Dietary Lactobacillus fermentum and Bacillus coagulans Supplementation Modulates Intestinal Immunity and Microbiota of Broiler Chickens Challenged by Clostridium perfringens

Effects of Adding Bacillus coagulans BCH0 to the Diet on Growth Performance, Tissue Structures, and Gut Microbiota in Broilers

Studies demonstrated that Bacillus coagulans (B. coagulans) as a dietary additive enhanced broiler growth performance, yet its mechanisms of action modulation remained unclear. Therefore, this study investigated effects of dietary B. coagulans BCH0 (1 × 109 CFU/kg) on growth performance, intestinal morphology, gut microbiota, and ileal transcriptomics in Arbor Acres broilers using a completely randomized design. A total of 200 one-day-old broilers were allocated to control (Con, basal diet) and experimental (BCH0, basal diet + 1 × 109 CFU/kg B. coagulans BCH0) groups (10 replicates/group, 10 birds/replicate) over a 42-day trial. The results revealed that BCH0 significantly increased body weights (BW) at 21 and 42 days (p < 0.05), improved the average daily gain (ADG) during the starter (1-21 days) and overall phases (1-42 days), and reduced the ratio of feed intake to body weight gain (F/G) across all phases (p < 0.05). Duodenal morphology analysis indicated a BCH0 elevated villus height (+16.9%, p < 0.01) and villus height/crypt depth (V/C) (p < 0.01) and no significant differences in crypt depth (p = 0.46). In the ileum, the BCH0 group exhibited a significantly greater villus height (p < 0.01), crypt depth (p < 0.05), and V/C (p < 0.05) than the Con group. Microbiota analysis revealed no significant differences in α-diversity or β-diversity, but phylum-level shifts involved an increase in Firmicutes and a reduction in Actinobacteriota in the BCH0 group. At the genus level, dominance shifted from Romboutsia (Control group) to Lactobacillus (BCH0 group), accompanied by marked reductions in Turicibacter, Ldatus_arthromitus, and Rothia. Ileal transcriptomics identified 605 differentially expressed genes, with KEGG enrichment highlighting activated nutrient assimilation pathways (p < 0.05), including carbohydrate, mineral, fat, and protein digestion/absorption. These findings collectively demonstrated that B. coagulans BCH0 enhanced broiler growth through the synergistic modulation of beneficial microbiota, the upregulation of nutrient metabolism genes, and intestinal architectural optimization, supporting its role as a sustainable microbial additive for enhancing poultry productivity and gut health.

Effects of Bacillus coagulans on Growth Performance, Digestive Enzyme Activity, and Intestinal Microbiota of the Juvenile Fourfinger Threadfin (Eleutheronema tetradactylum)

The effects of Bacillus coagulans (BC) T-21 on growth performance, intestinal digestive enzyme activity, intestinal morphology, and intestinal microbiota of juvenile fourfinger threadfin (Eleutheronema tetradactylum) were investigated in the present study. Healthy juvenile E. tetradactylum with an initial body weight of 4.2 ± 0.5 g were fed a basal diet sprayed with 1 × 108 cfu/g B. coagulans for eight weeks, and the growth parameters, intestinal digestive enzyme activities, HE-stained intestinal sections, and intestinal microbiota of the juvenile fish were measured. The differences in the feed conversion ratio between the experimental and control groups (fed the basal diet) were extremely significant (p < 0.01), whereas the differences in weight gain rate, specific growth rate, survival rate, and condition factor were significant (p < 0.05). In the experimental group, trypsin and amylase activities decreased significantly, whereas there were no significant differences in lipase activity between the two groups. Compared to the control group, the height of the intestinal villi was greater. No significant differences were observed in the diversity of intestinal microbiota and microbial species at the genus level (p > 0.05). Based on the function prediction analysis, the count values for the glycan biosynthesis, metabolism, and digestive system pathways were significantly increased in the experimental group (p < 0.05). However, there were no significant differences in the counts of other functional pathways (p > 0.05). These results indicate that dietary B. coagulans supplementation is effective in promoting the growth performance and intestinal health of juvenile E. tetradactylum.

A Two Bacteriocinogenic Ligilactobacillus Strain Association Inhibits Growth, Adhesion, and Invasion of Salmonella in a Simulated Chicken Gut Environment

In this study, we aimed to develop a protective probiotic coculture to inhibit the growth of Salmonella enterica serovar Typhimurium in the simulated chicken gut environment. Bacterial strains were isolated from the digestive mucosa of broilers and screened in vitro against Salmonella Typhimurium ATCC 14028. A biocompatibility coculture test was performed, which identified two biocompatible strains, Ligilactobacillus salivarius UO.C109 and Ligilactobacillus saerimneri UO.C121 with high inhibitory activity against Salmonella. The cell-free supernatant (CFS) of the selected isolates exhibited dose-dependent effects, and the inhibitory agents were confirmed to be proteinaceous by enzymatic and thermal treatments. Proteome and genome analyses revealed the presence of known bacteriocins in the CFS of L. salivarius UO.C109, but unknown for L. saerimneri UO.C121. The addition of these selected probiotic candidates altered the bacterial community structure, increased the diversity of the chicken gut microbiota challenged with Salmonella, and significantly reduced the abundances of Enterobacteriaceae, Parasutterlla, Phascolarctobacterium, Enterococcus, and Megamonas. It also modulated microbiome production of short-chain fatty acids (SCFAs) with increased levels of acetic and propionic acids after 12 and 24 h of incubation compared to the microbiome challenged with S. Typhimurium. Furthermore, the selected probiotic candidates reduced the adhesion and invasion of Salmonella to Caco-2 cells by 37-39% and 51%, respectively, after 3 h of incubation, compared to the control. These results suggest that the developed coculture probiotic strains has protective activity and could be an effective strategy to control Salmonella infections in poultry.

Bacillus coagulans MF-06 alleviates intestinal mucosal barrier from damage in chicks infected with Salmonella pullorum via activating the Wnt/β-catenin pathway

Introduction

This study aimed to assess the protective efficacy of Bacillus coagulans MF-06 as a potential alternative to antibiotics in mitigating intestinal mucosal damage in chicks infected with Salmonella pullorum.

Methods

A total of 150 one-day-old SPF chicks were selected and randomly divided into five groups: control group (CK), probiotics group (EM), probiotics treatment group (PT), antibiotic treatment group (AT), Salmonella pullorum group (SI), CK, AT and SI groups were fed a basal diet, EM and PT groups were fed a basal diet supplemented with 1.0 × 108 CFU/g Bacillus coagulans; PT, AT and SI groups were gavaged with 1.0 × 109 CFU/0.5 mL Salmonella pullorum at 7 days of age; AT group were fed with 0.375 g/kg neomycin sulfate in the basal diet from days 7-14.

Results

Subsequently, the study evaluated alterations in growth performance, the integrity of the intestinal mucosal barrier, cytokines associated with the Wnt/β-catenin signaling pathway, and gut microbiota composition. The results revealed that the administration of Bacillus coagulans MF-06 significantly reduced the feed conversion ratio of chicks (p < 0.05), and significantly increased the average daily weight gain and average daily feed intake in chicks challenged with Salmonella Pullorum (p < 0.05). Furthermore, Bacillus coagulans MF-06 treatment diminished the presence of Salmonella pullorum colonies in the intestinal tract. Additionally, the administration of Bacillus coagulans MF-06 restored levels of (Diamine oxidase) DAO and (D-lactic acid) D-LA levels, as well as the levels of tight junction protein, including TJP1, CLDN1, CLDN2, Occludin, and MUC2 (p < 0.05). The study noted a significant decrease in cell apoptosis (p < 0.05) and a significant increase in the expression of Proliferating Cell Nuclear Antigen (PCNA) and v-myc avian myelocytomatosis viral oncogene homolog (C-MYC) (p < 0.05), which activated the Wnt/β-catenin signaling pathway. Analysis through 16S rRNA sequencing revealed that the intake of Bacillus coagulans MF-06 led to a significant decrease in the relative abundance of Lachnoclostridium, Shuttleworthia, and unidentified-Eggerthellaceae (p < 0.05).

Discussion

Collectively, the Bacillus coagulans MF-06 may provide a protective effect against Salmonella pullorum infection in chicks by enhancing growth performance, strengthening the integrity of the intestinal mucosal barrier, and stabilizing the gut microbiota.

Soybean oil induces neuroinflammatory response through brain-gut axis under high-fat diet

Neuroinflammation is considered the principal pathogenic mechanism underlying neurodegenerative diseases, and the incidence of brain disorders is closely linked to dietary fat consumption and intestinal health. To investigate this relationship, 60 8-week-old C57BL/6J mice were subjected to a 20-week dietary intervention, wherein they were fed lard and soybean oil, each at 15% and 35% fat energy. At a dietary fat energy level of 35%, inflammation was observed in both the soybean oil and lard groups. Nevertheless, inflammation was more pronounced in the mice that were administered soybean oil. The process by which nerve cell structure is compromised, inflammatory factors are upregulated, brain antioxidant capacity is diminished, and the TLR4/MyD88/NF-κB p65 inflammatory pathway is activated resulting in damage to the brain-gut barrier. This, in turn, leads to a reduction in the abundance of Akkermansia and unclassified_f_Lachnospiraceae, as well as an increase in Dubosiella abundance, ultimately resulting in brain inflammation and damage. These results suggested that soybean oil induces more severe neuroinflammation compared to lard. Our study demonstrated that, at a dietary fat energy level of 35%, compared to soybean oil, lard could be the healthier option, the outcomes would help provide a reference basis for the selection of residents' daily dietary oil.

Progress of research and application of Heyndrickxia coagulans (Bacillus coagulans) as probiotic bacteria

Probiotics are defined as living or dead bacteria and their byproducts that maintain the balance of the intestinal microbiome. They are non-toxic, non-pathogenic, and do not release any toxins either within or outside the body. Adequate consumption of probiotics can enhance metabolite production, increase immunity, maintain a balanced intestinal flora, and stimulate growth. Probiotics do not have negative antibiotic effects and help maintain the natural flora in animals in a balanced state or prevent dysbacteriosis. Heyndrickxia coagulans (H. coagulans) is a novel probiotic species that is gradually being used for the improvement of human health. Compared to commonly used probiotic lactic acid bacteria, H. coagulans can produce spores, which provide the species with high resistance to adverse conditions. Even though they are transient residents of the gut, beneficial bacteria can have a significant impact on the microbiota because they can outnumber harmful germs, and vice versa. This article discusses the probiotic mechanisms of H. coagulans and outlines the requirements for a substance to be classified as a probiotic. It also addresses how to assess strains that have recently been discovered to possess probiotic properties.

Effects of dietary Nisin on growth performance, immune function, and gut health of broilers challenged by Clostridium perfringens

Nisin (Ni) is a polypeptide bacteriocin produced by lactic streptococci (probiotics) that can inhibit the majority of gram-positive bacteria, and improve the growth performance of broilers, and exert antioxidative and anti-inflammatory properties. The present study investigated the potential preventive effect of Nisin on necrotic enteritis induced by Clostridium perfringens (Cp) challenge. A total of 288 Arbor Acres broiler chickens of 1-d-olds were allocated using 2 × 2 factorial arrangement into four groups with six replicates (12 chickens per replicate), including: (1) control group (Con, basal diet), (2) Cp challenge group (Cp, basal diet + 1.0 × 108 CFU/mL Cp), (3) Ni group (Ni, basal diet + 100 mg/kg Ni), and (4) Ni + Cp group (Ni + Cp, basal diet + 100 mg/kg Ni + 1.0 × 108 CFU/mL Cp). The results showed that Cp challenge decreased the average daily gain (ADG) of days 15 to 21 (P<0.05) and increased interleukin-6 (IL-6) content in the serum (P < 0.05), as well as a significant reduction in villus height (VH) and the ratio of VH to crypt depth (VCR) (P<0.05) and a significant increase in crypt depth (CD) of jejunum (P<0.05). Furthermore, the mRNA expressions of Occludin and Claudin-1 were downregulated (P<0.05), while the mRNA expressions of Caspase3, Caspase9, Bax, and Bax/Bcl-2 were upregulated (P<0.05) in the jejunum. However, the inclusion of dietary Ni supplementation significantly improved body weight (BW) on days 21 and 28, ADG of days 15 to 21 (P<0.05), decreased CD in the jejunum, and reduced tumor necrosis factor-α (TNF-α) content in the serum (P<0.05). Ni addition upregulated the mRNA levels of Claudin-1 expression and downregulated the mRNA expression levels of Caspase9 in the jejunum (P<0.05). Moreover, Cp challenge and Ni altered the cecal microbiota composition, which manifested that Cp challenge decreased the relative abundance of phylum Fusobacteriota and increased Shannon index (P<0.05) and the trend of phylum Proteobacteria (0.05 Collapse

Key Words

• Clostridium perfringens
• broiler
• gut health
• necrotic enteritis
• nisin

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MESH Headings

• Animals
• Clostridium perfringens
• Chickens
• Intestines
• Clostridium Infections/prevention & control
• Clostridium Infections/veterinary
• Clostridium Infections/microbiology
• Nisin/pharmacology
• Claudin-1
• bcl-2-Associated X Protein/pharmacology
• Diet/veterinary
• RNA, Messenger/genetics
• Immunity
• Poultry Diseases/microbiology
• Dietary Supplements
• Animal Feed/analysis

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Affiliation(s)

Hua Yuan College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Guangdong Bai College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China College of Animal Science and Technology, Southwest University, Chongqing 400715, China
Yu Lin College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Xilong Yu College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Qinghui Yang College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Renkai Dou College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Hao Sun College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Zeyu Zhao College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Zhongyu Li College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Zhihui Chen College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China
Liangmei Xu College of Animal Science and Technology, Northeast Agricultural University, Harbin 150030, China

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Effects of Dietary Limosilactobacillus fermentum and Lacticaseibacillus paracasei Supplementation on the Intestinal Stem Cell Proliferation, Immunity, and Ileal Microbiota of Broiler Chickens Challenged by Coccidia and Clostridium perfringens

This study was conducted to investigate effects of dietary Limosilactobacillus fermentum and Lacticaseibacillus paracasei supplementation on the intestinal stem cell proliferation, immunity, and ileal microbiota of broiler chickens challenged by coccidia and Clostridium perfringens. A total of 336 one-day-old Ross 308 chickens were randomly assigned into four groups. Chickens in the control (CTR) group were fed basal diet, and chickens in the three challenged groups were fed basal diets supplemented with nothing (CCP group), 1.0 × 109 CFU/kg L. fermentum (LF_CCP group), and 1.0 × 109 CFU/kg L. paracasei (LP_CCP group), respectively. All challenged birds were infected with coccildia on day 9 and Clostridium perfringens during days 13-18. The serum and intestinal samples were collected on days 13 and 19. The results showed that L. fermentum significantly increased jejunal gene expression of cdxB (one of the intestinal stem cell marker genes) on day 13. Additionally, L. fermentum significantly up-regulated mRNA levels of JAK3 and TYK2 and tended to increase STAT6 mRNA expression in jejunum on day 19. In the cecal tonsil, both L. fermentum and L. paracasei decreased mRNA expression of JAK2 on day 13, and L. fermentum down-regulated JAK1-2, STAT1, and STAT5-6 gene expressions on day 19. Ileal microbiological analysis showed that coccidial infection increased the Escherichia-Shigella, Lactobacillus, and Romboutsia abundance and decreased Candidatus_Arthromitus richness on day 13, which were reversed by Lactobacillus intervention. Moreover, Lactobacilli increased ileal Lactobacillus richness on day 19. In conclusion, Lactobacilli alleviated the impairment of intestinal stem cell proliferation and immunity in coccidia- and C. perfringens-challenged birds via modulating JAK/STAT signaling and reshaping intestinal microflora.

Multi-omics analysis reveals the molecular regulatory network underlying the prevention of Lactiplantibacillus plantarum against LPS-induced salpingitis in laying hens

BACKGROUND

Salpingitis is one of the common diseases in laying hen production, which greatly decreases the economic outcome of laying hen farming. Lactiplantibacillus plantarum was effective in preventing local or systemic inflammation, however rare studies were reported on its prevention against salpingitis. This study aimed to investigate the preventive molecular regulatory network of microencapsulated Lactiplantibacillus plantarum (MLP) against salpingitis through multi-omics analysis, including microbiome, transcriptome and metabolome analyses.

RESULTS

The results revealed that supplementation of MLP in diet significantly alleviated the inflammation and atrophy of uterus caused by lipopolysaccharide (LPS) in hens (P < 0.05). The concentrations of plasma IL-2 and IL-10 in hens of MLP-LPS group were higher than those in hens of LPS-stimulation group (CN-LPS group) (P < 0.05). The expression levels of TLR2, MYD88, NF-κB, COX2, and TNF-α were significantly decreased in the hens fed diet supplemented with MLP and suffered with LPS stimulation (MLP-LPS group) compared with those in the hens of CN-LPS group (P < 0.05). Differentially expressed genes (DEGs) induced by  MLP were involved in inflammation, reproduction, and calcium ion transport. At the genus level, the MLP supplementation significantly increased  the abundance of Phascolarctobacterium, whereas decreased the abundance of Candidatus_Saccharimonas in LPS challenged hens (P < 0.05). The metabolites altered by dietary supplementation with MLP were mainly involved in galactose, uronic acid, histidine, pyruvate and primary bile acid metabolism. Dietary supplementation with MLP inversely regulates LPS-induced differential metabolites such as LysoPA (24:0/0:0) (P < 0.05).

CONCLUSIONS

In summary, dietary supplementation with microencapsulated Lactiplantibacillus plantarum prevented salpingitis by modulating the abundances of Candidatus_Saccharimonas, Phascolarctobacterium, Ruminococcus_torques_group and Eubacterium_hallii_group while downregulating the levels of plasma metabolites, p-tolyl sulfate, o-cresol and N-acetylhistamine and upregulating S-lactoylglutathione, simultaneously increasing the expressions of CPNE4, CNTN3 and ACAN genes in the uterus, and ultimately inhibiting oviducal inflammation.

The protective effects of Bacillus licheniformis against inflammatory responses and intestinal barrier damage in broilers with necrotic enteritis induced by Clostridium perfringens

BACKGROUND

Bacillus licheniformis is a gram-positive bacterium that has strong environmental adaptability and can improve the growth performance, immunity, and antioxidant function of broilers. The current study aimed to elucidate the protective capability of B. licheniformis against inflammatory responses and intestinal barrier damage in broilers with necrotic enteritis (NE) induced by Clostridium perfringens (CP).

RESULTS

The results showed that B. licheniformis enhanced the final body weight in broilers compared with that of broilers in the CP group after the stress of infection (P < 0.05). Bacillus licheniformis reversed the decreased levels of serum and jejunum mucosa immunoglobulins and anti-inflammatory cytokines, reduced the values of villus height and the ratio of villus height to crypt depth, and mitigated the increased levels of serum d-lactic acid and diamine oxidase in CP-challenged broilers (P < 0.05). Moreover, B. licheniformis modulated the expression levels of genes involved in the TLR4/NF-κB signalling pathway, the NLRP3 inflammasome activation pathway, and the sirt 1/Parkin signalling pathway in CP-challenged broilers. Compared with the CP challenge group, the B. licheniformis-treated group exhibited reduced abundance values of Shuttleworthia and Alistipes and enhanced abundance values of Parabacteroides in the caecal contents (P < 0.05).

CONCLUSION

Bacillus licheniformis improved the final body weight and alleviated the inflammatory response and intestinal barrier function damage in birds with NE induced by CP by maintaining intestinal physiological function, enhancing immunity, regulating inflammatory cytokine secretion, modulating the mitophagy response, and increasing the abundance of beneficial intestinal flora. © 2023 Society of Chemical Industry.

An Overview of the Use and Applications of Limosilactobacillus fermentum in Broiler Chickens

The implementation of government regulations on antibiotic use, along with the public's concern for drug resistance, has strengthened interest in developing alternatives not only aimed at preserving animal production but also at reducing the effects of pathogenic infections. Probiotics, in particular, are considered microorganisms that induce health benefits in the host after consumption of adequate amounts; they have been established as a potential strategy for improving growth, especially by stimulating intestinal homeostasis. Probiotics are commonly associated with lactic acid bacteria, and Limosilactobacillus fermentum is a well-studied species recognized for its favorable characteristics, including adhesion to epithelial cells, production of antimicrobial compounds, and activation of receptors that prompt the transcription of immune-associated genes. Recently, this species has been used in animal production. Different studies have shown that the application of L. fermentum strains not only improves the intestinal ecosystem but also reduces the effects caused by potentially pathogenic microorganisms. These studies have also revealed key insights into the mechanisms behind the actions exerted by this probiotic. In this manuscript, we aim to provide a concise overview of the effects of L. fermentum administration on broiler chicken health and performance.

Supplementing Genistein for Breeder Hens Alters the Growth Performance and Intestinal Health of Offspring

Recent research revealed that dietary genistein supplementation for breeder hens can improve the immune function of offspring chicks. However, it remains unknown whether this maternal effect could improve the intestinal health of offspring. This study was conducted to explore the mechanism involved in the maternal effect of genistein on the intestinal mucosa and microbial homeostasis of chicken offspring. A total of 120 Qiling breeder hens were fed a basal diet, a 20 mg/kg genistein-supplemented diet, or a 40 mg/kg genistein-supplemented diet for 4 weeks before collecting their eggs. After hatching, 180 male offspring (60 chickens from each group) were randomly selected and divided into three groups: (1) the offspring of hens fed a basal diet (CON); (2) the offspring of hens fed a low-dose genistein-supplemented diet (LGE); (3) the offspring of hens fed a high-dose genistein-supplemented diet (HGE). At 17 d, 72 male offspring (48 chickens from CON and 24 chickens from LGE) were divided into three groups: (1) the offspring of hens fed a basal diet (CON); (2) the CON group challenged with LPS (LPS); (3) the LGE group challenged with LPS (LPS + LGE). The results showed that maternal genistein supplementation increased the birth weight and serum level of total protein (TP), followed by improved intestinal villus morphology. Continuously, the maternal effect on the body weight of chicks lasted until 21 d. Additionally, it was observed that maternal genistein supplementation exhibited protective effects against LPS-induced morphological damage and intestinal mucosal barrier dysfunction by upregulating the expression of tight junction proteins, specifically ZO-1, Claudin1, E-cadherin, and Occludin, at 21 d. Using 16S rRNA gene sequencing, we demonstrated that maternal supplementation of genistein has the potential to facilitate the maturation of newly hatched chicken offspring by enhancing the abundance of Escherichia coli. Additionally, maternal genistein supplementation can effectively reduce the abundance of Gammaproteobacteria, thus mitigating the risk of bacterial diversity impairment of LPS. In light of these findings, maternal genistein supplementation holds promise as a potential strategy for ameliorating intestinal mucosal damage and modulating the microbiome in chicken offspring.

Dietary Probiotics Modulate Gut Barrier and Immune-Related Gene Expression and Histomorphology in Broiler Chickens under Non- and Pathogen-Challenged Conditions: A Meta-Analysis

Data published in the literature about the favorable effects of dietary probiotics on gut health in broiler chickens are inconsistent. To obtain a more comprehensive understanding, we conducted a meta-analysis to assess the effects of probiotics on the gut barrier and immune-related gene expression, histomorphology, and growth in chickens that were either challenged or non-challenged with pathogens. From the 54 articles published between 2012 and 2022, subsets of data, separately for non-challenged and challenged conditions, for response variables were created. The mean dietary probiotic concentrations ranged from 4.7 to 6.2 and 4.7 to 7.2 log₁₀ colony-forming unit/kg under non-challenged and challenged conditions, respectively. Probiotics increased the expression of genes for mucins and tight junction proteins in the jejunum and ileum at weeks 3 and 6. The stimulatory effect of probiotics on tight junction protein expression was partly stronger in challenged than in non-challenged birds. Meta-regressions also showed an anti-inflammatory effect of probiotics under challenged conditions by modulating the expression of cytokines. Probiotics improved villus height at certain ages in the small intestine while not influencing growth performance. Dietary metabolizable energy, crude protein, and days post-infection modified the effects of probiotics on the observed variables. Overall, meta-regressions support the beneficial effects of probiotics on gut integrity and structure in chickens.

Effects of Vitamin A on Immune Responses and Vitamin A Metabolism in Broiler Chickens Challenged with Necrotic Enteritis

Necrotic enteritis (NE) is an important enteric inflammatory disease of poultry, and the effects of vitamin A (VitA) on NE birds are largely unknown. The present study was conducted to investigate the effects of VitA on the immune responses and VitA metabolism of NE broilers as well as the underlying mechanisms. Using a 2 × 2 factorial arrangement, 336 1-day-old Ross 308 broiler chicks were randomly assigned to 4 groups with 7 replicates. Broilers in the control (Ctrl) group were fed a basal diet without extra VitA supplementation. Broilers in the VitA group were fed a basal diet supplemented with 12,000 IU/kg of VitA. Birds in NE and VitA + NE groups were fed corresponding diets and, in addition, co-infected with Eimeria spp. and Clostridium perfringens on days 14 to 20. Samples of the blood, jejunum, spleen and liver were obtained on day 28 for analysis, and meanwhile, lesion scores were also recorded. The results showed that NE challenge increased lesion score in the jejunum and decreased serum glucose, total glyceride, calcium, phosphorus and uric acid levels (p < 0.05). VitA supplementation reduced the levels of serum phosphorus, uric acid and alkaline phosphatase in NE-challenged birds and increased serum low-density lipoprotein content and the activity of aspartate aminotransferase and creatine kinase (p < 0.05). Compared with the Ctrl group, the VitA and NE groups had higher mRNA expression of interferon-γ in the jejunum (p < 0.05). NE challenge up-regulated mRNA expression of interleukin (IL)-13, transforming growth factor-β4, aldehyde dehydrogenase (RALDH)-2 and RALDH-3 in the jejunum, while VitA supplementation increased jejunal IL-13 mRNA expression and hepatic VitA content, but down-regulated splenic IL-13 mRNA expression (p < 0.05). The VitA + NE group had higher serum prostaglandin E₂ levels and the Ctrl group had higher splenic RALDH-3 mRNA expression than that of the other three groups (p < 0.05). NE challenge up-regulated jejunal retinoic acid receptor (RAR)-β and retinoid X receptor (RXR)-α as well as splenic RAR-α and RAR-β mRNA expression (p < 0.05). VitA supplementation up-regulated jejunal RAR-β expression but down-regulated mRNA expression of RXR-α, RXR-γ, signal transducers and activators of transcription (STAT) 5 and STAT6 in the spleen (p < 0.05). Moreover, compared with the Ctrl group, the VitA and NE groups had down-regulated mRNA expression of jejunal and splenic Janus kinase (JAK) 1 (p < 0.05). In conclusion, NE challenge induced jejunal injury and expression of Th2 and Treg cell-related cytokines and enhanced RALDH and RAR/RXR mRNA expression, mainly in the jejunum of broilers. VitA supplementation did not alleviate jejunal injury or Th2 cell-related cytokine expression; however, it improved hepatic VitA deposition and inhibited the expression of RALDH-3, RXR and the JAK/STAT signaling pathway in the spleen of broilers. In short, the present study suggested the modulatory effects of vitamin A on the immune responses and vitamin A metabolism in broiler chickens challenged with necrotic enteritis.

Recent Trends on Mitigative Effect of Probiotics on Oxidative-Stress-Induced Gut Dysfunction in Broilers under Necrotic Enteritis Challenge: A Review

Gut health includes normal intestinal physiology, complete intestinal epithelial barrier, efficient immune response, sustained inflammatory balance, healthy microbiota, high nutrient absorption efficiency, nutrient metabolism, and energy balance. One of the diseases that causes severe economic losses to farmers is necrotic enteritis, which occurs primarily in the gut and is associated with high mortality rate. Necrotic enteritis (NE) primarily damages the intestinal mucosa, thereby inducing intestinal inflammation and high immune response which diverts nutrients and energy needed for growth to response mediated effects. In the era of antibiotic ban, dietary interventions like microbial therapy (probiotics) to reduce inflammation, paracellular permeability, and promote gut homeostasis may be the best way to reduce broiler production losses. The current review highlights the severity effects of NE; intestinal inflammation, gut lesions, alteration of gut microbiota balance, cell apoptosis, reduced growth performance, and death. These negative effects are consequences of; disrupted intestinal barrier function and villi development, altered expression of tight junction proteins and protein structure, increased translocation of endotoxins and excessive stimulation of proinflammatory cytokines. We further explored the mechanisms by which probiotics mitigate NE challenge and restore the gut integrity of birds under disease stress; synthesis of metabolites and bacteriocins, competitive exclusion of pathogens, upregulation of tight junction proteins and adhesion molecules, increased secretion of intestinal secretory immunoglobulins and enzymes, reduction in pro-inflammatory cytokines and immune response and the increased production of anti-inflammatory cytokines and immune boost via the modulation of the TLR/NF-ĸ pathway. Furthermore, increased beneficial microbes in the gut microbiome improve nutrient utilization, host immunity, and energy metabolism. Probiotics along with biosecurity measures could mitigate the adverse effects of NE in broiler production.

Alleviative effects of a novel strain Bacillus coagulans XY2 on copper-induced toxicity in zebrafish larvae

Copper (Cu) is a kind of micronutrient element that is essential for human metabolism. However, it is also considered as an environmental pollutant which is toxic to organisms at a high concentration level. Probiotics, regarded as beneficial microorganisms for promoting human health, have functions of antioxidant capacity, immune-enhancing properties, intestinal barrier protection and regulation. Several studies have reported that probiotics show positive effects on alleviating and intervening heavy metals toxicity. However, evidence for relieving copper-induced toxicity by probiotics is still limited. In this study, we firstly conducted a zebrafish larvae model to screen out microorganisms which are helpful for CuSO₄ toxicity resistance and one novel strain named as Bacillus coagulans XY2 was discovered with the best protective activity. B. coagulans XY2 significantly reduced the mortality of zebrafish larvae exposed to 10 µmol/L CuSO₄ for 96 hr, as well as alleviated the neutrophils infiltration in the larvae lateral line under a 2 hr exposure. B. coagulans XY2 exhibited a high in vitro antioxidant activity and against CuSO₄-induced oxidative stress in zebrafish larvae by up-regulating sod1, gstp1 and cat gene transcriptional levels and relevant enzymatic activities. CuSO₄ stimulated the inflammation process resulting in obvious increases of gene il-1β and il-10 transcription, which were suppressed by B. coagulans XY2 intervention. Overall, our results underline the bio-function of B. coagulans XY2 on protecting zebrafish larvae from copper toxicity, suggesting the potential application values of probiotics in copper toxicity alleviation on human and the environment.

Screening and Characterization of Pediococcus acidilactici LC-9-1 toward Selection as a Potential Probiotic for Poultry with Antibacterial and Antioxidative Properties

Growing interest has been focused on lactic acid bacteria as alternatives to antimicrobial growth promoters, which are characterized by the production of various functional metabolites, such as antimicrobial and antioxidants compounds. The present study was undertaken to evaluate a potential probiotic from the antioxidant perspective. LC-9-1, screened from the intestines of healthy animals, was revealed to be Pediococcus acidilactici on the basis of its morphological, biochemical, and molecular characteristics. The strain has excellent properties, including acid-production efficiency, antibacterial performance and antioxidant activity. The safety of the strain was also evaluated. Furthermore, the experiments in broiler chickens suggested that dietary LC-9-1 supplementation improved the growth performance and decreased the abdominal fat, and enhanced the antioxidant capability and intestinal innate immunity of broilers. Analysis of intestinal microbiota showed that a higher community diversity (Shannon index) was achieved. In addition to the significantly increased relative abundances of Pediococcus spp., beneficial genera such as Rothia spp. and Ruminococcus spp. were abundant, while opportunistic pathogens such as Escherichia-Shigella spp. were significantly reduced in LC-9-1-supplemented broilers. Collectively, such in-depth characterization and the available data will guide future efforts to develop next-generation probiotics, and LC-9-1 could be considered a potential strain for further utilization in direct-fed microbial or starter culture for fermentation.

The effect of Bacillus subtilis and its delivery route on hatch and growth performance, blood biochemistry, immune status, gut morphology, and microbiota of broiler chickens

This study evaluated the effect of probiotics (Bacillus subtilis fermentation extract) and its delivery route (in-feed or in ovo) on hatch and growth performance, blood biochemistry, immune status, gut morphology, and microbiota of broiler chickens. Hatching eggs were incubated for 21 d. On d 12, viable eggs were randomly allotted to 4 groups: the noninjected, in ovo saline (S), in ovo Bacillus subtilis 1 (P1), and in ovo Bacillus subtilis 2 (P2). On d 18, S, P1, and P2 groups received 0.2 mL saline diluent, 10 × 10⁶, and 20 × 10⁶ CFU of the bacterium via the amnion, respectively. At hatch, chicks were re-allotted to 5 new treatment groups: P1, P2, 0.005% in-feed Bacillus subtilis extract (P3), 0.05% in-feed bacitracin methylene disalicylate (BMD,), and corn-wheat-soybean diet negative control (NC) in 9 replicate pens (22 birds/pen) and raised for 35 d. Hatch parameters were assessed on d 0, and growth performance indices measured weekly. On d 25, 1 bird/cage was euthanized, and samples collected for further analysis. Data were analyzed by generalized linear model. Treatments S and P2 recorded higher (P = 0.01) chick BW/ Egg Weight values compared to the non-injected eggs. P3 and P2 reduced (P = 0.02) FI at week 5 compared to the NC treatment. However, no change in average body weight gain (ABG) and feed conversion ratio (FCR) were observed during the same period. At d 35, while BMD treatment showed a tendency (P = 0.09) to increase FI compared to the NC treatment, ABG and FCR were similar for all treatments. Blood sodium and chloride levels were increased (P < 0.05) by the BMD treatment compared to the NC treatment. Compared to other treatments, BMD and P3 treatments increased (P < 0.001) jejunal and ileal villus height to crypt depth ratios, respectively. However, P1 and P2 increased (P < 0.001) villus height to crypt depth ratio in the duodenum compared to NC treatment. Treatments did not affect gut microbial diversity; however, BMD treatment increased (P < 0.05) the proportion of bacteria in the genus Enterococcus in the ileum and reduced (P < 0.05) the proportion of bacteria in the genus Streptococcus in the ceca. All probiotics treatments (irrespective of route and dose) reduced (P < 0.001) the levels of serum IgG compared to the NC treatment. However, P1 and P2 had the lowest numerical decrease in serum IgG concentrations, suggesting that Bacillus subtilis (especially in ovo delivered) might provide broiler chickens with better immunological protection by neutralizing pathogenic organisms that could result in the production of natural antibodies.

Dietary Weizmannia coagulans Strain SANK70258 Ameliorates Coccidial Symptoms and Improves Intestinal Barrier Functions of Broilers by Modulating the Intestinal Immunity and the Gut Microbiota

To determine the mechanisms by which Weizmannia coagulans SANK70258 (WC) supplementation improved growth performance and coccidial symptoms, we assessed the gene expressions and the microbiota compositions in the small intestinal tissues and digestas of coccidium-infected broilers previously given WC or lasalocid-A sodium (AM). WC supplementation significantly upregulated the gene expressions related to intestinal immunity and barrier functions, such as IL17A, IL17F, IL10, cathelicidin-2 and pIgR. Body weights, and Claudin-1 and IL10 expressions were positively correlated (r = 0.41, p < 0.05 and r = 0.37, p = 0.06, respectively), whereas lesion scores of the small intestine and IL17A expression were negatively correlated (r = −0.33, p = 0.09). The microbiota analysis detected that genus Alistipes was more abundant in WC-supplemented broilers than in control, and positively correlated with body weights and Claudin-1 expression (r = 0.61, p < 0.05 and r = 0.51, p < 0.05, respectively). Intriguingly, genus Enterococcus was most abundant in WC-supplemented broilers and positively correlated with IL17A expression (r = 0.49, p < 0.05). Interestingly, Escherichia-Shigella was significantly more abundant in the small intestinal digestas of AM-administered broilers than in those of control. To summarize, WC supplementation modulated and immunostimulated the microbiotas of broilers, specifically genera Alistipes and Enterococcus, which led to the improvement of weight gain and coccidial symptoms, without disrupting the intestinal microbiota compositions, as AM did.

Succession, Replacement, and Modification of Chicken Litter Microbiota

Chickens are in constant interaction with their environment, e.g., bedding and litter, and their microbiota. However, how litter microbiota develops over time and whether bedding and litter microbiota may affect the cecal microbiota is not clear. We addressed these questions using sequencing of V3/V4 variable region of 16S rRNA genes of cecal, bedding, and litter samples from broiler breeder chicken flocks for 4 months of production. Cecal, bedding, and litter samples were populated by microbiota of distinct composition. The microbiota in the bedding material did not expand in the litter. Similarly, major species from litter microbiota did not expand in the cecum. Only cecal microbiota was found in the litter forming approximately 20% of total litter microbiota. A time-dependent development of litter microbiota was observed. Escherichia coli, Staphylococcus saprophyticus, and Weissella jogaejeotgali were characteristic of fresh litter during the first month of production. Corynebacterium casei, Lactobacillus gasseri, and Lactobacillus salivarius dominated in a 2-month-old litter, Brevibacterium, Brachybacterium, and Sphingobacterium were characteristic for 3-month-old litter, and Salinococcus, Dietzia, Yaniella, and Staphylococcus lentus were common in a 4-month-old litter. Although the development was likely determined by physicochemical conditions in the litter, it might be interesting to test some of these species for active modification of litter to improve the chicken environment and welfare. IMPORTANCE Despite intimate contact, the composition of bedding, litter, and cecal microbiota differs considerably. Species characteristic for litter microbiota at different time points of chicken production were identified thus opening the possibility for active manipulation of litter microbiota.

Dietary Lactobacillus fermentum and Lactobacillus paracasei improve the intestinal health of broilers challenged with coccidia and Clostridium perfringens

Necrotic enteritis (NE) is a great threat to the intestinal health of broilers, resulting in decreased growth performance and significant economic losses. Lactobacillus fermentum (LF) and Lactobacillus paracasei (LP) exert beneficial effects on intestinal health. The aim of the present study was to investigate the effects of dietary LF and LP on the intestinal health and growth performance of broilers challenged with coccidia and Clostridium perfringens (CCP). The animal trial was carried out using 336 broilers (Ross 308) for 35 days with a completely randomized design. The broilers were divided into 4 groups based on treatment as follows: the control (CTR) group was fed the basal diet and without CCP challenge and the CCP group was fed the basal diet and with CCP challenge. The broilers in the CCP+LF and CCP+LP groups were challenged by CCP, and meanwhile, LF (1 × 10⁹ CFU/g) and LP (1 × 10⁹ CFU/g) were supplemented into the basal diets, respectively. The results showed that the growth performance and the intestinal morphology were negatively affected by the CCP challenge. In addition, the number of coccidia in the intestinal digesta and the relative abundance of Escherichia coli in the cecal digesta were increased. Besides, the mRNA level of IgA in the jejunum was downregulated, and the transcript level of IL-8 was upregulated by the CCP challenge. Dietary LF and LP failed to improve the growth performance of broilers with the CCP challenge. However, they were beneficial for intestinal barrier function. In addition, dietary LF was able to alleviate the downregulation of TGF-β mRNA level in the spleen with CCP challenge and decreased the lesion scores compared with the CCP group. Furthermore, dietary LP alleviated the upregulation of the IL-8 mRNA level in the jejunum with CCP challenge and reduced the number of coccidia in the ileal digesta. In conclusion, dietary LF and LP failed to mitigate the negative effects of CCP infection on growth performance; however, they were able to improve the intestinal health of broilers challenged with CCP by strengthening the intestinal barrier and alleviating inflammation.

Effects of Dietary Supplementation with Vitamin A on Antioxidant and Intestinal Barrier Function of Broilers Co-Infected with Coccidia and Clostridium perfringens

Necrotic enteritis (NE) impairs poultry production and causes great economic loss. The nutritional regulation of diets has the potential to alleviate NE. The present study was conducted to investigate the effects of dietary supplementation with vitamin A (VA) on the antioxidant and intestinal barrier function of broilers co-infected with coccidia and C. perfringens (CCP). In a 2 × 2 factorial arrangement, 336 one-day-old Ross 308 broilers were divided into four treatments with two levels of VA (0 or 12,000 IU/kg) and challenged with or without CCP. The animal trial lasted for 42 days. The results showed that dietary supplemental VA improved body weight gain (BWG) and the feed intake (FI), and the FI was negatively affected by CCP. Additionally, the levels of catalase (CAT) in the serum, total superoxide dismutase (T-SOD), and CAT in the jejunum and glutathione peroxidase (GSH-Px) in the liver decreased with the CCP challenge (p < 0.05). The mRNA levels of SOD, CAT, GSH-Px1, and GSH-Px3 in the liver and jejunum were upregulated by the CCP challenge (p < 0.05). In addition, the level of serum diamine oxidase (DAO), and the mRNA level of ZO-1 were also upregulated with the CCP challenge. Dietary supplementation with VA contributed to the intestinal villi height and the mRNA level of Mucin-2 in the jejunum (p < 0.05). Additionally, dietary VA had the ability to alleviate the upregulation of SOD in the liver and SOD, CAT, GSH-Px1, GSH-Px3, ZO-1, and claudin-1 in the jejunum with the CCP challenge (p < 0.05). However, the mRNA level of GSH-Px3 and the levels of SOD in the liver and jejunum were downregulated with the VA supplementation in the diet. In conclusion, dietary VA improved the growth performance and the intestinal barrier function; nonetheless, it failed to alleviate the negative effects of CCP on the antioxidant function in broilers.

Chicken Gut Microbiota Responses to Dietary Bacillus subtilis Probiotic in the Presence and Absence of Eimeria Infection

Coccidiosis is a well-known poultry disease that causes the severe destruction of the intestinal tract, resulting in reduced growth performance and immunity, disrupted gut homeostasis and perturbed gut microbiota. Supplementation of probiotics were explored to play a key role in improving growth performance, enhancing innate and adaptive immunity, maintaining gut homeostasis and modulating gut microbiota during enteric infection. This study was therefore designed to investigate the chicken gut whole microbiota responses to Bacillus subtilis (B. subtilis) probiotic feeding in the presence as well as absence of Eimeria infection. For that purpose, 84 newly hatched chicks were assigned into four groups, including (1) non-treated non-challenged control group (CG - ET), (2) non-treated challenged control group (CG + ET), (3) B. subtilis-fed non-challenged group (BS - ET) and (4) B. subtilis-fed challenged group (BS + ET). CG + ET and BS + ET groups were challenged with Eimeria tenella (E. tenella) on 21 day of housing. Our results for Alpha diversity revealed that chickens in both infected groups (CG + ET and BS + ET) had lowest indexes of Ace, Chao 1 and Shannon, while highest indexes of Simpson were found in comparison to non-challenged groups (CG - ET and BS - ET). Firmicutes was the most affected phylum in all experimental groups following Proteobacteria and Bacteroidota, which showed increased abundance in both non-challenged groups, whereas Proteobacteria and Bacteroidota affected both challenged groups. The linear discriminant analysis effect size method (lEfSe) analysis revealed that compared to the CG + ET group, supplementation of probiotic in the presence of Eimeria infection increased the abundance of some commensal genera, included Clostridium sensu stricto 1, Corynebacterium, Enterococcus, Romboutsia, Subdoligranulum, Bacillus, Turicibacter and Weissella, with roles in butyrate production, anti-inflammation, metabolic reactions and the modulation of protective pathways against pathogens. Collectively, these findings evidenced that supplementation of B. subtilis probiotic was positively influenced with commensal genera, thereby alleviating the Eimeria-induced intestinal disruption.

Dietary Supplementation With Lactobacillus plantarum Ameliorates Compromise of Growth Performance by Modulating Short-Chain Fatty Acids and Intestinal Dysbiosis in Broilers Under Clostridium perfringens Challenge

Clostridium perfringens is an important zoonotic pathogen associated with food contamination and poisoning, gas gangrene, necrotizing enterocolitis or necrotic enteritis in humans and animals. Dysbacteriosis is supposedly associated with the development of C. perfringens infection induced necrotic enteritis, but the detailed relationship between intestinal health, microbiome, and C. perfringens infection-induced necrotic enteritis remains poorly understood. This research investigated the effect of probiotics on the growth performance and intestinal health of broilers, and the involved roles of intestinal microbiota and microbial metabolic functions under C. perfringens infection. Results showed that subclinical necrotic enteritis was successfully induced as evidenced by the significant lower body weight (BW), suppressed feed conversion ratio (FCR), decreased ileal villus height and mucosal barrier function, and increased ileal histopathological score and bursal weight index. Lactobacillus plantarum or Paenibacillus polymyxa significantly attenuated C. perfringens-induced compromise of growth performance (BW, FCR) and ileal mucosa damage as illustrated by the increased ileal villus height and villus/crypt ratio, the decreased ileal histopathological score and the enhanced ileal mucosal barrier function. L. plantarum also significantly alleviated C. perfringens-induced enlarged bursa of fabricius and the decreased levels of ileal total SCFAs, acetate, lactate, and butyrate. Furthermore, dietary L. plantarum improved C. perfringens infection-induced intestinal dysbiosis as evidenced by significantly enriched short-chain fatty acids-producing bacteria (Lachnospiraceae, Ruminococcaceae, Oscillospira, Faecalibacterium, Blautia), reduced drug-resistant bacteria (Bacteroides, Alistipes) and enteric pathogens (Escherichia coli, Bacteroides fragilis) and bacterial metabolic dysfunctions as illustrated by significantly increased bacterial fatty acid biosynthesis, decreased bacterial lipopolysaccharide biosynthesis, and antibiotic biosynthesis (streptomycin and vancomycin). Additionally, the BW and intestinal SCFAs were the principal factors affecting the bacterial communities and microbial metabolic functions. The above findings indicate that dietary with L. plantarum attenuates C. perfringens-induced compromise of growth performance and intestinal dysbiosis by increasing SCFAs and improving intestinal health in broilers.

Coccidia-Microbiota Interactions and Their Effects on the Host

As a common parasitic disease in animals, coccidiosis substantially affects the health of the host, even in the absence of clinical symptoms and intestinal tract colonization. Gut microbiota is an important part of organisms and is closely related to the parasite and host. Parasitic infections often have adverse effects on the host, and their pathogenic effects are related to the parasite species, parasitic site and host-parasite interactions. Coccidia-microbiota-host interactions represent a complex network in which changes in one link may affect the other two factors. Furthermore, coccidia-microbiota interactions are not well understood and require further research. Here, we discuss the mechanisms by which coccidia interact directly or indirectly with the gut microbiota and the effects on the host. Understanding the mechanisms underlying coccidia-microbiota-host interactions is important to identify new probiotic strategies for the prevention and control of coccidiosis.