groups received a basal diet for seven days during the adaptation stage. Subsequently, for 60 days, group C (control) was fed a basal diet, group X received a basal diet with 2% DPF, group Y had a basal diet with 4% DPF, and group Z was fed a basal diet with 6% DPF. The results indicated that group Y experienced a significant increase in average daily gain (ADG) and average daily feed intake (ADFI). The addition of DPF significantly elevated the levels of GSH-Px and notably reduced MDA content compared to group C. Analysis of gastrointestinal microbiota showed that groups receiving DPF had increased relative abundances of Lachnospiraceae_NK3A20_group, norank_f p-2534-18B5_gut_group, Acetitomaculum, Actinobacteriota, Bacteroidota and Ruminococcus_gauvreauii_group, and decreased abundances of Proteobacteria, Prevotella, Staphylococcus, and Psychrobacter compared to group C. Group X exhibited the highest relative abundance of Olsenella, while group Y showed a significant increase in unclassified_f Lachnospiraceae compared to the other groups. Bacterial function prediction indicated that pathways related to energy metabolism were more prevalent in group X and Y. This study preliminarily confirms the feasibility of using DPF as feed additives, providing a foundation for further research and evaluation of DPF's application in animal production.

Effects of pomegranate (Punica granatum L.) peel on the growth performance and intestinal microbiota of broilers challenged with Escherichia coli.

The effects of pomegranate peel on the growth performance, intestinal morphology, and the cecal microbial community were investigated in broilers challenged with avian pathogenic Escherichia coli (APEC) O78. A total of 240 one-day-old chicks (120 males and 120 females) were randomly and evenly allotted into 4 treatment groups (each with 6 biological replicates each of 10 chicks), i.e., negative control (NC), positive control (PC), and 2 experimental groups treated with 0.2% fermented pomegranate peel (FP) and 0.2% unfermented pomegranate peel (UFP), respectively, with PC, FP, and UFP groups challenged with APEC O78 (5 × 108 CFU) on day 14. Results showed that the challenge of APEC O78 decreased the body weight (BW) and average daily gain (ADG) of broilers from 1 to 28 d (P < 0.01). These broilers exhibited more pathological conditions in the heart and liver and higher mortality rates in 28 d compared to the NC group. Diet supplemented with pomegranate peel (either fermented or unfermented) significantly increased BW, ADG, and the villus height/crypt depth ratio (VCR) of small intestine in 28 d compared to the NC group (P < 0.05). Results of the taxonomic structure of the gut microbiota showed that compared to the NC group, the APEC challenge significantly decreased the relative abundance of Bacteroidetes and increased the relative abundance of Firmicutes (P < 0.01). Compared to the PC group, the relative abundance of Ruminococcus_torques_group in FP group was increased, while the relative abundance of Alistipes was decreased. In summary, our study showed that the dietary supplementation of pomegranate peel could maintain the intestinal microbiota at a state favorable to the host, effectively reduce the abnormal changes in the taxonomic structure of the intestinal microbiota, and improve the growth performance in broilers treated with APEC.

Gene expression responses to Riemerella anatipestifer infection in the liver of ducks.

Riemerella anatipestifer is one of the most economically important pathogens of farm ducks worldwide. The molecular mechanisms that underlie its pathogenesis, particularly the host response to R. anatipestifer infection, are poorly understood. The differentially expressed gene profile of duck livers at 24 h following R. anatipestifer infection was therefore investigated using suppression subtractive hybridizaton analysis. A total of 45 differentially expressed genes were identified, which primarily included genes for proteins involved in acute-phase response, inflammatory response, immune response, wound healing and iron homeostasis. For the expression level of 20 genes from those 45 analysed by quantitative reverse transcriptase-polymerase chain reaction at 8, 24 and 48 h post infection, significant differences were observed among the three time points of measurements. The result from this study revealed a gene expression profile of duck liver during R. anatipestifer infection, and those genes with a role in the immune response and wound healing deserving further investigation to elucidate their respective roles during infection.

Outer membrane protein OMP76 of Riemerella anatipestifer contributes to complement evasion and virulence by binding to duck complement factor vitronectin.

Riemerella anatipestifer is an important bacterial pathogen in poultry. Pathogenic bacteria recruit host complement factors to resist the bactericidal effect of serum complement. Vitronectin (Vn) is a complementary regulatory protein that inhibits the formation of the membrane attack complex (MAC). Microbes use outer membrane proteins (OMPs) to hijack Vn for complement evasion. However, the mechanism by which R. anatipestifer achieves evasion is unclear. This study aimed to characterise OMPs of R. anatipestifer which interact with duck Vn (dVn) during complement evasion. Far-western assays and comparison of wild-type and mutant strains that were treated with dVn and duck serum demonstrated particularly strong binding of OMP76 to dVn. These data were confirmed with Escherichia coli strains expressing and not expressing OMP76. Combining tertiary structure analysis and homology modelling, truncated and knocked-out fragments of OMP76 showed that a cluster of critical amino acids in an extracellular loop of OMP76 mediate the interaction with dVn. Moreover, binding of dVn to R. anatipestifer inhibited MAC deposition on the bacterial surface thereby enhancing survival in duck serum. Virulence of the mutant strain ΔOMP76 was attenuated significantly relative to the wild-type strain. Furthermore, adhesion and invasion abilities of ΔOMP76 decreased, and histopathological changes showed that ΔOMP76 was less virulent in ducklings. Thus, OMP76 is a key virulence factor of R. anatipestifer. The identification of OMP76-mediated evasion of complement by recruitment of dVn contributes significantly to the understanding of the molecular mechanism by which R. anatipestifer escapes host innate immunity and provides a new target for the development of subunit vaccines.

Enterococcus faecium HDRsEf1 Promotes Systemic Th1 Responses and Enhances Resistance to SalmonellaTyphimurium Infection.

The gut microbiota is known to regulate the immune system and thereby influence susceptibility to infection. In this study, we observed that the administration of Enterococcus faecium HDRsEf1 (HDRsEf1) led to an improvement in the development of the immune system. This was evidenced by an increase in both the spleen index and the area of spleen white pulp. Specifically, the proportion of T helper (Th) 1 cells and the production of IFN-γ and IL-12 were significantly increased in the spleens of mice treated with HDRsEf1. In agreement with the in vivo results, we found that Th1-related cytokines, including IFN-γ and IL-12p70, were strongly induced in splenocytes treated with HDRsEf1. In addition, Th1 cell activation and high-level secretion of IL-12p70 were also confirmed by coculture of CD4+ T cells with bone marrow-derived dendritic cells treated with HDRsEf1. Moreover, the employment of HDRsEf1 was identified to augment resilience against systemic infection provoked by S. Typhimurium and stimulate the expression of the genes for TNFα and iNOS in the initial stage of infection, signifying that reinforced Th1 cells and IL-12 might activate macrophages for antibacterial safeguards. In summary, our study suggests that HDRsEf1 could act as an effective immunobiotic functional agent, promoting systemic Th1 immunological responses and priming defenses against infection.

Liver fat metabolism of broilers regulated by Bacillus amyloliquefaciens TL via stimulating IGF-1 secretion and regulating the IGF signaling pathway.

Bacillus amyloliquefaciens TL (B.A-TL) is well-known for its capability of promoting protein synthesis and lipid metabolism, in particular, the abdominal fat deposition in broilers. However, the underlying molecular mechanism remains unclear. In our study, the regulations of lipid metabolism of broilers by B.A-TL were explored both in vivo and in vitro. The metabolites of B.A-TL were used to simulate in vitro the effect of B.A-TL on liver metabolism based on the chicken hepatocellular carcinoma cell line (i.e., LMH cells). The effects of B.A-TL on lipid metabolism by regulating insulin/IGF signaling pathways were investigated by applying the signal pathway inhibitors in vitro. The results showed that the B.A-TL metabolites enhanced hepatic lipid synthesis and stimulated the secretion of IGF-1. The liver transcriptome analysis revealed the significantly upregulated expressions of four genes (SI, AMY2A, PCK1, and FASN) in the B.A-TL treatment group, mainly involved in carbohydrate digestion and absorption as well as biomacromolecule metabolism, with a particularly prominent effect on fatty acid synthase (FASN). Results of cellular assays showed that B.A-TL metabolites were involved in the insulin/IGF signaling pathway, regulating the expressions of lipid metabolism genes (e.g., FASN, ACCα, LPIN, and ACOX) and the FASN protein, ultimately regulating the lipid metabolism via the IGF/PI3K/FASN pathway in broilers.

A buffalo rumen-derived probiotic (SN-6) could effectively increase simmental growth performance by regulating fecal microbiota and metabolism.

Microorganisms play a key role in ruminal digestion, some of which can be used as probiotics to promote growth in ruminants. However, which potential bacteria are responsible for ruminant growth and how they potentiate the basic mechanism is unclear. In this study, three bacterial strains, Bacillus pumilus (SN-3), Bacillus paralicheniformis (SN-6), and Bacillus altitudinis (SN-20) with multiple digestive enzymes were isolated from the rumen of healthy buffaloes. Among these strains, SN-6 secreted cellulase, laccase, and amylase, and significantly inhibited Staphylococcus aureus ATCC25923 and Escherichia coli K99 in vitro. In addition, SN-6 exhibited strong tolerance to artificial gastric juice, intestinal juice, and high temperature. Antibiotic resistance test, virulence gene test, and mouse toxicity test confirmed the safety of SN-6. Further, SN-6 significantly increased the body weight (p < 0.01), affects the intestinal microbiota structure, and alters the metabolomic patterns of Simmental. There was a remarkable difference in the ß diversity of fecal microflora between SN-6 and control groups (p < 0.05). Furthermore, SN-6 significantly increased the abundance of Clostridium_sensu_stricto_1, Bifidobacterium, Blautia, and Cellulolyticum, decreased the relative abundance of Monoglobus and norank_f_Ruminococcacea. Moreover, SN-6 feeding significantly enriched intestinal metabolites (i.e., 3-indoleacrylic acid, kynurenic acid) to maintain intestinal homeostasis. Finally, the microbial and metabolic functional analysis indicated that SN-6 could enhance amino acid metabolism (mainly tryptophan metabolism) and lipid metabolism pathways. Overall, these findings indicated that SN-6 could be used as a probiotic in ruminants.

Regulation of the cecal microbiota community and the fatty liver deposition by the addition of brewers' spent grain to feed of Landes geese.

The effects of brewers' spent grain (BSG) diets on the fatty liver deposition and the cecal microbial community were investigated in a total of 320 healthy 5-day-old Landes geese. These geese were randomly and evenly divided into 4 groups each containing 8 replicates and 10 geese per replicate. These four groups of geese were fed from the rearing stage (days 5-60) to the overfeeding stage (days 61-90). The Landes geese in group C (control) were fed with basal diet (days 5-90); group B fed first with basal diet in the rearing stage and then basal diet + 4% BSG in the overfeeding stage; group F first with basal diet + 4% BSG during the rearing stage and then basal diet in the overfeeding stage; and group W with basal diet + 4% BSG (days 5-90). The results showed that during the rearing stage, the body weight (BW) and the average daily gain (ADG) of Landes geese were significantly increased in groups F and W, while during the overfeeding stage, the liver weights of groups W and B were significantly higher than that of group C. The taxonomic structure of the intestinal microbiota revealed that during the overfeeding period, the relative abundance of Bacteroides in group W was increased compared to group C, while the relative abundances of Escherichia-Shigella and prevotellaceae_Ga6A1_group were decreased. Results of the transcriptomics analysis showed that addition of BSG to Landes geese diets altered the expression of genes involved in PI3K-Akt signaling pathway and sphingolipid metabolism in the liver. Our study provided novel experimental evidence based on the cecal microbiota to support the application of BSG in the regulation of fatty liver deposition by modulating the gut microbiota in Landes geese.

Genome sequence of poultry pathogen Riemerella anatipestifer strain RA-YM.

Riemerella anatipestifer is a Gram-negative, rod-shaped bacterium associated with epizootic infections in poultry. R. anatipestifer strain RA-YM, belonging to the serotype 1 prevalent in China, is a clinically isolated strain with high-level virulence. Here, we report the first genome sequence of this species.

Genome sequence of duck pathogen Mycoplasma anatis strain 1340.

Mycoplasma anatis, a member of the class Mollicutes, is the causative agent of a contagious infectious disease of domestic ducklings, wild birds, and eggs. Increasing reports show that coinfection of M. anatis with Escherichia coli results in substantial economic impacts on the duck farms in China. Here, we announce the first genome sequence of M. anatis.

Activation of the JNK/MAPK Signaling Pathway by TGF-ß1 Enhances Neonatal Fc Receptor Expression and IgG Transcytosis.

The neonatal Fc receptor (FcRn) transports maternal immunoglobulin G (IgG) to the foetus or newborn and protects the IgG from degradation. FcRn is expressed in several porcine tissues and cell types and its expression levels are regulated by immune and inflammatory events. IPEC-J2 cells are porcine intestinal columnar epithelial cells that were isolated from neonatal piglet mid-jejunum. We hypothesized that transforming growth factor ß1 (TGF-ß1) upregulated pFcRn expression in IPEC-J2 cells. To test this hypothesis, we treated IPEC-J2 cells with TGF-ß1 and demonstrated that porcine FcRn (pFcRn) expression was significantly increased. SP600125, a specific mitogen-activated protein kinase (MAPK) inhibitor, reduced TGF-ß1-induced pFcRn expression in IPEC-J2 cells. We performed luciferase reporter assays and showed that the c-JUN sensitive region of the pFcRn promoter gene was located between positions -1215 and -140. The c-JUN sequence, in combination with the pFcRn promoter, regulated luciferase reporter activity in response to TGF-ß1 stimulation. Chromatin immunoprecipitation confirmed that there were three c-JUN binding sites in the pFcRn promoter. Furthermore, in addition to increased pFcRn expression, TGF-ß1 also enhanced IgG transcytosis in IPEC-J2 cells. In summary, our data showed that the modulation of JNK/MAPK signaling by TGF-ß1 was sufficient to upregulate pFcRn expression.

Bacillus amyloliquefaciens TL Downregulates the Ileal Expression of Genes Involved in Immune Responses in Broiler Chickens to Improve Growth Performance.

Bacillus amyloliquefaciens TL promotes broiler chicken performance by improving nutrient absorption and utilization and reducing intestinal inflammation. In this study, RNA-sequencing (RNA-seq)-based transcriptomes of ileal tissues collected from probiotic-fed and control broiler chickens were analyzed to elucidate the effects of the probiotic B. amyloliquefaciens TL, as a feed additive, on the gut immune function. In total, 475 genes were significantly differentially expressed between the ileum of probiotic-fed and control birds. The expression of genes encoding pyruvate kinase, prothymosin-α, and heat stress proteins was high in the ileum of probiotic-fed birds (FPKM > 500), but not in the control group. The gene ontology functional enrichment and pathway enrichment analyses revealed that the uniquely expressed genes in the control group were mostly involved in immune responses, whereas those in the probiotic group were involved in fibroblast growth factor receptor signaling pathways and positive regulation of cell proliferation. Bacillus amyloliquefaciens TL downregulated the expression of certain proinflammatory factors and affected the cytokine-cytokine receptor interaction pathway. Furthermore, B. amyloliquefaciens TL in broiler diets altered the expression of genes involved in immune functions in the ileum. Thus, it might contribute to improved broiler growth by regulating the immune system and reducing intestinal damage in broilers.

Age-Based Variations in the Gut Microbiome of the Shennongjia (Hubei) Golden Snub-Nosed Monkey (Rhinopithecus roxellana hubeiensis).

The gut microbiota represents a source of genetic and metabolic diversity of a complex polymicrobial ecosystem within its host. To investigate age-based variations of the gut microbiota among Shennongjia golden snub-nosed monkeys (Rhinopithecus roxellana hubeiensis), we characterized the microbial species in fecal samples from 18 Shennongjia golden snub-nosed monkeys evenly pooled into 3 aged groups (Group 1, 1-3 years; Group 2, 5-8 years; Group 3, above 12 years) in Shennongjia, Hubei Province, China. Genomic DNA was extracted from fecal samples, and the 16S rRNA gene V4 region was sequenced using the Illumina high-throughput MiSeq platform PE250. A total of 28 microbial phyla were identified in the gut microbiome of these monkeys with the ten most abundant phyla (i.e., Firmicutes, Bacteroidetes, Verrucomicrobia, Spirochaetes, Tenericutes, Proteobacteria, Planctomycetes, Fibrobacteres, Cyanobacteria, and Euryarchaeota). A total of 1,469 (of 16 phyla and 166 genera), 1,381 (of 16 phyla and 157 genera), and 1,931 (of 19 phyla and 190 genera) operational taxonomic units (OTUs) were revealed in Groups 1, 2, and 3, respectively, with Group 3 containing the most diverse groups of OTUs as revealed by the species relative abundance clustering analysis. These results suggest that the gut microbiota in these monkeys maintain a dynamic status, starting from the early developmental stages of life with the species relative abundance increasing with age. This is the first study to comprehensively characterize the gut microbiota and provide valuable information for monitoring the health and nutritional needs of this endangered primate at different ages.

Different Responses of Microbiota across Intestinal Tract to Enterococcus faecium HDRsEf1 and Their Correlation with Inflammation in Weaned Piglets.

Enterococcus faecium HDRsEf1 (HDRsEf1) was identified to reduce the incidence of diarrhea in weaned piglets, but the mechanism has not been elucidated yet. Based on the fact that gut microbiota plays a crucial role in regulating inflammatory responses, the effects of HDRsEf1 on microbiota across the intestinal tract in weaned piglets were investigated. Microbiota from the luminal contents and the mucosa of the ileum, cecum, and colon of HDRsEf1-treated piglets were explored by 16S rRNA sequencing and qPCR. It was demonstrated that microbiota in different gut niches responded specifically to HDRsEf1, with major alterations occurring in the ileum and cecum. The total bacterial load of microbiota in ileal luminal contents and the relative abundance of Escherichia-Shigella in the ileal mucosa was significantly down-regulated by HDRsEf1 administration, while the relative abundance of butyrate-producing bacteria (including Clostridiaceae-1, Rumencoccidae, and Erysipelotrichaceae) in cecal luminal contents was significantly up-regulated. Moreover, the utilization of HDRsEf1 improved intestinal morphological development and reduced the inflammatory response, which were negatively correlated with the relative abundance of Escherichia-Shigella in the ileal mucosa and butyrate-producing bacteria in cecal luminal contents, respectively. Collectively, this study suggests that the administration of HDRsEf1 alters gut microbiota, thereby alleviating inflammation and improving intestinal morphological development in weaned piglets.