Transplantion of predominant Lactobacilli from native hens to commercial hens could indirectly regulate their ISC activity by improving intestinal microbiota

Significant Differences in Intestinal Bacterial Communities of Sympatric Bean Goose, Hooded Crane, and Domestic Goose

The host's physiological well-being is intricately associated with the gut microbiota. However, previous studies regarding the intestinal microbiota have focused on domesticated or captive birds. This study used high-throughput sequencing technology to identify the gut bacterial communities of sympatric bean geese, hooded cranes, and domestic geese. The results indicated that the gut bacterial diversity in domestic geese and hooded cranes showed considerably higher diversity than bean geese. The gut bacterial community compositions varied significantly among the three hosts (p < 0.05). Compared to the hooded crane, the bean goose and domestic goose were more similar in their genotype and evolutionary history, with less difference in the bacterial community composition and assembly processes between the two species. Thus, the results might support the crucial role of host genotypes on their gut microbiota. The gut bacteria of wild hooded cranes and bean geese had a greater capacity for energy metabolism compared to domestic geese, suggesting that wild birds may rely more on their gut microbiota to survive in cold conditions. Moreover, the intestines of the three hosts were identified as harboring potential pathogens. The relative abundance of pathogens was higher in the hooded crane compared to the other two species. The hooded crane gut bacterial community assemblage revealed the least deterministic process with the lowest filtering/selection on the gut microbiota, which might have been a reason for the highest number of pathogens result. Compared to the hooded crane, the sympatric bean goose showed the least diversity and relative abundance of pathogens. The intestinal bacterial co-occurrence network showed the highest stability in the bean goose, potentially enhancing host resistance to adverse environments and reducing the susceptibility to pathogen invasion. In this study, the pathogens were also discovered to overlap among the three hosts, reminding us to monitor the potential for pathogen transmission between poultry and wild birds. Overall, the current findings have the potential to enhance the understanding of gut bacterial and pathogenic community structures in poultry and wild birds.

Protective effects of Lactobacillus on heat stress-induced intestinal injury in finisher broilers by regulating gut microbiota and stimulating epithelial development

Heat stress (HS) is a critical challenge in broilers due to the high metabolic rate and lack of sweat glands. Results from this study show that implementing a cyclic chronic HS (34 °C for 7 h/d) to finisher broilers decreased the diversity of cecal microbiota and impaired intestinal barrier, resulting in gut leak and decreased body weight (both P < 0.05). These alterations might be related to inflammatory outbursts and the retarded proliferation of intestinal epithelial cells (IECs) according to the transcriptome analysis. Considering the potential beneficial properties of Lactobacillus on intestinal development and function, the protective effects of Lactobacillus rhamnosus (L. rhamnosus) on the intestine were investigated under HS conditions in this study. Orally supplemented L. rhamnosus improved the composition of cecal microbiota and upregulated the transcription of tight junction proteins in both duodenum and jejunum, with a consequent suppression in intestinal gene expressions of pro-inflammatory cytokines and facilitation in digestive capability. Meanwhile, the jejunal villus height of the birds that received L. rhamnosus was significantly higher compared with those treated with the broth (P < 0.05). The expression abundances of genes related to IECs proliferation and differentiation were increased by L. rhamnosus, along with upregulated mRNA levels of Wnt3a and β-catenin in jejunum. In addition, L. rhamnosus attenuated enterocyte apoptosis as indicated by decreased caspase-3 and caspase-9 gene expressions. The results indicated that oral administration with L. rhamnosus mitigated HS-induced dysfunction by promoting intestinal development and epithelial maturation in broilers and that the effects of L. rhamnosus might be dependent of Wnt/β-catenin signaling.

Dietary Chinese herbal mixture supplementation improves production performance by regulating reproductive hormones, antioxidant capacity, immunity, and intestinal health of broiler breeders

Chinese herbs have been used as feed additives and are commonly utilized in domestic intensive livestock farming. However, their impact on the production performance and intestinal health of broiler breeders has yet to be thoroughly explored. This study aimed to evaluate the effects of a Chinese herbal mixture (CHM) on the production performance of broiler breeders in terms of reproductive hormones, antioxidant capacity, immunity, and intestinal health of broiler breeders. A total of 336 thirty-wk-old hens were randomly allotted to 4 groups with 6 replicates of fourteen hens each, which fed a basal diet supplemented with 0 (CON), 500 (CHM500), 1,000 (CHM1000), and 1,500 (CHM1500) mg/kg CHM for 56 days, respectively. Our results showed that dietary supplementation with CHM1000 increased the laying rate and number of SYF and decreased the feed conversion ratio (P < 0.05). All CHM groups increased oviduct and ovarian indexes, serum E2 and T-AOC levels, and decreased serum TG and MDA levels compared with CON (P < 0.05). In comparison to the CON group, the CHM1000 and CHM1500 groups increased serum ALB, IgM, and IL-10 levels, whereas the CHM1000 group also increased serum TP and SOD levels, and the CHM1500 group increased serum P and decreased serum TNF-α (P < 0.05). The addition of CHM increased FSHR expressions in the ovary, Claudin-1 expressions in the jejunum, and SOD1 expressions in the liver and ovary, but decreased the mRNA expressions of INH in the ovary as well as IL-2 and IL-6 expressions in the jejunum (P < 0.05). Moreover, CHM500 and CHM1000 groups increased CAT, GPx, and HO-1 expression in the ovary, and SOD1 and GPx expression in the jejunum, while decreasing IL-17A expression in the jejunum (P < 0.05). In addition, CHM1000 and CHM1500 groups increased villus height, VCR, and the mRNA expressions of Nrf2, HO-1, Occludin, and MUC2 in the jejunum, and IL-10 expression in the ovary, while decreasing IL-2 and IL-17A expression in the ovary, in addition to increasing GPx, Nrf2, HO-1, NQO1, and IL-10 expression in the liver (P < 0.05). Supplementation with CHM1000 increased ESR-α, ESR-β, GnRH, Nrf2, and NQO1 expression in the ovary, but decreased IFN-γ expression in the ovary as well as crypt depth in the jejunum (P < 0.05). Supplementing CHM1500 increased NQO1 and ZO-1 expression in the jejunum and decreased IL-2 in the liver (P < 0.05). The high-throughput sequencing results showed that dietary CHM1000 supplementation altered the composition of the intestinal microbiota, as evidenced by the regulation of the genera Lactobacillus, Faecalibacterium, and Phascolarctobacterium. PICRUSt analysis revealed that metabolic pathways of bacterial chemotaxis, butanoate metabolism, and synthesis and degradation of ketone bodies were enriched in the CHM1000 group. Spearman's correlation analysis indicated that the differentiated genera were significantly associated with the production performance, serum hormone, and gut barrier-related genes. Taken together, supplementation of CHM, especially at 1,000 mg/kg, could improve production performance by regulating reproductive hormones, antioxidant capacity, immunity, and intestinal health of broiler breeders, and maybe provide insights into its application as a potential feed additive to promote the performance of broiler breeders.

Host specific adaptations of Ligilactobacillus aviarius to poultry

The genus Ligilactobacillus encompasses species adapted to vertebrate hosts and fermented food. Their genomes encode adaptations to the host lifestyle. Reports of gut microbiota from chicken and turkey gastrointestinal tract have shown a high persistence of Ligilactobacillus aviarius along the digestive system compared to other species found in the same host. However, its adaptations to poultry as a host has not yet been described. In this work, the pan-genome of Ligilactobacillus aviarius was explored to describe the functional adaptability to the gastrointestinal environment. The core genome is composed of 1179 gene clusters that are present at least in one copy that codifies to structural, ribosomal and biogenesis proteins. The rest of the identified regions were classified into three different functional clusters of orthologous groups (clusters) that codify carbohydrate metabolism, envelope biogenesis, viral defence mechanisms, and mobilome inclusions. The pan-genome of Ligilactobacillus aviarius is a closed pan-genome, frequently found in poultry and highly prevalent across chicken faecal samples. The genome of L. aviarius codifies different clusters of glycoside hydrolases and glycosyltransferases that mediate interactions with the host cells. Accessory features, such as antiviral mechanisms and prophage inclusions, variate amongst strains from different GIT sections. This information provides hints about the interaction of this species with viral particles and other bacterial species. This work highlights functional adaptability traits present in L. aviarius that make it a dominant key member of the poultry gut microbiota and enlightens the convergent ecological relation of this species to the poultry gut environment.

Canaries' Microbiota: The Gut Bacterial Communities along One Female Reproductive Cycle

Investigations of bacterial communities are on the rise both in human and veterinary medicine. Their role in health maintenance and pathogenic mechanisms is in the limelight of infectious, metabolic, and cancer research. Among the most considered, gut bacterial communities take the cake. Their part in animals was assessed mainly to improve animal production, public health, and pet management. In this regard, canaries deserve attention, being a popular pet and source of economic income for bird-keepers, for whom breeding represents a pivotal point. Thus, the present work aimed to follow gut bacterial communities' evolution along on whole reproductive cycle of 12 healthy female canaries. Feces were collected during parental care, molting, and resting phase, and submitted for 16S rRNA sequencing. Data were analyzed and a substantial presence of Lactobacillus aviarius along all the phases, and a relevant shift of microbiota during molting and rest due to an abrupt decrease of the Vermiphilaceae family were detected. Although the meaning of such change is not clear, future research may highlight unforeseen scenarios. Moreover, Lactobacillus aviarius may be deemed for normal bacteria flora restoration in debilitated birds, perhaps improving their health and productivity.

Dietary supplementation with probiotics increases growth performance, improves the intestinal mucosal barrier and activates the Wnt/β-catenin pathway activity in chicks

BACKGROUND

Probiotics comprise effective feed additives that can replace antibiotics in animal livestock production. However, mono-strain probiotics appear less effective because of their instability. Therefore, the present study aimed to investigate dietary supplementation with compound probiotics (CPP) on growth performance, diarrhea rate and intestinal mucosal barrier, as well as the possible molecular mechanism, in chicks. In total, 360 1-day-old chicks of the Hy-Line Brown Chicks were randomly divided into the control group (CON, basal diet), chlortetracycline group (500 mg kg^-1 CTC) and compound probiotics group (1000 mg kg^-1 CPP, consisting of Bacillus subtilis, Bacillus licheniformis, Enterococcus faecium and yeast). The experiment period was 56 days.

RESULTS

The results showed that, in comparison with the CON group, CPP significantly increased the average daily feed intake and average daily gain of chicks and reduced diarrhea (P < 0.05). The probiotic group exhibited increased immune organ (i.e. spleen and thymus) mass and increased levels of serum immunoglobulin (Ig)A, IgM and IgG (P < 0.05) compared to the CTC group. In addition, the jejunal mass and morphology were improved in the probiotic group (P < 0.05). Moreover, CPP reinforced jejunal barrier function, as indicated by increased transepithelial electrical resistance, protein expression of occludin and claudin-1, and diamine oxidase levels in the jejunum (P < 0.05). Likewise, enhanced fluorescence signals of proliferating cell nuclear antigen-labeled mitotic cells and villin-labeled absorptive cells in the jejunum (P < 0.05) suggested that CPP promoted intestinal stem cells activity. Mechanistically, the Wnt/β-catenin signaling pathway, including β-catenin, TCF4, c-Myc, cyclin D1 and Lgr5, was amplified in the jejunum by CPP addition (P < 0.05).

CONCLUSION

The present study demonstrated that dietary supplementation with CPP reinforced the jejunal epithelial integrity by activating Wnt/β-catenin signaling and enhanced immune function in chicks. © 2023 Society of Chemical Industry.

Lactobacillus Plantarum injection at the embryonic stage alters the early growth performance and lipid metabolism of broilers by specific genera of bacteria

The main objective of this study was to explore the effects of broiler embryonic injection of Lactobacillus Plantarum on the growth performance, lipid metabolism of serum and liver, microbial diversity, and short-chain fatty acids of broiler intestines after hatching. On d 14 of incubation, 720 eggs of Arbor Acres were randomly divided into 4 experimental groups: no treatment control (C), Treatments injected with stroke-physiological saline solution (S), Supernatant of MRS medium culture of lactobacillus (Q) and Lactobacillus Plantarum spp. (J). The Hatch rate for each replicate was counted at 1 d of age. After hatching, each group were divided into six replicates of 10 broilers, and chicken from groups C, Q and J were reared until 14 d of age. The production performance of the three groups of chicks from 1 to 14 days was recorded and statistically analyzed separately. Serum and liver tissue were collected at 7 and 14 days of age for the detection of lipid metabolism index. 16S rDNA sequencing and Short-Chain Fatty Acids measurement of cecum contents were performed at 14 days of age. Overall, Lactobacillus injection significantly reduced feed conversion ratio (FCR) at 1-7 and 1-14 days of age, compared to the other 2 groups (P < 0.05). 16S rRNA sequencing results showed that the Roseburia and coprobacillus had a significantly positive correlation with body weight (P < 0.05). The Roseburia and lachnospira were significantly correlated with FCR (P < 0.05), and the absolute abundance of g_Anaerostipes as a biomarker in the J group was higher than in the C group (P < 0.05). The Q and J group increased the content of acetic, propionic, butyric, and total acid in the cecum contents (P < 0.05). In the jejunum, the J group increased the content of acetic, propionic, butyric, and total acids compared to the C and Q groups (P < 0.05). The J group increased the blood of total cholesterol (TC) content at 1 day of age and the triglyceride (TG) content of 7- and 14-day-old broilers (P < 0.05). and the J group raised the TG, TC, and high-density lipoprotein (HDL) level in the liver of 14-day-old broilers (P < 0.05). The J group reduced the liver's low-density lipoprotein (LDL) at 14 days of age (P < 0.05). In conclusion, the lactobacillus Plantarum injection at the embryonic stage alters lipid metabolism by short-chain fatty acids especially butyric produced by the specific bacteria of Roseburia and Anaerostipes.

Lactobacillus salivarius Promotion of Intestinal Stem Cell Activity in Hens Is Associated with Succinate-Induced Mitochondrial Energy Metabolism

Currently, the regulation of Lactobacillus on intestinal stem cells (ISCs) attracts broad attention, but their active ingredients and the underlying mechanism are worthy of further study. Previously, host intestinal commensal bacteria were verified to drive the differentiation of ISCs. In this study, the strong bacteriostatic activity of Lactobacillus salivarius and Lactobacillus agilis were illustrated, and the components (supernatant, precipitation) of L. salivarius or L. agilis were further demonstrated to decrease the differentiation of ISCs in vivo. Interestingly, antibiotics feeding decreased ISCs differentiation in vivo as well. However, the administration of L. salivarius supernatant following antibiotics feeding was shown to promote ISCs differentiation dramatically when compared with the antibiotics feeding group, indicating that some active ingredients existed in its supernatant to promote ISCs activity. Strikingly, in vitro, the treatment of L. salivarius supernatant was further confirmed to promote the intestinal organoids' size, budding, and LGR5 expression. Next, the metabolomics analysis of Lactobacilli' supernatants suggested that succinate might be a crucial metabolite to promote ISCs activity. Further, the succinate treatment in vitro (1000 μM) and in vivo (50 mM) was confirmed to enhance the expression of LGR5 and PCNA. SLC13A3 (a sodium/dicarboxylate cotransporter) was detected in the intestinal organoids and demonstrated to transport succinate into ISCs, as confirmed by the contact of FITC-succinate with ISCs nucleus. Subsequently, high mitochondrial membrane potential and reactive oxygen species levels appeared in the intestinal organoids upon succinate treatment. Collectively, the promotion of L. salivarius on ISCs activity is associated with succinate-induced mitochondrial energy metabolism. IMPORTANCE In our previous study, Lactobacillus salivarius and Lactobacillus agilis were demonstrated to regulate intestinal stem cell activity in hens, but their active ingredients and the underlying mechanism remain unclear. In this study, L. salivarius supernatant was shown to directly promote intestinal stem cell activity. Furthermore, the succinate (a critical metabolite of L. salivarius) was screened out to promote intestinal stem cell activity. Moreover, the succinate was confirmed to enter intestinal stem cells and induce high mitochondrial energy metabolism, finally promoting intestinal stem cell activity. These findings will advance uncovering the mechanism by which Lactobacillus regulate intestinal stem cell activity in chickens.

Lactobacillus salivarius Promotion of Intestinal Stem Cell Activity in Hens Is Associated with Succinate-Induced Mitochondrial Energy Metabolism

Currently, the regulation of Lactobacillus on intestinal stem cells (ISCs) attracts broad attention, but their active ingredients and the underlying mechanism are worthy of further study. Previously, host intestinal commensal bacteria were verified to drive the differentiation of ISCs. In this study, the strong bacteriostatic activity of Lactobacillus salivarius and Lactobacillus agilis were illustrated, and the components (supernatant, precipitation) of L. salivarius or L. agilis were further demonstrated to decrease the differentiation of ISCs in vivo. Interestingly, antibiotics feeding decreased ISCs differentiation in vivo as well. However, the administration of L. salivarius supernatant following antibiotics feeding was shown to promote ISCs differentiation dramatically when compared with the antibiotics feeding group, indicating that some active ingredients existed in its supernatant to promote ISCs activity. Strikingly, in vitro, the treatment of L. salivarius supernatant was further confirmed to promote the intestinal organoids' size, budding, and LGR5 expression. Next, the metabolomics analysis of Lactobacilli' supernatants suggested that succinate might be a crucial metabolite to promote ISCs activity. Further, the succinate treatment in vitro (1000 μM) and in vivo (50 mM) was confirmed to enhance the expression of LGR5 and PCNA. SLC13A3 (a sodium/dicarboxylate cotransporter) was detected in the intestinal organoids and demonstrated to transport succinate into ISCs, as confirmed by the contact of FITC-succinate with ISCs nucleus. Subsequently, high mitochondrial membrane potential and reactive oxygen species levels appeared in the intestinal organoids upon succinate treatment. Collectively, the promotion of L. salivarius on ISCs activity is associated with succinate-induced mitochondrial energy metabolism. IMPORTANCE In our previous study, Lactobacillus salivarius and Lactobacillus agilis were demonstrated to regulate intestinal stem cell activity in hens, but their active ingredients and the underlying mechanism remain unclear. In this study, L. salivarius supernatant was shown to directly promote intestinal stem cell activity. Furthermore, the succinate (a critical metabolite of L. salivarius) was screened out to promote intestinal stem cell activity. Moreover, the succinate was confirmed to enter intestinal stem cells and induce high mitochondrial energy metabolism, finally promoting intestinal stem cell activity. These findings will advance uncovering the mechanism by which Lactobacillus regulate intestinal stem cell activity in chickens.

Lactobacillus salivarius and Lactobacillus agilis feeding regulates intestinal stem cells activity by modulating crypt niche in hens

Previously, we found that Lactobacillus salivarius, Lactobacillus agilis, and Lactobacillus aviarius were associated with excellent egg nutrition in native chicken. Next, the optimal Lactobacillus combination is worth studying. Here, a total of 120 HyLine hens (30 hens per group contained 3 replicate cells, 10 hens/cell) in the laying peak period were randomly divided into (1) control, (2) L. salivarius + L. agilis, (3) L. salivarius + L. aviarius, and (4) L. agilis + L. aviarius groups, fed with diet only or with corresponding Lactobacilli (10⁸ colony-forming units/hen/day) for 30 days. As a result, L. salivarius + L. agilis feeding could (1) improve egg-laying rate, egg weight, and albumen's amino acid levels; (2) increase Lactobacillus abundance, decrease Escherichia coli abundance, upregulate the tryptophan metabolism pathway-related molecules, and downregulate the primary bile acid biosynthesis pathway-related molecules in intestinal contents; and (3) upregulate oxidative-phosphorylation pathway-related genes, reactive oxygen species levels, and mRNA abundance of Wnt3a, Dll1, Lgr5, CCDN1, and CDK2 in the crypt. Collectively, L. salivarius + L. agilis feeding in hens could improve intestinal microflora and metabolism profile, promote crypt's local energy metabolism and reactive oxygen species levels, and thus enhance Paneth cells and intestinal stem cells activity.Key points• Lactobacilli co-feeding could improve laying performance and egg nutrition.• Lactobacilli co-feeding could improve intestinal microflora and metabolism profile.• Lactobacilli co-feeding could enhance Paneth cells and intestinal stem cells activity.