This study has evaluated the effect of storage temperature on microbial composition to provide a suitable preparation method for clinical samples. In this study, fresh chicken pulmonary and caecal samples were harvested and set as the control, after which they were stored at different temperatures: −20℃, −80℃, or −196℃ for 7 days. The total ribosomal deoxyribonucleic acid content of the samples was extracted and sequenced to compare differences in microbial composition. At the phylum level, the abundances of Campilobacteria stored at −80°C and −196℃ were lower than in the control and at −20℃. The richness of Proteobacteria in the samples at −20℃ and −80℃ was increased than those in the control. At the genus level, Bacteroides, Rikenellaceas_RC9, Clostrida_vadinBB60, norank_f_norank _o_rhodospirllales, and norank_ f_ Barnesiellaceae accounted for the largest proportion. The abundances of Bacteroides, Helicobacter and Clostridia_vadinBB60 were reduced at −20℃ and −80℃ compared with the control. For the caecal samples, the number of OTUs in control was higher than those stored at −196℃, whereas no difference was observed between the fresh samples and those stored at −20℃ and −80℃. At the phylum level, the abundance of Proteobacteria and unclassified_k_norank_d_bacteria increased in the treated samples compared to the control, whereas the diversity of Firmicute and Bacteroidota was reduced compared with that in the control. Especially, the Cyanobacteria, Campilobacterota, and Synergistota phyla at −80℃ and −196℃ were further reduced than those of the control and at −20℃. At the genus level, Bacteroides, Lactobacillus, Megasphaera, norank_f_ruminococcaceae, Helicobacter, and norank_f_ norank_o_Gastranaerophilales were more abundant in the control samples than in the treated samples. However, the richness of unclassified_k_norank_d_bacteria, Sphingomonas and norank_f_ norank_o_SJA－15 were higher in all of the treated samples than in the control. The pulmonary and caecal samples stored at −80℃ and −196℃ had reduced the bacterial diversities compared with those in the control and at −20℃ as suggested by the linear discriminant analysis. In conclusion, samples of the lung and caecal chyme stored at −20℃ for 7 days can promote the colonisation of microbiota, leading to inaccurate sequencing data. Samples stored at −80℃ and −196℃can decrease the abundance of the microbial composition.

Salmonellosis remains a globally prevalent zoonotic disease. Conventional antibiotic therapy for salmonellosis carries risks such as antimicrobial resistance and disruption of intestinal microbiota. Extensive research has demonstrated that probiotics, including lactic acid bacteria (LAB), can serve as an alternative to antibiotics. In view of the fact that host-origin probiotics possess superior functions, a canine-derived Lactiplantibacillus plantarum strain with efficacy against Salmonella was isolated, screened, and identified, and was named GHR. Biological characterization assays revealed that GHR possesses excellent acid tolerance, heat tolerance, and bile salt tolerance. Colonization assays demonstrated that GHR effectively colonizes the murine small intestine. By establishing GHR prophylactic and therapeutic mouse models of salmonellosis, followed by clinical symptom analysis, organ coefficient evaluation, and histopathological examination, we confirmed that GHR exhibits strong preventive effects against salmonellosis. This study successfully isolated and purified a canine-derived Lactiplantibacillus plantarum strain capable of effectively preventing murine salmonellosis, which provides a novel alternative approach for the prevention and treatment of salmonellosis in dogs and supports the broader application of canine-derived LAB with empirical data.

IntroductionThe present study aimed to explore the genetic profile and annotate the metabolic profile of chicken cecum-derived B. subtilis YB-114246, which has been used in laying hens.MethodsThe complete genome of B. subtilis YB-114246 was analyzed and its probiotic metabolic profile was identified using genomic and metabolomic assays.Results and discussionB. subtilis YB-114246 possessed a chromosome containing 4,673,022 bp with a G+C content of 55.03%. The complete genetic sequence indicated that > 40% of the genes were coding sequences related to nutritional transportation and metabolism. B. subtilis YB-114246 harboring more unique genetic clusters played a role in the metabolism of macro molecular substances and synthesized more secondary metabolites. These genes are involved in glycan metabolism, amino acid and vitamin biosynthesis, and they also contribute to nutrient absorption and utilization in chickens. In this study, nonspecific virulence factor-related genes were identified in the genome of B. subtilis YB-114246. The metabolic profiles indicated that the primary functional substances were amino acids, phospholipids, eicosanoids, nucleotides, polyketides, and non-ribosomal peptides. The activities of digestive enzymes cellulase, amylase, protease, and lipase in fermented liquid of B. subtilis YB-114246 were 33.49, 1.23, 9.01, and 0.49 U/mL respectively. Correlation analysis between laying performance and metabolites showed that riboflavin, p-acetaminobenzoic acid, and 6-hydroxyhexanoic acid exhibited promoting effects. Riboflavin synthesized and secreted by B. subtilis YB-114246 reached 6.76 μg/L. The synthesis pathway predicted using the Kyoto Encyclopedia of Genes and Genomes (KEGG) database originates from the purine metabolism and is involved in the pentose phosphate pathway in ribosomes. The utilization and recycling patterns of riboflavin were modeled, revealing a reciprocal relationship with the host.ConclusionOur findings revealed that the abundant nutritional genes and the production of functional metabolites by B. subtilis YB-114246 supplementation may enhance the laying performance of aged hens by improving digestive abilities.

The aim of this study was to elucidate the intrinsic microbiota residing in the heart and liver, which was enriched with Ligilactobacillus salivarius supplementation and its roles in defending anti-oxidation of heat stress. The specific pathogen free (SPF) mice were employed to perform the study. Genomic sequencing showed that the intrinsic microbes in the heart and liver of SPF mice, which were primarily of the genera Burkholderia and Ralstonia, functioned in organic metabolism, environmental information processing, cellular processes, and genetic information processing. Lactobacillus sp. were found in the liver but not in the heart. The heart had a lower bacterial abundance than the liver. A culturomic assay of the heart flushing liquid indicated that the dominant species of bacteria were Ralstonia pickettii, Ralstonia sp._3PA37C10, Ralstonia insidiosa, Burkholderia lata, unclassified _g_ Ralstonia, and unclassified _p_ Pseudomonadota. Intrinsic bacteria exist in the heart due to their inhibitory action against pathogenic Escherichia coli. After, the mice were supplemented with Ligilactobacillus salivarius to optimize the microbiota levels. The dominant bacterial phyla in the liver and heart were Bacillota, Bacteroidota, Pseudomonadota, Thermodesulfobacteriota, andActinomycetota, which comprised 98.2% of total bacteria. The genus Lactobacillus was also abundant. Core bacteria such as Lactobacillus reuteri are translocated from the intestine to the heart and liver. The enriched bacterial composition up-regulated anti-oxidation capacities in the heart and liver. The levels of reactive oxygen species and superoxide dismutase (SOD) were significantly improved compared to those in control (P < 0.01). In conclusion, intrinsic bacteria present in the heart and liver alleviate infection by pathogens, environmental and genetic information processing, and cellular processes during heat stress exposure. Diet with Ligilactobacillus salivarius supplementation regulated the translocation of core bacteria to the heart and liver, improved bacterial composition, and induced a higher anti-oxidative capacity under heat stress.

Objective Lactobacillus salivarius is a probiotic bacteria strain in human and animal diets. The administration of probiotics to weaned piglets may improve their growth by optimizing the gastrointestinal bacterial composition. To further investigate the effect of bacterial communication between the gastrointestinal tract and lungs on bodily immunity, we reared weaned piglets in a low-ammonia gas environment. L. salivarius was supplemented to explore its effects on pulmonary immunity and its potential for bacterial translocation. Results One hundred sixty weaned piglets were allocated to four groups: L. salivarius-supplemented, L. reuteri-supplemented, control, and antibiotic drug (aureomycin)-supplemented. The feeding duration was 28 d. The body weights of piglets administered a strain of Lactobacillus were better than those of the control (P < 0.01). The transcription level of immune factors interleukin 2 (IL-2), IL-4, interferon α (IFN-α), and tumor necrosis factor α (TNF-α) in cells of the ileum and lung was significantly higher (P < 0.01). Lung and ileal mucus tissues were isolated to sequence the bacterial composition, which suggested a higher richness in the lungs at the phylum level, which was not significant in the ileum. Functional bacteria were more abundant in the ileum and lungs. The proportion of the genera of Lactobacillus, Prevotella, Actinobacillus, and Prevotellaceae_ NK3B31_group increased in two tissues, and a lower ratio of Streptococcus, Escherichia-Shigella, and mycoplasma was detected. The correlation between the microbial genus composition and the levels of immune factors suggests that the abundance of Lactobacillus plays the same positive role in the lungs and ileum. Mycoplasmas play a negative role in ileal and pulmonary immunity. More Lactobacillus reuteri and anaerobic probiotic bacteria were detected in the lungs. Conclusion The colonization of Lactobacillus salivarius and Lactobacillus reuteri in the membrane of the ileum optimized the ileal microbial composition, enrolled other probiotic bacteria translating to the lung, improved the abundance of pulmonary microbiota, and enhanced immunity after exposure to low concentrations of ammonia.

BACKGROUND:As substitutes for antibiotics, probiotic bacteria protect against digestive infections caused by pathogenic bacteria. Ligilactobacillus salivarius is a species of native lactobacillus found in both humans and animals. Herein, a swine-derived Ligilactobacillus salivarius was isolated and shown to colonize the ileal mucous membrane, thereby promoting nutritional digestion, absorption, and immunity. To evaluate its probiotic role, the entire genome was sequenced, the genetic information was annotated, and the metabolic information was analyzed.RESULTS:The phylogenetic relationship indicated that the bacteria was closer to L. salivarius MT573555.1 and MT585431.1. Functional genes included transporters, membrane proteins, enzymes, heavy metal resistance proteins, and putative proteins; metabolism-related genes were the most abundant. The six types of metabolic pathways secreted by L. salivarius were mainly composed of secretory transmembrane proteins and peptides. The secretory proteins of L. salivarius were digestive enzymes, functional proteins that regulate apoptosis, antibodies, and hormones. Non-targeted metabolomic analysis of L. salivarius metabolites suggested that ceramide, pyrrolidone- 5- carboxylic acid, N2-acetyl-L-ornithine, 2-ethyl-2-hydroxybutyric acid, N-lactoyl-phenylalanine, and 12 others were involved in antioxidation, repair of the cellular membrane, anticonvulsant, hypnosis, and appetite inhibition. Metabolites of clavaminic acid, antibiotic X14889C, and five other types of bacteriocins were identified, namely phenyllactic acid, janthitrem G, 13-demethyl tacrolimus, medinoside E, and tertonasin. The adherence and antioxidation of L. salivarius were also predicted. No virulence genes were found.CONCLUSION:The main probiotic properties of L. salivarius were identified using genomic, metabonomic, and biochemical assays, which are beneficial for porcine feeding. Our results provided deeper insights into the probiotic effects of L. salivarius.

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

通过体外、体内两个途径研究饲用粪肠球菌、枯草芽胞杆菌对禽大肠杆菌的抑制作用进行研究.体外采用共培养检测其对禽大肠杆菌的抑制作用,并用牛津杯法检测其抑菌效果;体内将粪肠球菌、枯草芽胞杆菌制成复合菌剂饲喂黄羽肉鸡,检测肉鸡血清抗氧化力、盲肠乳酸菌、总芽孢杆菌和大肠杆菌活菌数量来确定其对大肠杆菌的抵制作用.结果表明,体外在共培养 12h 后,粪肠球菌显著地降低了大肠杆菌的数量,大肠杆菌数量由1×109 CFU/ml降低至 2×105 CFU/ml,至 36h后,培养液中未检测出大肠杆菌.枯草芽孢杆菌具有抑制大肠杆菌能力,在培养 24h后,大肠杆菌数量由 1×109 CFU/ml降低至 1×105 CFU/ml,至 36h后,培养液中的大肠杆菌数量降低到 2×103 CFU/ml,至 48h后,培养液中检测不出大肠杆菌数.牛津杯法检测抑菌效果表明,在伊红美兰琼脂培养基中,粪肠球菌、枯草芽胞杆菌发酵滤液可抑制禽大肠杆菌生长,出现抑菌圈,直径分别为20.12 mm和 15.54 mm.养殖试验结果表明,黄羽肉鸡按 2×106 CFU/g 的添加量饲喂复合菌后,机体抗氧化能力显著增强,盲肠菌群中乳酸菌数量和总芽孢杆菌数量显著提高,大肠杆菌数量显著下降.粪肠球菌、枯草芽胞杆菌能显著抑制禽源大肠杆菌,可作为饲料添加剂用于肉鸡养殖.

Background: Storage conditions are as an important influence on accurate analysis of deoxyribonucleic acid based microbial communities in metagenomic studies. In this study, fresh chicken pulmonary and cecal samples were prepared and stored in −20 °C, −80°C and liquid nitrogen (−147°C) for 7days. The total 16 ribosomal deoxyribonucleic acid was extracted and measured with next generated sequencing of the V3-4 region gene to compare frequently-used storage conditions on the quality and composition of the fecal microbial community. Results: Total microbial composition in fresh pulmonary samples were more abundant than those stored in -80°C for 7days in total OUT number, and the composition at phylum level were richer than those stored in -20 °C, -80°C and -147°C. The phylum of campilobacteria , proteobacteria , bacteroidota , and actinobacteriota were significant higher. Result of α diversity showed there were no differences on microbial number at genus level. While, abundances of microbial composition varied, the mainly distinct genus bacteroides , rikenellaceas _ RC9 , clostrida _ vadinBB60 , norank_f_norank_o_ rhodospirllales , norank_f_ barnesiellaceae . Results of microbial composition in fresh cecal chyme suggested that the genus of bacteroides , megasphaera , norank_f_ ruminococcaceae , helicobacter , and norank_f_ norank_o_gastranaerophilales are richer than all other groups, while the genus of sphingomonas , norank_f_ norank_o_ SJA－15 were lower than those of others. The OTU number in fresh cecal chyme was higher than those stored in -147°C, while there were no differences with -20°C and -80°C. Also, microbial composition at phylum level were no significant differences between fresh and others in cecal chyme. Number of differential microbial in both pulmonary and cecal samples stored in -80°C and -147°C were little compared with those in fresh and -20°C suggested with LEfSe linear discriminant analysis. Conclusion: Samples of lung and cecal chyme for 16S r DNA sequencing stored in -20°C for 7 days can induce to microbial colonization, which were not accurate in interpreting data. In -80°C and -147°C introduce declined tendencies in post-collection compared with fresh samples.

通过检测金针菇菌渣固态发酵后的品质变化,评价发酵效果;同时探究4种不同贮藏条件对发酵品活菌和霉变的影响,筛选出最佳贮藏方式.以金针菇菌渣为原料,添加乳酸菌和枯草芽孢杆菌菌种,固态发酵完成后,检测发酵前后样品中消化酶活性、益生菌活菌数量、霉菌数量、磷元素含量、水分、黄霉菌毒素B1含量;进行袋装贮藏试验,比较不同贮藏条件下,不同贮藏时间段,发酵品活菌和发霉情况的动态变化.结果表明:金针菇菌渣经固态发酵后蛋白酶、脂肪酶、α-淀粉酶、β-淀粉酶活力水平显著升高,分别达到165.19、10.68、472.09、215.09 U/g,且水分降低至46.11％,益生菌活菌数增多,达到109 CFU/g,霉菌数减少至106 CFU/g,磷元素含量呈下降趋势.透气、温度、光照3个因素对金针菇菌渣发酵产品的贮藏品质均有影响.室温、透气、避光贮藏15 d和1个月后,益生菌活菌数量显著高于其他组,发霉较轻,黄曲霉毒素B1含量处于安全范围;低温、不透气、避光贮藏时,益生菌和霉菌数量显著减少,黄曲霉毒素B1含量也最低.经固态发酵后,金针菇菌渣品质显著改善,贮藏方式为室温、避光、透气保存,可有效贮藏1个月.

Abundant microbiota resides in the organs of the body, which utilize the nutrition and form a reciprocal relationship with the host. The composition of these microbiota changes under different pathological conditions, particularly in response to stress and digestive diseases, making the microbial composition and health of the hosts body interdependent. Probiotics are living microorganisms that have demonstrated beneficial effects on physical health and as such are used as supplements to ameliorate symptoms of various digestive diseases by optimizing microbial composition of the gut and restore digestive balance. However, the supplementary effect does not achieve the expected result. Therefore, a targeted screening strategy on probiotic bacteria is crucial, owing to the presence of several bacterial strains. Core bacteria work effectively in maintaining microbiological homeostasis and stabilization in the gastrointestinal tract. Some of the core bacteria can be inherited and acquired from maternal pregnancy and delivery; others can be acquired from contact with the mother, feces, and the environment. Knowing the genera and functions of the core bacteria could be vital in the isolation and selection of probiotic bacteria for supplementation. In addition, other supporting strains of probiotic bacteria are also needed. A comprehensive strategy for mining both core and supporting bacteria before its clinical use is needed. Using metagenomics or other methods of estimation to discern the typically differentiated strains of bacteria is another important strategy to treat dysbiosis. Hence, these two factors are significant to carry out targeted isolation and selection of the functional strains to compose the resulting probiotic preparation for application in both research and clinical use. In conclusion, precise probiotic supplementation, by screening abundant strains of bacteria and isolating specific probiotic strains, could rapidly establish the core microbiota needed to confer resilience, particularly in bacterial dysfunctional diseases. This approach can help identify distinct bacteria which can be used to improve supplementation therapies.

Here, a Selenium-enriched Bacillus subtilis (SEBS) strain was generated and supplemented to broiler chickens' diet, and the impact in ileum bacterial microbiome, immunity and body weight were assessed. In a nutshell, five hundred 1-old old chicken were randomly divided into five groups: control, inorganic Se, Bacillus subtilis (B. subtilis), SEBS, and antibiotic, and colonization with B. subtilis and SEBS in the gastrointestinal tract (GIT) were measured by fluorescence in situ hybridization (FISH) assay and quantitative real-time polymerase chain reaction (qPCR). In summary, Chicks fed SEBS or B. subtilis had higher body weight than the control chicks or those given inorganic Se. SEBS colonized in distal segments of the ileum improved bacterial diversity, reduced the endogenous pathogen burden and increased the number of Lactobacillus sp. in the ileal mucous membrane. Species of unclassified Lachnospiraceae, uncultured Anaerosporobacter, Peptococcus, Lactobacillus salivarius, and Ruminococcaceae_UCG-014, and unclassified Butyricicoccus in the ileal mucous membrane played a key role in promoting immunity. Inorganic Se supplementation also improved bacterial composition of ileal mucous membranes, but to a less extent. In conclusion, SEBS improved performance and immunity of broiler chickens through colonization and modulation of the ileal mucous membrane microbiome.

Jiajun Yang (  yjj1984112@outlook.com ) School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry Jiang Wang School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry Kehe Huang Nanjing Agricultural University College of Veterinary Medicine Qingxin Liu School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agricultrue and Forestry Xiaozhou Xu School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry Guofang Liu School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry Hao Zhang College of Animal Science and Technology, Chinese Agricultural University Mengling Zhu School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry

为研究抗菌肽在蛋鸡生产中对抗生素的替代效果,试验选取37周龄480只龙华草鸡型蛋鸡,随机分为4组,每组120只,设4个重复,每个重复为30只,对照组饲喂基础日粮,抗生素组在基础日粮中添加8％黄霉素62.5 g/t,试验组分别在基础日粮中添加抗菌肽100、200 g/t.预试期7 d,饲喂基础日粮,试验期60 d.结果表明:抗菌肽对蛋品质无明显作用,但试验1、2组产蛋率比对照组分别提高了12.5％和12.2％(P<0.01),,料蛋比分别下降8.6％和4.6％(P<0.01),同时试验1、2组血清中IgG含量比对照组分别提高45.8％和55.8％(P<0.01),试验2组血清的T-AOC较对照组提高18.5％(P<0.01),试验1、2组血清中BUN的含量分别较对照组降低35.9％、49.5％(P<0.01).综上,抗菌肽能提高蛋鸡产蛋率,降低料蛋比,并提高机体的免疫及抗氧化能力.

Background: Selenium-enriched Bacillus subtilis (SEBS) was made to add into the diets of broiler chickens to observe combined effects on the bacterial composition and immunity of ileum through its colonization on the site of intestinal mucous membrane to improve the body growth and immunity. Five hundred 1-d-old chickens were divided into five groups randomly: Control, inorganic Se, Bacillus subtilis ( B. subtilis ), SEBS, and antibiotic. The feed duration was 42 days (d). Growth performance was recorded and calculated. The strain of B. subtilis and SEBS colonizing in the gastrointestinal tract (GIT) were investigated using fluorescence in situ hybridization (FISH) assay and quantitative real-time polymerase chain reaction (qPCR). The V3-V4 hypervariable regions of the bacterial region of 16S rRNA gene were sequenced. Results: After 42 d of treatment, chicks feed SEBS or Bacillus subtilis had higher body weights than the control chicks or those given inorganic Se. SEBS colonized in distal segments of the ileum improved bacterial diversity, while reducing the number of endogenous pathogen and increasing the number of Lactobacillus sp. in ileal mucous membranes. Species of unclassified Lachnospiraceae , uncultured Anaerosporobacter , Peptococcus , Lactobacillus salivarius , and Ruminococcaceae_UCG-014 , and unclassified Butyricicoccus in ileal mucous membranes played an important role in promoting immunity, such as tumor necrosis factor-α and interferon-β through spearman’s analysis. Dietary supplementary Se also improved bacterial composition of ileal mucous membranes. SEBS colonization in the ileal mucous membrane optimized bacterial composition, more enhanced the abundances of metabolic and immune genes on body growth and immunity. Conclusions: SEBS improved body growth performance and immunity of broiler chickens through colonization in the ileal mucous membrane and modified ileal bacterial composition.

The aim of this study was to investigate the effects and potential signaling pathway of selenium-enriched Bacillus subtilis (SEBS) on beta defensin 1 (BD1) expression in chicken intestine. Chinese Huainan Partridge chickens (500 individuals) were randomly allocated into five groups, including control, inorganic Se, B. subtilis, SEBS, and a mixture of Se and B. subtilis (Se-BS). After 56 d of feeding, chicken ileal mucous membranes were harvested to detect differences in expression of BD1. The results indicated that BD1 was produced in intestinal crypt cells and secreted into the lumen through the villi brush border. BD1 was up-regulated in distal ileum segments colonized by SEBS and B. subtilis. Chicken primary intestinal crypt cells were cultured and grouped into control, inorganic Se, B. subtilis, SEBS, and Se-BS treatments to identify the receptor of B. subtilis. Results indicated that B. subtilis and SEBS were recognized by toll-like receptor 2 (TLR2), stimulating the NF-κB1 signaling pathway to increase expression of BD-1, which was further enhanced when combined with Se. Pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 were up-regulated with B. subtilis supplementation, and inhibited under the action of Se. In conclusion, B. subtilis and SEBS were recognized by the TLR2 receptor in the ileal mucous membrane, which activated the TLR2-MyD88-NF-κB1 signaling pathway to upregulate BD1 expression. In addition, Se enhanced recognition of B. subtilis and reduced levels of pro-inflammatory factors caused by estrogenic B. subtilis supplementation.

试验研究益生菌发酵饲料对仔猪生长性能、血清免疫指标及肠道菌群的影响.选择体重15 kg左右、日龄相近的健康杜长大三元杂种仔猪80头(公母比1:1),随机分为抗生素组和益生菌发酵饲料组,每组设4个重复,每个重复10头,公母各半,单圈饲养.预试期6 d,正试期33 d.抗生素组在基础饲粮中添加15％金霉素500 g/t、20％土霉素钙1000 g/t,益生菌发酵饲料组是90％基础饲粮+10％益生菌发酵饲料.试验结果显示:1)与抗生素组相比,益生菌发酵饲料组平均日增重提高18.20％(P<0.01),料重比下降14.89％(P<0.01);2)与抗生素组相比,益生菌发酵饲料组中总抗氧化能力(T-AOC)提高141.44％(P<0.01),谷丙转氨酶下降37.34％(P<0.05);血糖、总蛋白、尿素氮、谷草转氨酶两组差异都不显著(P>0.05);3)与抗生素组相比,益生菌发酵饲料组中IgA提高118.28％(P<0.01),IgG、IgM两组差异都不显著(P>0.05);4)与抗生素组相比,益生菌发酵饲料组中乳酸菌含量提高5.13％(P>0.05),大肠杆菌含量下降15.48％(P<0.05).综上所述,在生猪饲粮中添加益生菌发酵饲料替代抗生素,使猪的生长性能有显著提高,总抗氧化能力显著提高,免疫指标显著提高,肠道菌群结构显著改善.

Here, a Selenium-enriched Bacillus subtilis (SEBS) strain was generated and supplemented to broiler chickens’ diet, and the impact in ileum bacterial microbiome, immunity and body weight were assessed. In a nutshell, five hundred 1-old old chicken were randomly divided into five groups: control, inorganic Se, Bacillus subtilis ( B. subtilis ), SEBS, and antibiotic, and colonization with B. subtilis and SEBS in the gastrointestinal tract (GIT) were measured by fluorescence in situ hybridization (FISH) assay and quantitative real-time polymerase chain reaction (qPCR). In summary, Chicks fed SEBS or B. subtilis had higher body weight than the control chicks or those given inorganic Se. SEBS colonized in distal segments of the ileum improved bacterial diversity, reduced the endogenous pathogen burden and increased the number of Lactobacillus sp. in the ileal mucous membrane. Species of unclassified Lachnospiraceae , uncultured Anaerosporobacter , Peptococcus , Lactobacillus salivarius , and Ruminococcaceae_UCG-014 , and unclassified Butyricicoccus in the ileal mucous membrane played a key role in promoting immunity. Inorganic Se supplementation also improved bacterial composition of ileal mucous membranes, but to a less extent. In conclusion, SEBS improved performance and immunity of broiler chickens through colonization and modulation of the ileal mucous membrane microbiome.

试验研究发酵中草药添加剂对仔猪生长性能、血清免疫指标及肠道菌群的影响.选择体重15 kg左右、日龄相近的健康杜长大三元杂种断奶仔猪80头(公母比1∶1),随机分为抗生素组和发酵中草药添加剂组,每组设4个重复,每个重复10头,公母各半,单圈饲养.预试期6 d,试验期33 d.抗生素组在基础饲粮中添加15％金霉素500 g/t、20％土霉素钙1000 g/t,发酵中草药添加剂组是在基础饲粮中添加2％发酵中草药添加剂.试验结果显示:1)与抗生素对照组相比,发酵中草药添加剂组平均日增重上升10.43％(P<0.01),料重比下降9.04％(P<0.01).2)与抗生素对照组相比,发酵中草药添加剂组总抗氧化能力上升76.58％(P<0.05),总蛋白上升9.37％(P<0.05),血糖、尿素氮、谷草转氨酶、谷丙转氨酶两组差异都不显著(P>0.05).3)与抗生素对照组相比,发酵中草药添加剂组IgM上升79.02％(P<0.01),IgA、IgG两组差异都不显著(P>0.05).4)与抗生素对照组相比,发酵中草药添加剂组乳酸菌含量上升6.25％(P>0.05),大肠杆菌含量下降9.81％(P>0.05).综上所述,与抗生素对照组相比,发酵中草药添加剂组使猪的生长性能、总抗氧化能力和免疫指标显著提高,肠道菌群结构有一定程度的改善.