Strategies to modulate the intestinal microbiota and their effects on nutrient utilization, performance, and health of poultry

The impact of different levels of functional oil supplementation in combination with salinomycin on growth performance and intestinal microbiota of broilers undergoing Eimeria challenge: An analysis of dynamics

The effect of salinomycin sodium alone and in combination with functional oils on performance and microbiota of broiler infected Eimeria were evaluated. 512 broilers were randomly assigned to 4 treatments (8 replicates, 16 birds/pen): a Control group (any additives); Ionophore group: salinomycin supplementation at 66 ppm (SS66); Ionophore +0.075% Functional oil (FO) group (SS66 + FO supplementation at 750 ppm); and Ionophore +0.10% FO group (SS66 + FO supplementation at 1000 ppm). At 14 days of age, birds were gavaged with 1 mL of a saline solution containing sporulated oocysts of E. tenella, E. acervulina and E. maxima. Performance indices were measured weekly. At 28 days, intestinal content was collected for microbiota analysis. Broilers of Control group presented the worst performance indices. Broilers of Ionophore + FO (0.075% and 0.10%) groups exhibited a higher BW at 28 days of age. The supplementation of Ionophore +0.075% FO resulted in a higher relative proportion of Firmicutes and a lower proportion of Actinobacteria in the ileum-jejunum. Lactobacillaceae was the dominant family in the jejunal, and ileal microbiotas of broilers fed diets supplemented with Ionophore, Ionophore +0.075% FO and Ionophore +0.10% FO. The supplementation of ionophore yielded higher numbers of Lactobacillaceae, Enterobactereaceae and Cloritridiaceae in the cecal. Ionophore associated with FO controlled the Lactobacillaceae, Enterobactereaceae and Cloritridiaceae families present in the cecum. Therefore, the combination of salinomycin with functional oil showed synergistic effect on performance and modulation of intestinal microbiota of broilers challenged with Eimeria.

Diet xylo-oligosaccharide supplementation improves growth performance, immune function, and intestinal health of broilers

The effects of xylo-oligosaccharides (XOS) on broiler growth performance, immune function, and intestinal health were investigated. A total of 540 one-d-old Arbor Acres Plus broilers were randomly divided into 5 groups with 6 replicates per group and 18 chickens per replicate. Broilers in the control (CON) group received a corn-soybean meal based basal diet, those in the antibiotics (ANT) group received the basal diet plus 500 mg/kg oxytetracycline, and those in XOS groups received the basal diet plus 150, 300, or 450 mg/kg XOS. Compared with CON, the body weight at 42 d and average daily gain from 1 to 42 d were significantly increased in the 150, 450 mg/kg XOS-added and ANT groups (P = 0.018), and the relative expression of claudin-1 and ZO-1 mRNA in the ileum was significantly higher in the 300 and 450 mg/kg XOS-added groups (P < 0.001). The feed conversion ratios (P < 0.001) and abdominal fat rates (P = 0.012) of broilers from 1 to 42 d of age were significantly lower in all XOS-added groups than in the control group. Splenic index (P = 0.036) and bursa of Fabricius index (P = 0.009) were significantly better in the ANT group and each XOS-added group than in the control group. Compared to CON and ANT, serum IgA (P = 0.007) and IgG (P = 0.002) levels were significantly higher in the 300 mg/kg XOS-added group, and the relative abundance of short-chain fatty acid-producing genera (Alistipes) was also significantly higher (P < 0.001). Meanwhile, ileal villus height (P < 0.001) and ratio of villus height to crypt depth (V:C) (P = 0.001) were significantly increased in XOS-added broilers. In analysis of relationships between cecal microbes and the physical barrier of the gut, [Ruminococcus]_torques_group was positively correlated with mRNA expression of ileal ZO-1 and claudin-1 (P < 0.05), and Bacteroides was positively correlated with increased ileal villus height and V:C (P < 0.05). Overall, XOS addition to broiler diets improved growth performance, promoted intestinal health by enhancing intestinal barrier function and regulating cecal microbiota diversity, and had positive effects on immunity.

Dietary Supplementation of Brevibacillus laterosporus S62-9 Improves Broiler Growth and Immunity by Regulating Cecal Microbiota and Metabolites

Brevibacillus laterosporus has been added as a direct-fed microbiota to chicken. Yet, few studies have reported the effects of B. laterosporus on broiler growth and gut microbiota. The aim of this study was to evaluate the effects of B. laterosporus S62-9 on growth performance, immunity, cecal microbiota, and metabolites in broilers. A total of 160 1-day-old broilers were randomly divided into S62-9 and control groups, with or without 106 CFU/g B. laterosporus S62-9 supplementation, respectively. During the 42 days feeding, body weight and feed intake were recorded weekly. Serum was collected for immunoglobulin determination, and cecal contents were taken for 16S rDNA analysis and metabolome at Day 42. Results indicated that the broilers in S62-9 group showed an increase in body weight of 7.2% and 5.19% improvement in feed conversion ratio compared to the control group. The B. laterosporus S62-9 supplementation promoted the maturation of immune organs and increased the concentration of serum immunoglobulins. Furthermore, the α-diversity of cecal microbiota was improved in the S62-9 group. B. laterosporus S62-9 supplementation increased the relative abundance of beneficial bacteria including Akkermansia, Bifidobacterium, and Lactobacillus, while decreased the relative abundance of pathogens including Klebsiella and Pseudomonas. Untargeted metabolomics revealed that 53 differential metabolites between the two groups. The differential metabolites were enriched in 4 amino acid metabolic pathways, including arginine biosynthesis and glutathione metabolism. In summary, B. laterosporus S62-9 supplementation could improve the growth performance and immunity through the regulation of gut microbiota and metabolome in broilers.

Microbial contamination pathways in a poultry abattoir provided clues on the distribution and persistence of Arcobacter spp

The consumption of contaminated poultry meat is a significant threat for public health, as it implicates in foodborne pathogen infections, such as those caused by Arcobacter. The mitigation of clinical cases requires the understanding of contamination pathways in each food process and the characterization of resident microbiota in the productive environments, so that targeted sanitizing procedures can be effectively implemented. Nowadays these investigations can benefit from the complementary and thoughtful use of culture- and omics-based analyses, although their application in situ is still limited. Therefore, the 16S-rRNA gene-based sequencing of total DNA and the targeted isolation of Arcobacter spp. through enrichment were performed to reconstruct the environmental contamination pathways within a poultry abattoir, as well as the dynamics and distribution of this emerging pathogen. To that scope, broiler's neck skin and caeca have been sampled during processing, while environmental swabs were collected from surfaces after cleaning and sanitizing. Metataxonomic survey highlighted a negligible impact of fecal contamination and a major role of broiler's skin in determining the composition of the resident abattoir microbiota. The introduction of Arcobacter spp. in the environment was mainly conveyed by this source rather than the intestinal content. Arcobacter butzleri represented one of the most abundant species and was extensively detected in the abattoir by both metataxonomic and enrichment methods, showing higher prevalence than other more thermophilic Campylobacterota. In particular, Arcobacter spp. was recovered viable in the plucking sector with high frequency, despite the adequacy of the sanitizing procedure.IMPORTANCEOur findings have emphasized the persistence of Arcobacter spp. in a modern poultry abattoir and its establishment as part of the resident microbiota in specific environmental niches. Although the responses provided here are not conclusive for the identification of the primary source of contamination, this biogeographic assessment underscores the importance of monitoring Arcobacter spp. from the early stages of the production chain with the integrative support of metataxonomic analysis. Through such combined detection approaches, the presence of this pathogen could be soon regarded as hallmark indicator of food safety and quality in poultry slaughtering.

The Role of Intestinal Microbiota and Probiotics Supplementation in Multiple Sclerosis Management

Multiple sclerosis (MS) is a neurological autoimmune disorder predominantly afflicting young adults. The etiology of MS is intricate, involving a variety of environmental and genetic factors. Current research increasingly focuses on the substantial contribution of gut microbiota in MS pathogenesis. The commensal microbiota resident within the intestinal milieu assumes a central role within the intricate network recognized as the gut-brain axis (GBA), wielding beneficial impact in neurological and psychological facets. As a result, the modulation of gut microbiota is considered a pivotal aspect in the management of neural disorders, including MS. Recent investigations have unveiled the possibility of using probiotic supplements as a promising strategy for exerting a positive impact on the course of MS. This therapeutic approach operates through several mechanisms, including the reinforcement of gut epithelial integrity, augmentation of the host's resistance against pathogenic microorganisms, and facilitation of mucosal immunomodulatory processes. The present study comprehensively explains the gut microbiome's profound influence on the central nervous system (CNS). It underscores the pivotal role played by probiotics in forming the immune system and modulating neurotransmitter function. Furthermore, the investigation elucidates various instances of probiotic utilization in MS patients, shedding light on the potential therapeutic advantages afforded by this intervention.

Metagenomic insights into the relationship between intestinal flora and residual feed intake of meat ducks

In this study, we sought to determine the effects of intestinal flora on the feed efficiency of meat ducks by evaluating the correlation between intestinal flora and residual feed intake. The F2 generation of Cherry Valley ducks × Runzhou Crested White ducks was used as the study subjects, and feed consumption being recorded from d 21 to 42. RFI was calculated based on growth performance, and 20 low RFI and 20 high RFI ducks were randomly selected to characterize the effect of RFI on growth performance. To analyze the intestinal flora affecting RFI, 16s rDNA sequencing was performed on the contents of 5 intestinal segments from the HR and LR groups, and macrogenomic sequencing was performed on the cecal contents. Feed intake, average daily feed intake, feed conversion ratio, and residual feed intake were lower in low RFI. Analysis of the intestinal flora revealed the cecum to be more highly enriched in the carbohydrate metabolism pathway and less enriched with potentially pathogenic taxa than the other assessed intestinal regions. Further analysis of the cecal microbiota identified nine significantly differentially enriched intestinal flora. In this study, we accordingly identified a basis for the mechanisms underlying the effects of the intestinal flora on meat duck feed efficiency.

In vitro evaluation of the application of an optimized xylanase cocktail for improved monogastric feed digestibility

Xylanases from glycoside hydrolase (GH) families 10 and 11 are common feed additives for broiler chicken diets due to their catalytic activity on the nonstarch polysaccharide xylan. This study investigated the potential of an optimized binary GH10 and GH11 xylanase cocktail to mitigate the antinutritional effects of xylan on the digestibility of locally sourced chicken feed. Immunofluorescence visualization of the activity of the xylanase cocktail on xylan in the yellow corn of the feed showed a substantial collapse in the morphology of cell walls. Secondly, the reduction in the viscosity of the digesta of the feed by the cocktail showed an effective degradation of the soluble fraction of xylan. Analysis of the xylan degradation products from broiler feeds by the xylanase cocktail showed that xylotriose and xylopentaose were the major xylooligosaccharides (XOS) produced. In vitro evaluation of the prebiotic potential of these XOS showed that they improved the growth of the beneficial bacteria Streptococcus thermophilus and Lactobacillus bulgaricus. The antibacterial activity of broths from XOS-supplemented probiotic cultures showed a suppressive effect on the growth of the extraintestinal infectious bacterium Klebsiella pneumoniae. Supplementing the xylanase cocktail in cereal animal feeds attenuated xylan's antinutritional effects by reducing digesta viscosity and releasing entrapped nutrients. Furthermore, the production of prebiotic XOS promoted the growth of beneficial bacteria while inhibiting the growth of pathogens. Based on these effects of the xylanase cocktail on the feed, improved growth performance and better feed conversion can potentially be achieved during poultry rearing.

Investigating antibiotic free feed additives for growth promotion in poultry: effects on performance and microbiota

The poultry industry is evolving towards antibiotic-free production to meet market demands and decelerate the increasing spread of the antimicrobial resistance. The growing need for antibiotic free products has challenged producers to decrease or completely stop using antimicrobials as feed supplements in broiler diet to improve feed efficiency, growth rate, and intestinal health. Natural feed additives (e.g., probiotics and phytobiotics) are promising alternatives to substitute antimicrobial growth promoters. The goal of our study was to characterize the effects of a Probiotic and an Essential Oils blend on broilers' performance and perform a time-series analysis to describe their excreta microbiome. A total of 320 Cobb 500 (1-day-old) chicks were raised for 21 d in 32 randomly allocated cages. Treatments consisted of 4 experimental diets: a basal diet, and a basal diet mixed with an Antibiotic (bacitracin methylene disalicylate), an essential oils blend (oregano oil, rosemary, and red pepper), or a Probiotic (Bacillus subtilis). Body weight (on 1, 10, and 21d), and feed intake (10d and 21d) were recorded and feed conversion ratio was calculated. Droppings were collected daily (1-21d) to characterize broilers' excreta microbiota by targeted sequencing of the bacterial 16S rRNA gene. The Probiotic significantly improved feed conversion ratio for starter phase 1 to 10d (P = 0.03), grower phase 10 to 21d (P = 0.05), and total period 1 to 21d (P = 0.01) compared to the Antibiotic. Feed supplements did not affect alpha diversity but did impact microbial beta diversity (P < 0.01). Age also impacted microbiome turnover as differences in alpha and beta diversity were detected. Furthermore, when compared to the basal diet, the probiotic and antibiotic significantly impacted relative abundance of Bifidobacterium (log2 fold change -1.44, P = 0.03), Intestinimonas (log2 fold change 0.560, P < 0.01) and Ligilactobacillus (log2 fold change -1.600, P < 0.01). Overall, Probiotic supplementation but not essential oils supplementation positively impacted broilers' growth performance by directly causing directional shifts in broilers' excreta microbiota structure.

Pu-erh tea theabrownin improves the ovarian function and gut microbiota in laying hens

Studies have reported that theabrownin can moderate the lipid metabolism and intestinal microbiota, thereby affecting the health of humans and model animals, however the research on laying hens is scarce. The present study aimed to investigate the effects of dietary theabrownin supplementation on lipid metabolism, microbial composition and ovarian function in laying hens. A total of 80 laying hens (25 wk of age) were fed with normal diet (CON) and normal diet +100 mg/kg theabrownin (PT group) for 12 wk. The results showed that the addition of theabrownin enhanced villus height of duodenum and decreased crypt depth of jejunum (P < 0.05). At the same time, compared with CON, the concentration of IL-6 and the mRNA expression of IL-1β and IL-6 were decreased significantly in PT group (P < 0.05). Dietary theabrownin reduced the concentration of total cholesterol and glycerol, while decreased lipid droplet optical density in liver (P < 0.05). Compared with CON group, the mRNA expression of PPARγ, HMG-CoAS, ACC were down-regulated and the mRNA expression of CYP8B1 was up-regulated in PT group (P < 0.05). The ACE, Chao1 and Observed_species indexes in cecum microbiota were increased by PT group intervention (P < 0.05). Dietary PT supplementation enhanced the relative abundance of Firmicutes (phylum), Lactobacillus (genus) and the Firmicutes to Bacteroidetes ratio, and reduced the relative abundance of Bacteroidetes (phylum) in cecum (P < 0.05). The organic acids and its derivatives were up-regulated by theabrownin intervention in serum metabolites (P < 0.05). Dietary theabrownin supplementation resulted in higher mRNA expression of Bcl-2 and SIRT1 in ovary and increased the concentration of estradiol in serum (P < 0.05). These discovering indicated that dietary theabrownin supplementation enhanced the intestinal function and influenced serum metabolism by improving intestinal morphology, microbiota community structure and reducing the concentration and expression of inflammatory cytokines in intestine. Dietary theabrownin reduced hepatic lipid deposition and it also decreased the cell apoptosis rate to improve ovarian function and egg weight which were associated with the SIRT1 pathway.

Differences in the intestinal microbiota and association of host metabolism with hair coat status in cattle

Introduction

The hair coat status of cattle serves as an easily observed indicator of economic value in livestock production; however, the underlying mechanism remains largely unknown. Therefore, the objective of the current study was to determine differences in the intestinal microbiota and metabolome of cattle based on a division of with either slick and shining (SHC) or rough and dull (MHC) hair coat in Simmental cows.

Methods

Eight SHC and eight MHC late-pregnancy Simmental cows (with similar parities, body weights, and body conditions) were selected based on their hair coat status, and blood samples (plasma) from coccygeal venipuncture and fecal samples from the rectum were collected. The intestinal microbiota (in the fecal samples) was characterized by employing 16S rRNA gene sequencing targeting the V3-V4 hypervariable region on the Illumina MiSeq PE300 platform, and plasma samples were subjected to LC-MS/MS-based metabolomics with Progenesis QI 2.3. Plasma macromolecular metabolites were examined for differences in the metabolism of lipids, proteins, mineral elements, and hormones.

Results

Notable differences between the SHC and MHC groups related to host hair coat status were observed in the host metabolome and intestinal microbiota (P < 0.05). The host metabolome was enriched in histidine metabolism, cysteine and methionine metabolism, and purine metabolism in the SHC group, and the intestinal microbiota were also enriched in histidine metabolism (P < 0.05). In the MHC group, the symbiotic relationship transitioned from cooperation to competition in the MHC group, and an uncoupling effect was present in the microbe-metabolite association of intestine microbiota-host interactions. The hubs mediating the relationships between intestinal microbiota and plasma metabolites were the intestinal bacterial genus g__norank_f__Eubacterium_coprostanoligenes_group, plasma inosine, triiodothyronine, and phosphorus, which could be used to differentiate cows' hair coat status (P < 0.05).

Conclusion

Overall, the present study identified the relationships between the features of the intestinal microbiota and host hair coat status, thereby providing evidence and a new direction (intestine microbiota-host interplay) for future studies aimed at understanding the hair coat status of cattle.

Intestinal microbiome profiles in broiler chickens raised without antibiotics exhibit altered microbiome dynamics relative to conventionally raised chickens

The present study was undertaken to profile and compare the cecal microbial communities in conventionally (CONV) grown and raised without antibiotics (RWA) broiler chickens. Three hundred chickens were collected from five CONV and five RWA chicken farms on days 10, 24, and 35 of age. Microbial genomic DNA was extracted from cecal contents, and the V4-V5 hypervariable regions of the 16S rRNA gene were amplified and sequenced. Analysis of 16S rRNA sequence data indicated significant differences in the cecal microbial diversity and composition between CONV and RWA chickens on days 10, 24, and 35 days of age. On days 10 and 24, CONV chickens had higher richness and diversity of the cecal microbiome relative to RWA chickens. However, on day 35, this pattern reversed such that RWA chickens had higher richness and diversity of the cecal microbiome than the CONV groups. On days 10 and 24, the microbiomes of both CONV and RWA chickens were dominated by members of the phylum Firmicutes. On day 35, while Firmicutes remained dominant in the RWA chickens, the microbiome of CONV chickens exhibited am abundance of Bacteroidetes. The cecal microbiome of CONV chickens was enriched with the genus Faecalibacterium, Pseudoflavonifractor, unclassified Clostridium_IV, Bacteroides, Alistipes, and Butyricimonas, whereas the cecal microbiome of RWA chickens was enriched with genus Anaerofilum, Butyricicoccu, Clostridium_XlVb and unclassified Lachnospiraceae. Overall, the cecal microbiome richness, diversity, and composition were greatly influenced by the management program applied in these farms. These findings provide a foundation for further research on tailoring feed formulation or developing a consortium to modify the gut microbiome composition of RWA chickens.

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.

Antimicrobial stewardship hindered by inadequate biosecurity and biosafety practices, and inappropriate antibiotics usage in poultry farms of Nepal-A pilot study

Nepal's poultry industry has experienced remarkable growth in the last decade, but farm biosafety and biosecurity measures are often overlooked by farmers. As a result, farms often suffer from sporadic and regular outbreaks of many diseases, impacting production and creating public health challenges. Poor management practices, including overuse of antibiotics for prophylaxis and therapeutics, can enhance the spread of poultry diseases by propagating antimicrobial resistance (AMR) that is threatening poultry and human health. We assessed biosafety, biosecurity risks and AMR stewardship in sixteen poultry farms located in four districts: Ramechhap, Nuwakot, Sindhupalchowk, and Kavre. Risk assessment and AMR stewardship evaluation questionnaires were administered to formulate biosafety and biosecurity compliance matrix (BBCM). Risk assessment checklist assessed facility operations, personnel and standard operating procedures, water supply, cleaning and maintenance, rodent/pest control and record keeping. Oral and cloacal samples from the poultry were collected, pooled, and screened for eight poultry pathogens using Polymerase Chain Reaction (PCR) tests. Based on BBCM, we identified the highest BBCM score of 67% obtained by Sindhupalchowk farm 4 and the lowest of 12% by Kavre farm 3. Most of the farms (61.6%) followed general poultry farming practices, only half had clean and well-maintained farms. Lowest scores were obtained for personnel safety standard (42.4%) and rodent control (3.1%). At least one of the screened pathogens were detected in all farms. Mycoplasma gallisepticum was the most common pathogen detected in all but three farms, followed by Mycoplasma synoviae. More than half of the farmers considered AMR a threat, over 26% of them used antibiotics as a preventive measure and 81% did not consider withdrawal period for antibiotics prior to processing of their meat products. Additionally, antibiotics classified as "Watch" and "Restrict" by the WHO were frequently used by the farmers to treat bacterial infections in their farms.

Live black soldier fly (Hermetia illucens) larvae in feed for laying hens: effects on hen gut microbiota and behavior

This study examined the effects of including live black soldier fly (BSF, Hermetia illucens) larvae in the diet of laying hens on gut microbiota, and the association between microbiota and fearfulness. A total of 40 Bovans White laying hens were individually housed and fed 1 of 4 dietary treatments that provided 0, 10, 20%, or ad libitum daily dietary portions of live BSF larvae for 12 wk. Cecum microbiota was collected at the end of the experiment and sequenced. Behavioral fear responses to novel objects and open field tests on the same hens were compared against results from gut microbiota analyses. The results showed that the bacteria genera Enterococcus, Parabacteroides, and Ruminococcus torques group were positively associated with increased dietary portion of live larvae, while Lactobacillus, Faecalibacterium, Bifidobacterium, Subdoligranulum, and Butyricicoccus were negatively associated with larvae in the diet. Inclusion of larvae did not affect fear behavior, but the relative abundance of Lachnospiraceae CHKCI001 and Erysipelatoclostridium was associated with fear-related behaviors. Further studies are needed to determine whether the change in gut microbiota affects fearfulness in the long-term.

Comparative Assessment of the Antibacterial and Antibiofilm Actions of Benzalkonium Chloride, Erythromycin, and L(+)-Lactic Acid against Raw Chicken Meat Campylobacter spp. Isolates

Campylobacter spp. are significant zoonotic agents, which cause annually millions of human cases of foodborne gastroenteritis worldwide. Their inclusion in biofilms on abiotic surfaces seems to play a pivotal role in their survival outside of the host, growth, and spread. To successfully mitigate the risks that arise with these bacteria, it is crucial to decrease their prevalence within the food production chain (from farm to the table), alongside the successful treatment of the resulting illness, known as campylobacteriosis. For this, the use of various antimicrobial agents remains actively in the foreground. A general-purpose biocide and cationic surfactant (benzalkonium chloride; BAC), a widely used macrolide antibiotic (erythromycin; ERY), and a naturally occurring organic acid (L(+)-lactic acid; LA) were comparatively evaluated in this work for their potential to inhibit both the planktonic and biofilm growth of 12 selected Campylobacter spp. (of which, seven were C. jejuni and five were C. coli) raw chicken meat isolates, all grown in vitro as monocultures. The inhibitory action of LA was also studied against four mixed-culture Campylobacter biofilms (each composed of three different isolates). The results showed that the individual effectiveness of the agents varied significantly depending on the isolate, growth mode (planktonic, biofilm), intercellular interactions (monocultures, mixed cultures), and the growth medium used (with special focus on blood presence). Thus, BAC exhibited minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs), and minimum biofilm inhibitory concentrations (MBICs) that ranged from 0.5 to 16 μg/mL. Interestingly enough, these values varied widely from 0.25 to 1024 μg/mL for ERY. Concerning LA, the MICs, MBCs, and MBICs varied from 1024 to 4096 μg/mL, with mixed-culture biofilm formation always being more difficult to suppress when compared to biofilm monocultures. In addition, it was evident that intercellular interactions encountered within mixed-culture Campylobacter biofilms significantly influenced both the population dynamics and the tolerance of each consortium member to acid exposure. Overall, the findings of this study provide useful information on the comparative effectiveness of three well-known antimicrobial agents for the control of Campylobacter spp. under various growth modes (i.e., planktonic, biofilm, monocultures, mixed cultures) that could potentially be encountered in food production and clinical settings.

Bacillus amyloliquefaciens Probiotics Mix Supplementation in a Broiler Leaky Gut Model

The supplementation of antimicrobial growth promoters (AGPs) has been banned in many countries because of the emergence of antimicrobial-resistant pathogens in poultry products and the environment. Probiotics have been broadly studied and demonstrated as a promising AGP substitute. Our study is centred on the effects of a multi-strain Bacillus-based probiotic product on broiler production performance and gut microbial profile in a dexamethasone-induced leaky gut challenge. Two hundred and fifty-six broiler chicks were hatched and randomly assigned into four groups (wheat-soybean meal basal diet (BD) = non-supplemented control (C), BD supplemented with dexamethasone in week 4 (CD), BD containing a probiotic from day one (P), and BD containing a probiotic from day one and supplemented with dexamethasone during challenge week 4 (PD)). The production performance and caecal, gizzard, jejunal lumen and jejunal mucosa swab microbiota were studied by 16S rRNA gene sequencing. The Bacillus probiotic product significantly improved production performance and altered caecal gut microbiota (p ≤ 0.05), but no significant impact on microbiota was observed in other gut sections.

Dynamic effects of black soldier fly larvae meal on the cecal bacterial microbiota and prevalence of selected antimicrobial resistant determinants in broiler chickens

BACKGROUND

We had earlier described the growth-promoting and -depressive effects of replacing soybean meal (SBM) with low (12.5% and 25%) and high (50% and 100%) inclusion levels of black soldier fly larvae meal (BSFLM), respectively, in Ross x Ross 708 broiler chicken diets. Herein, using 16S rRNA gene amplicon sequencing, we investigated the effects of replacing SBM with increasing inclusion levels (0-100%) of BSFLM in broiler diets on the cecal bacterial community composition at each growth phase compared to broilers fed a basal corn-SBM diet with or without the in-feed antibiotic, bacitracin methylene disalicylate (BMD). We also evaluated the impact of low (12.5% and 25%) inclusion levels of BSFLM (LIL-BSFLM) on the prevalence of selected antimicrobial resistance genes (ARGs) in litter and cecal samples from 35-day-old birds.

RESULTS

Compared to a conventional SBM-based broiler chicken diet, high (50 to100%) inclusion levels of BSFLM (HIL-BSFLM) significantly altered the cecal bacterial composition and structure, whereas LIL-BSFLM had a minimal effect. Differential abundance analysis further revealed that the ceca of birds fed 100% BSFLM consistently harbored a ~ 3 log-fold higher abundance of Romboutsia and a ~ 2 log-fold lower abundance of Shuttleworthia relative to those fed a BMD-supplemented control diet at all growth phases. Transient changes in the abundance of several potentially significant bacterial genera, primarily belonging to the class Clostridia, were also observed for birds fed HIL-BSFLM. At the finisher phase, Enterococci bacteria were enriched in the ceca of chickens raised without antibiotic, regardless of the level of dietary BSFLM. Additionally, bacitracin (bcrR) and macrolide (ermB) resistance genes were found to be less abundant in the ceca of chickens fed antibiotic-free diets, including either a corn-SBM or LIL-BSFLM diet.

CONCLUSIONS

Chickens fed a HIL-BSFLM presented with an imbalanced gut bacterial microbiota profile, which may be linked to the previously reported growth-depressing effects of a BSFLM diet. In contrast, LIL-BSFLM had a minimal effect on the composition of the cecal bacterial microbiota and did not enrich for selected ARGs. Thus, substitution of SBM with low levels of BSFLM in broiler diets could be a promising alternative to the antibiotic growth promoter, BMD, with the added-value of not enriching for bacitracin- and macrolide-associated ARGs.

Chestnut Wood Tannins in Broiler Diets: Pharmacokinetics, Serum Levels during Rearing, and Intestinal Absorption Pattern of Gallic Acid

Studies on the bioavailability, serum levels, and absorption of hydrolyzable tannin compounds are lacking. In this study, we performed a pharmacokinetic trial, measured the serum levels of compounds in broilers that were reared with different feed added or not with tannins, and tested the digestibility of tannins throughout the intestinal tract. Only gallic acid and 4-O-methyl gallic acid were found in the serum. Moreover, gallic acid showed a 41.8% absolute oral bioavailability and a 72.3% relative bioavailability of gallic acid from chestnut extract compared to the standard. The rapid metabolization caused alternating serum levels during the day and night. These patterns were not affected by the feed type or the previous addition of tannins in the feed. The absorption and metabolization in the intestines occurred gradually throughout the intestinal tract. The latter was true for gallic acid as well as ellagic acid, which was not found in the serum. We can conclude that components from chestnut tannins are absorbed throughout all components of the intestinal tract and are eliminated quickly with little interaction from the feed and previous addition of tannins. Moreover, ellagic acid seems to be absorbed but would remain accumulated in the intestinal tissue or be metabolized by the microbiome.

Layer chicken microbiota: a comprehensive analysis of spatial and temporal dynamics across all major gut sections

BACKGROUND

The gut microbiota influences chicken health, welfare, and productivity. A diverse and balanced microbiota has been associated with improved growth, efficient feed utilisation, a well-developed immune system, disease resistance, and stress tolerance in chickens. Previous studies on chicken gut microbiota have predominantly focused on broiler chickens and have usually been limited to one or two sections of the digestive system, under controlled research environments, and often sampled at a single time point. To extend these studies, this investigation examined the microbiota of commercially raised layer chickens across all major gut sections of the digestive system and with regular sampling from rearing to the end of production at 80 weeks. The aim was to build a detailed picture of microbiota development across the entire digestive system of layer chickens and study spatial and temporal dynamics.

RESULTS

The taxonomic composition of gut microbiota differed significantly between birds in the rearing and production stages, indicating a shift after laying onset. Similar microbiota compositions were observed between proventriculus and gizzard, as well as between jejunum and ileum, likely due to their anatomical proximity. Lactobacillus dominated the upper gut in pullets and the lower gut in older birds. The oesophagus had a high proportion of Proteobacteria, including opportunistic pathogens such as Gallibacterium. Relative abundance of Gallibacterium increased after peak production in multiple gut sections. Aeriscardovia was enriched in the late-lay phase compared to younger birds in multiple gut sections. Age influenced microbial richness and diversity in different organs. The upper gut showed decreased diversity over time, possibly influenced by dietary changes, while the lower gut, specifically cecum and colon, displayed increased richness as birds matured. However, age-related changes were inconsistent across all organs, suggesting the influence of organ-specific factors in microbiota maturation.

CONCLUSION

Addressing a gap in previous research, this study explored the microbiota across all major gut sections and tracked their dynamics from rearing to the end of the production cycle in commercially raised layer chickens. This study provides a comprehensive understanding of microbiota structure and development which help to develop targeted strategies to optimise gut health and overall productivity in poultry production.

Effects of microalgae, with or without xylanase supplementation, on serum immunoglobulins, cecal short-chain fatty acids, microbial diversity, and metabolic pathways of broiler chickens

Modern broilers are highly susceptible to environmental and pathogenic threats, leading to gut disorders and poor nutrient utilization if not managed properly. Nutritional programming using several feedstuffs and coproducts to manage gut health has been studied. This study used microalgae as a functional compound and xylanase enzyme in broilers' diets as a strategy to manage gut health. A total of 162 one-day-old unsexed Cobb 500 broiler chicks were randomly assigned to 1 of the 3 dietary treatments: a) corn-soybean meal-based control diet (CON), b) 3% microalgae (MAG), and c) MAG with xylanase enzyme (MAG+XYN). The chicks were reared for 35 days (d) on a floor pen system maintaining standard environment conditions to evaluate the effects of microalgae, with or without xylanase supplementation, on serum immunoglobulins, cecal short-chain fatty acids (SCFA) production, cecal microbial diversity, and metabolic pathways. No significant differences were found for serum immunoglobulin and cecal SCFA among the treatment groups (P > 0.05). Relative microbial abundance at the genus level showed that MAG and MAG+XYN groups had a diverse microbial community on d 3 and d 35. However, no bacterial genus had a significant difference (P > 0.05) in their relative abundance on d 3, but 16 genera showed significant differences (P < 0.05) in their relative abundance among the dietary treatments on d 35. Most of these bacteria were SCFA-producing bacteria. Moreover, MAG and MAG+XYN-fed broilers had better responses than CON groups for metabolic pathways (D-mannose degradation, pectin degradation I and II, β-1-4-mannan degradation, tetrahydrofolate biosynthesis, glutathione biosynthesis, glutathione-peroxide redox reactions, lactate fermentation to propionate, acetate, and hydrogen, etc.) both on d 3 and d 35. The results suggest that using microalgae, with or without xylanase, had no statistical impact on serum immunoglobulins and cecal SCFA production in broilers. However, an improvement in the cecal microbial diversity and metabolic pathways, which are essential indicators of gut health and nutrient utilization, was observed. Most of the improved metabolic pathways were related to fiber utilization and oxidative stress reduction.

Dietary strategies can increase cloacal endotoxin levels and modulate the resident microbiota in broiler chickens

Endotoxins released from poultry feces have been associated with impaired human health. Because endotoxins are released from gram-negative intestinal bacteria, it was hypothesized that dietary strategies may influence endotoxin excretion via modulation of gut microbiota. We therefore tested dietary strategies that could potentially reduce cloacal endotoxin levels in broiler chickens. One-day-old male Ross 308 (N = 1,344) broilers were housed in 48 pens (N = 8 pens/treatment, 28 chickens per pen) and fed 1 of 6 diets for 35 days (d) in a 3-phase feeding program: a basic diet (CON) that served as the reference diet, or basic diet supplemented with butyrate (BUT), inulin (INU), medium-chain fatty acids (MCFA) or Original XPC™LS (XPC), or a high-fiber-low-protein (HF-LP) diet. A significant (P < 0.05) increase in cloacal endotoxin concentration at d 35 was observed in BUT as compared to CON. Analysis of cloacal microbiota showed a trend (P < 0.07) for a higher gram-negative/gram-positive ratio and for a higher relative abundance of gram-negative bacteria at d 35 (P ≤ 0.08) in BUT and HF-LP as compared to CON. A significant (P < 0.05) increase in average daily gain (ADG) and improved feed conversion ratio (P < 0.05) were observed in MCFA during the grower phase (d 14-28), and a significant (P < 0.05) increase in average daily feed intake (ADFI) was observed in MCFA during d 0 to 28. Broilers fed HF-LP had a significantly (P < 0.05) higher FCR and lower ADG throughout the rearing period. No treatment effects were found on footpad dermatitis, but BUT had worst hock burn scores at d 35 (P < 0.01) and MCFA had worst cleanliness scores at d 21 but not at d 35 (treatment*age P < 0.05), while INU had better cleanliness as compared to CON at d 35 (P < 0.05). In conclusion, especially BUT and HF-LP were able to modulate resident microbiota and BUT also increased cloacal endotoxin levels, which was opposite to our hypothesis. The present study indicates that cloacal endotoxin release can be affected by the diet but further study is needed to find dietary treatments that can reduce cloacal endotoxin release.

Research Note: Effect of dietary xylo-oligosaccharide on growth performance, intestinal histomorphology, and specific cecal bacteria in broiler chickens

This study was conducted to evaluate the prebiotic effect of xylo-oligosaccharide (XOS) supplemented in a corn-soybean meal (SBM) based conventional diet on growth performance, intestinal histomorphology, and quantification of specific bacteria in the ceca of broilers. A total of 240 d of hatch Cobb 500 male broiler chicks were randomly assigned to 4 dietary treatments (corn-SBM-based control diet) containing 0, 0.05, 0.1, and 0.2% XOS. The broilers were raised for 21 d in 6 replicate cages, each containing 10 birds. Growth performance parameters were obtained weekly. Additionally, small intestinal tissues were collected to evaluate histomorphometry and whole ceca were collected to quantify bacterial populations on D21. The results showed that inclusion of XOS has similar body weight (BW), body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR) as the control group during the 21-day study. The results further indicate a tendency for the jejunum villus to crypt ratio (VH:CD) to increase in birds given 0.05 and 0.2% XOS (P = 0.08). Cecal bacteria quantification showed a linear increase in Bifidobacterium with increasing XOS levels (P < 0.0001) and a decrease Clostridium perfringens levels compared to birds fed the control diet (P < 0.0001). However, there were no differences in the total counts of Lactobacillus and E. coli. Together these results showed that while there were no differences in growth parameters up to 21 d, the histomorphology findings and the increase in Bifidobacterium, along with the reduction in C. perfringens observed in the XOS groups, suggest a beneficial impact of XOS inclusion on gut health. Further research with longer feeding periods and higher XOS levels should be conducted to explore potential positive effects on both growth and gut health parameters.

Interactive effects of a stimbiotic supplementation and wheat bran inclusion in corn- or wheat-based diets on growth performance, ileal digestibility, and expression of nutrient transporters of broilers chickens

A 42-day experiment was conducted to investigate the interactive effects of a stimbiotic (STB) and wheat bran (WB) in broiler chickens receiving diets (DT) based on corn or wheat. A total of 960 Cobb 500 male broiler chicks at zero-day old were allocated to 64 pens with 8 treatments, 8 replicates per treatment, and 15 birds per replicate. The treatments were arranged in a randomized complete block design with 2 × 2 × 2 factorial, with the factors as diet (corn-soybean meal or wheat-soybean meal), STB (with or without), and WB (0 or 50 g/kg). Body weight gain (BWG), feed intake (FI), and mortality-corrected FCR data were collected for the starter (d 0-10), grower (d 10-28), and finisher (d 28-42) phases. Ileal digesta and jejunal tissue were collected on d 18 and 42. Data were analyzed as a 2 × 2 × 2 factorial using a mixed model of JMP. There was no significant 3-way interaction for growth performance and expression of nutrient transporters. There was a significant SB × WB for FCR (P < 0.05) in the grower phase. Stimbiotic supplementation and WB inclusion individually improved (P < 0.05) FCR regardless of cereal type, but this effect was not observed when the two were combined. In the overall phase (d 0-42), birds receiving corn-based diets had higher (P < 0.05) FI and BWG than those receiving wheat-based diets. There was a significant 3-way interaction for ileal digestible energy (IDE) (P < 0.05) and N digestibility (ND) on d 18 and 42 (P < 0.05). There was no effect of STB or WB in corn-based diets, whereas WB inclusion decreased IDE in wheat-based diets, but STB supplementation increased IDE with or without WB. In corn-based diets, WB inclusion increased ND, whereas ND was decreased in wheat-based diets. Supplementation with STB had no effect on ND, but STB increased ND in wheat-based diets with and without WB. Ileal DE was greater (P < 0.05) for wheat- than corn-based diets on d 42. Wheat bran inclusion increased ND in corn-based diets whereas, with STB supplementation, there was no difference in ND with or without WB. There was no difference in ND with or without STB or WB in wheat-based diets. There was a significant STB × DT on the expression of GLUT-1 (P < 0.05). In corn-based diets, STB produced an upward expression of GLUT-1, whereas in wheat-based diets, STB supplementation had no effect. On d 42, stimbiotic supplementation produced upward (P < 0.05) expression of SGLT-1. In conclusion, STB supplementation in wheat- or corn-based diets and with WB inclusion improved energy digestibility. On the other hand, WB inclusion in wheat-based diets decreased nutrient digestibility especially on d 18, thus making room for a positive response to STB supplementation in wheat-based diets compared to the marginal response to STB supplementation observed in corn-based diets.

In vivo analysis the effect of antibiotic growth promoters (AGPs), Oxytetracycline di-hydrate and Tylosin phosphate on the intestinal microflora in broiler chicken

Abstract The study was aimed to analyse the effects of antibiotic growth promoters (AGPs), Oxytetracycline di-hydrate and Tylosin phosphate on the intestinal microflora in broiler chicken. The AGPs were provided in different concentrations solely or in combinations for 42 days of rearing. Faecal samples were collected from the intestine (duodenum, jejunum and caeca) of broiler chicken on 14th, 28th and 42nd days of trial. Samples were cultured on different selective medium and bacterial identification was performed by different biochemical and molecular diagnostic tools. Results showed a significant effect of AGPs on the growth of pathogenic microorganisms such as Escherichia coli and Clostridium perfringens in the intestine. Interestingly, an impaired growth was observed for both bacterium showing a significant effect (P<0.05) of AGPs on E. coli and C. perfringens on day 14th, 28th, and 42nd. This effect was observed solely and in combination while using AGPs. Data further showed that the effect was more prominent in combination and with an increase concentration of AGPs. Remarkably, no impairment was seen on the growth of L. reuteri at different sites of intestine and duration (14th, 28th, and 42nd days). The results showed that the use of AGPs in diet has no harmful effect on beneficial bacteria, however, an impaired growth was seen on the harmful bacteria. It is suggested that a combination of AGPs (OXY-1.0+TP-0.5) is economical and have no harmful effect on the broiler chicken. The use of AGPs in a recommended dose and for a specific period of time are safe to use in poultry both as growth promoter and for the prevention of diseases.

Interactions between the helminth and intestinal microbiome in smallholder chicken farming systems

Helminth parasite infections are widespread in smallholder farming systems affecting farmers and livestock animals. There are pathogenic parasites that populate the gut of their host and coexist closely with the gut microbiota. The physical and immunological environment of the gut can be modified by parasites and microbiota creating a wide range of interactions. These interactions modify the development of infection, affects overall host health, and can modify the way a host interacts with its bacterial microbiota. In addition, where there is a high worm burden parasites will affect the health of the host and intestinal tract colonization. This review highlights key studies on the interaction between helminth parasites and the intestinal microbiome to understand the relationship between parasitic worm infections and gut microbiome health in chickens. Finally, the review discusses modulations, molecular changes, and the importance of helminth-microbiome interactions for the host.

Biophysiology of in ovo administered bioactive substances to improve gastrointestinal tract development, mucosal immunity, and microbiota in broiler chicks

Early embryonic exogenous feeding of bioactive substances is a topic of interest in poultry production, potentially improving gastrointestinal tract (GIT) development, stimulating immunization, and maximizing the protection capability of newly hatched chicks. However, the biophysiological actions and effects of in ovo administered bioactive substances are inconsistent or not fully understood. Thus, this paper summarizes the functional effects of bioactive substances and their interaction merits to augment GIT development, the immune system, and microbial homeostasis in newly hatched chicks. Prebiotics, probiotics, and synbiotics are potential bioactive substances that have been administered in embryonic eggs. Their biological effects are enhanced by a variety of mechanisms, including the production of antimicrobial peptides and antibiotic responses, regulation of T lymphocyte numbers and immune-related genes in either up- or downregulation fashion, and enhancement of macrophage phagocytic capacity. These actions occur directly through the interaction with immune cell receptors, stimulation of endocytosis, and phagocytosis. The underlying mechanisms of bioactive substance activity are multifaceted, enhancing GIT development, and improving both the innate and adaptive immune systems. Thus summarizing these modes of action of prebiotics, probiotics and synbiotics can result in more informed decisions and also provides baseline for further research.

Interactions between enzyme preparations and trace element sources on growth performance and intestinal health of broiler chicks

This experiment was conducted to explore the interactions between enzyme preparations and trace element sources on growth performance and intestinal health of broilers chicks. A total of 480 one-day-old healthy male yellow-feather broilers with similar weight were randomly arranged in a 2  ×  2 factorial design with 2 kinds of compound trace element sources (inorganic [I] and organic [O] trace element supplemented with 80, 8, 60, 40, 0.15 mg/kg of Fe, Cu, Mn, Zn, and Se, respectively) and 2 levels of enzyme preparations (0 and 200 mg/kg). The 4 groups named I, O, IE, and OE with 6 replicates and 20 birds per replicate. The trail lasted for 28 days. Results showed that the average weight (ABW), average daily gain (ADG) of broilers in IE and OE groups significantly increased while the F/G significantly decreased as compared with group I and O (P < 0.05). Enzyme preparation supplementation, regardless of the trace element sources, significantly increased the duodenal and jejunal endogenous enzyme (e.g., Try and AACT) activity, and improved the morphology and jejunal barrier function evidenced by the increased villus height and MUC-2 mRNA expression (P < 0.05). Sequencing data manifested that enzyme preparations favorably modulated the cecal microflora by increasing bacterial diversity and abundance of short-chain fatty acid (SCFA)-producing bacteria (e.g., Anaerostipes, Anaerofusis, and Pygmaioactor), while decreasing the abundance of harmful bacteria (e.g., Desulfovibrio). Factorial analysis indicated that there were no interactions between enzyme preparation and trace element sources on growth performance and intestinal health of broiler chicks. In conclusion, dietary supplementation with enzyme preparations, regardless of the trace element sources, could enhance endogenous enzyme activity, improve intestinal morphology and barrier functions, and favorably modulate the cecal microflora, thereby improving the intestinal health and growth performance of broiler chicks.

A moderate anticoccidial effect of cedrol on Eimeria tenella in broiler chickens

As drug-resistant strains of Eimeria have emerged and concerns about drug residues in poultry have grown, there is renewed interest in identifying natural alternatives to control coccidiosis. Cedrol, a natural sesquiterpene alcohol, was used in this study to test anticoccidial efficacy in chicks. Both the control and treatment groups were orally challenged with 2 × 104 oocysts per chicken. Chicks administered with cedrol had reduced oocyst count, an increase in the relative weight gain rate of chicks, and a decrease in severe swelling of the cecum. Based on the above, ACI was calculated and the cedrol group reached moderate anti-coccidial activity (169.34). In chickens treated with cedrol, there were no changes in serum biochemical parameters, but oxidative stress biomarkers and cytokine levels associated with anticoccidial response were altered. These changes suggest that the administered concentration of cedrol did not have any adverse effects on the chickens while enhancing their antioxidant capacity and immunity, leading to an improved anticoccidial ability. In conclusion, this study shows that the addition of cedrol in poultry production has an anticoccidial effect and successfully improves growth performance during the growth period.

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.

Toward Renewable-Based Prebiotics from Woody Biomass: Potential of Tailored Xylo-Oligosaccharides Obtained by Enzymatic Hydrolysis of Beechwood Xylan as a Prebiotic Feed Supplement for Young Broilers

Although antibiotic resistance emerges naturally, this process has been accelerated by the worldwide overuse and misuse of antibiotics. It is essential to find effective alternatives in the broiler industry to improve poultry health while maintaining production efficiency and product safety. In this study, we aimed to evaluate a potential alternative: wood-derived xylo-oligosaccharides (XOS). The objective of this research was to investigate the potential of XOS prepared using enzymatic hydrolysis of beechwood xylan as a prebiotic feed supplement for broilers. A pilot study was conducted to explore the optimal XOS fraction profile by in vitro fermentation. Subsequently, a semi-continuous enzyme membrane reactor was used, allowing for the production of tailored XOS in large quantities. Given the strong bidirectional relationship between intestinal health, nutrition, and intestinal microbiota composition in broilers, an in vivo experiment was performed to explore the potential of XOS as a prebiotic feed supplement by investigating growth performance, feed conversion ratio, caecal short and medium chain fatty acid (SCFA and MCFA) concentration, and microbiological composition of the caecal content. Results from the pilot study indicated that higher enzyme concentrations in the hydrolysis process yield a product that leads to a higher total SCFA and MCFA- and butyric acid production during in vitro fermentation by caecal bacteria. Supplementation of the tailored XOS to the broiler diet (day 1 (d1)-d8 0.13% wt/wt XOS, d9-d15 0.32% XOS) resulted in higher Bifidobacterium counts, beneficial to the health of birds, on d11 and d15.

Effects of fermented feed on growth performance, serum biochemical indexes, antioxidant capacity, and intestinal health of lion-head goslings

Introduction

The aim of this study was to evaluate the effects of fermented feed on growth performance, antioxidant indexes and intestinal health in lion-head goslings.

Methods

288 male lion-head goslings (one-day-old) were randomly divided into four groups (6 replicates per group, 12 samples per replicate): control group (basal diet) and fermented feed (FF) groups (basal diet supplemented with 2.5, 5.0 and 7.5% FF, respectively). The experimental period lasted 28 days.

Results

The results showed that 5.0 and 7.5% FF groups decreased feed conversion rate (FCR) when compared with the control group (p < 0.05). The 5.0% FF group reduced the activity of alkaline phosphatase (ALP) and lactate dehydrogenase (LDH) in serum; while the 7.5% FF group decreased the concentration of total cholesterol (TC), ALP and LDH activity (p < 0.05). Furthermore, the 7.5% FF group significantly increased total antioxidant capacity (T-AOC) in serum (p < 0.05); 2.5% and 5.0% FF groups significantly increased glutathione peroxidase (GSH-Px) in serum (p < 0.05); all FF groups increased the activity of superoxide dismutase (T-SOD) in serum (p < 0.05). For intestinal health, the villous height and villi/crypt ratio in jejunum were increased in all FF groups, but crypt depth was decreased (p < 0.05); The 5.0% FF groups enhanced T-AOC activity in jejunum (p < 0.05); The 2.5% and 5.0% FF groups enhanced GSH-Px activity (p < 0.05) in jejunum; All FF groups reduced malondialdehyde (MDA) level in jejunum (p < 0.05). LEfSe analysis showed that the cecum microbiota was significantly dominant in the 2.5% FF group compared to the control group including Firmicutes, Lactobacillales, Lactobacillus, and Prevotella; the flora that were significantly dominant in the 5.0% FF group compared to the control group included Bacteroidaceae, Bacteroides, Megamonas, and Prevotella; and the groups that were significantly dominant in the 7.5% FF group compared to the control group included Bacteroidota, Bacteroides, Bacteroidaceae, and Ruminococcaceae.

Discussion

In summary, dietary FF supplementation improved growth performance, serum biochemical parameters and antioxidant capacity of lion-head goslings, as well as improved jejunal tissue morphology and optimized intestinal flora structure. In particular, the FF addition at a dose of 7.5% was relatively more effective for lion- head goslings.

The fermented product of high-yield surfactin strain Bacillus subtilis LYS1 improves the growth performance and intestinal villi morphology in broilers

This study aimed to select Bacillus spp. for surfactin production by solid-state fermentation and to investigate the physiochemical characterizations of the fermented product (FP) and its effect on growth performance, carcass trait, intestinal morphology, and clinical blood biochemistry of broilers. Accordingly, the correlations between the functional components of FP and the growth performance of broilers are elucidated. Four hundred eighty 1-day-old Ross 308 broiler chicks were randomly assigned to dietary supplementation of 2.5% fish meal, 2.5% unfermented product, or 2.5% FP produced by Bacillus subtilis LYS1 (LYS1), Bacillus amyloliquefaciens Da16, B. subtilis Lo6 (Lo6), B. subtilis NSN7, B. subtilis subsp. natto N21, or B. subtilis N12. Each treatment had 6 replicates. The experimental period was 5 wk. Results showed that the Lo6 showed the highest protease activity among all fermented groups. The LYS1 showed the highest surfactin yields (10.69 mg/g) among all fermented groups (P < 0.05). The weight gain (WG), feed conversion ratio (FCR), and production efficiency factor (PEF) of LYS1 group were significantly better than unfermented group at 0 to 3 and 0 to 5-wk-old (P < 0.05). The Bacillus-like counts and surfactin content of FP were moderately correlated to WG (0.7 > r > 0.3), FCR (-0.3 > r > -0.7), and PEF (0.7 > r > 0.3) at 0 to 3 and 0 to 5-wk-old (P < 0.05). The protease activity of FP was moderately correlated to WG (0.7 > r > 0.3), FCR (-0.3 > r > -0.7), and PEF (0.7 > r > 0.3) at 0 to 3-wk-old (P < 0.05). The villus height to crypt depth ratio in duodenum and jejunum of fish meal group and LYS1 group were higher than unfermented group (P < 0.05). In conclusion, LYS1 shows the highest surfactin yields. Diets supplemented with 2.5% LYS1 FP can improve the growth performance and the development of intestinal villi in broilers. Moreover, this study proves that the surfactin content, Bacillus-like counts, and protease activity of FP show a correlation to the growth performance of broilers.

Green Synthesis of ZnO/CuO Nanocomposites Using Parsley Extract for Potential In Vitro Anticoccidial Application

In this study, a simple, low-cost, and environmentally friendly method for the green synthesis of ZnO/CuO nanocomposites (NCs) using parsley extract was developed. The phytochemical components in the parsley leaf extract reacted with precursor salts in solution and yielded ZnO/CuO NCs. The synthesis of the green-synthesized NCs was confirmed via various characterization techniques, including UV-vis spectroscopy, X-ray diffraction (XRD) analysis, energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). Subsequently, the NCs were subjected to rigorous in vitro evaluation of their anticoccidial properties. The results showed that the NCs had a spherical shape within an average particle size of around 70 nm. The green-synthesized NCs were evaluated for their in vitro anticoccidial activity against Eimeria spp. The findings showed that the NCs exhibited a significant anticoccidial effect, with a maximum inhibition of 55.3 ± 0.32% observed at a concentration of 0.5 mg/mL. The exposure to the NCs resulted in notable alterations in the ultrastructure of the oocysts when compared to the control group. The ZnO/CuO NCs synthesized from the parsley leaf extract showed promising potential against coccidiosis and could be used in biomedical applications. Further investigation using an in vivo model is required to ascertain the efficacy of NCs as anticoccidial agents.

The digestive tract histology and geographical distribution of gastrointestinal microbiota in yellow-feather broilers

Exhaustive understanding of intestinal physiological characteristics is the critical precondition for the improvement of intestinal health and growth performance of yellow-feather broilers (YFB). As a vital part of gastrointestinal tract, the symbiotic, complex, and variable microbiota have a profound effect on the nutrition, immunity, health, and production of broilers. Hence, the development status of proventriculus, jejunum, and cecum, and spatial heterogeneity of bacterial community in crop, proventriculus, gizzard, jejunum, cecum, and rectum of adult YFB were detected in our study. The results revealed that proventriculus, jejunum, and cecum of broilers are well-developed based on morphological observation. The Chao and Shannon indexes in cecum and rectum are notably higher than other sections and their microbiota structure is also distinct from foregut. Firmicutes and Lactobacillus are the predominant phylum and genus in all gastrointestinal sections, respectively. As feature species of crop, Lactobacillus spp. mainly settle in foregut, whereas some Clostridia species (unclassified Lachnospiraceae, Faecalibacterium, Romboutsia and so on) are characteristic and more abundant in cecum and rectum. Interestingly, there are 2 Ruminococcus torques strains positively and negatively correlated with cecum development, respectively. In a whole, our findings reveal the specialized digestive physiology and regional distribution of intestinal microbiota in YFB, which provides a reference for the future study on the improvement of growth performance and intestinal development through microbiota manipulation in yellow-feather broilers.

Supplementation of ginger root extract into broiler chicken diet: effects on growth performance and immunocompetence

Ginger contains bioactive compounds that possess anti-inflammatory and antimicrobial properties. In this study, 432-day-old Ross 708 broiler male chicks were randomly allocated to 6 dietary treatments to investigate the effect of ginger root extract (GRE) on immunocompetence and growth performance to 6 wk of age. Treatment 1 (CON) consisted of chicks fed a corn-soybean meal (SBM), a base diet without GRE. Treatment 2 (MX) chicks were given basal diets containing bacitracin methylene disalicylate (BMD) at 0.055 g/kg. Treatments 3 (GRE-0.375%), 4 (GRE-0.75%), 5 (GRE-1.5%), and 6 (GRE-3%) were fed similar diet to control with GRE supplemented at 0.375%, 0.75%, 1.5%, and 3%, respectively. Moreover, HPLC analysis of GRE was carried out to determine the concentration of bioactive compounds found in GRE. Each treatment consisted of 6 replicate pens with 12 chicks/pen. Bodyweight (BW) and feed conversion ratio (FCR) were recorded. Results show that the concentration of bioactive compounds increased with increasing GRE supplementation. Likewise, dietary GRE supplementation did not have any detrimental effect on growth performance parameters up to 1.5%, as values for BWG was not different from CON and MX; however, 3% GRE had the poorest FCR and a lower BWG as compared to other treatments. On d 27 and d 41, fecal and cecal concentrations of total bacteria count (TBC), Escherichia coli, Lactobacillus spp., and Bifidobacterium spp enumerated using selective plating media showed that GRE supplementation significantly reduced (P < 0.05) the amount of TBC and E. coli but increased the number of beneficial microorganisms such as Lactobacillus spp. and Bifidobacterium spp. On d 20, no significant differences were observed (P > 0.05) among all treatments for antibody titer against Newcastle disease virus and total IgY antibodies; however, on d 27, GRE-0.75% had the highest value for both immune indicators and was not different from MX. Dietary supplementation of GRE up to 1.5% enhanced the immune system and suppressed E. coli while promoting the growth of healthy bacteria, without any detrimental effect on growth performance.

A metagenomic catalog for exploring the plastizymes landscape covering taxa, genes, and proteins

There are significant environmental and health concerns associated with the current inefficient plastic recycling process. This study presents the first integrated reference catalog of plastic-contaminated environments obtained using an insilico workflow that could play a significant role in discovering new plastizymes. Here, we combined 66 whole metagenomic data from plastic-contaminated environment samples from four previously collected metagenome data with our new sample. In this study, an integrated plastic-contaminated environment gene, protein, taxa, and plastic degrading enzyme catalog (PDEC) was constructed. These catalogs contain 53,300,583 non-redundant genes and proteins, 691 metagenome-assembled genomes, and 136,654 plastizymes. Based on KEGG and eggNOG annotations, 42% of recognized genes lack annotations, indicating their functions remain elusive and warrant further investigation. Additionally, the PDEC catalog highlights hydrolases, peroxidases, and cutinases as the prevailing plastizymes. Ultimately, following multiple validation procedures, our effort focused on pinpointing enzymes that exhibited the highest similarity to the introduced plastizymes in terms of both sequence and three-dimensional structural aspects. This encompassed evaluating the linear composition of constituent units as well as the complex spatial conformation of the molecule. The resulting catalog is expected to improve the resolution of future multi-omics studies, providing new insights into plastic-pollution related research.

Uncovering changes in microbiome profiles across commercial and backyard poultry farming systems

The microbiome profiles of poultry production systems significantly impact bird health, welfare, and the environment. This study investigated the influence of broiler-rearing systems on the microbiome composition of commercial and backyard chicken farms and their environment over time. Understanding these effects is vital for optimizing animal growth, enhancing welfare, and addressing human and environmental health implications. We collected and analyzed various samples from commercial and backyard farms, revealing significant differences in microbial diversity measurements between the two systems. Backyard farms exhibited higher alpha diversity measurements in soil and water samples, while commercial farms showed higher values for litter and feeder samples. The differences in microbial diversity were also reflected in the relative abundance of various microbial taxa. In backyard farms, Proteobacteria levels increased over time, while Firmicutes levels decreased. Campilobacterota, including the major poultry foodborne pathogen Campylobacter, increased over time in commercial farm environments. Furthermore, Bacteroides, associated with improved growth performance in chickens, were more abundant in backyard farms. Conversely, pathogenic Acinetobacter was significantly higher in backyard chicken fecal and feeder swab samples. The presence of Brevibacterium and Brachybacterium, associated with low-performing broiler flocks, was significantly higher in commercial farm samples. The observed differences in microbial composition and diversity suggest that farm management practices and environmental conditions significantly affect poultry health and welfare and have potential implications for human and environmental health. Understanding these relationships can inform targeted interventions to optimize poultry production, improve animal welfare, and mitigate foodborne pathogens and antimicrobial resistance risks. IMPORTANCE The microbiome of poultry production systems has garnered significant attention due to its implications on bird health, welfare, and overall performance. The present study investigates the impact of different broiler-rearing systems, namely, commercial (conventional) and backyard (non-conventional), on the microbiome profiles of chickens and their environment over time. Understanding the influence of these systems on microbiome composition is a critical aspect of the One-Health concept, which emphasizes the interconnectedness of animal, human, and environmental health. Our findings demonstrate that the type of broiler production system significantly affects both the birds and their environment, with distinct microbial communities associated with each system. This study reveals the presence of specific microbial taxa that differ in abundance between commercial and backyard poultry farms, providing valuable insights into the management practices that may alter the microbiome in these settings. Furthermore, the dynamic changes in microbial composition over time observed in our study highlight the complex interplay between the poultry gut microbiome, environmental factors, and production systems. By identifying the key microbial players and their fluctuations in commercial and backyard broiler production systems, this research offers a foundation for developing targeted strategies to optimize bird health and welfare while minimizing the potential risks to human and environmental health. The results contribute to a growing body of knowledge in the field of poultry microbiome research and have the potential to guide future improvements in poultry production practices that promote a sustainable and healthy balance between the birds, their environment, and the microbial communities they host.

Effects of bacteriophage on Salmonella Enteritidis infection in broilers

Bacteriophages (BP) are viruses that can infect bacteria. The present study evaluated the effect of BP on Salmonella infected broilers. A number of 150 day-old broilers were used in a completely randomized design with five treatments that included: (1) basal diet from day 0 to 28; (2) basal diet + 0.3 g/kg of colistin from day 0 to 28; (3) basal diet from day 1 to 13, and basal diet + 0.4 g/kg of colistin from day 14 to 28; (4) basal diet + 1 g/kg of BP from day 0 to 28; (5) basal diet + 1.5 g/kg of BP from day 0 to 28. On day 13, 15 chickens from each treatment were challenged by Salmonella Enteritidis (SE), while fifteen from each treatment were not; instead, they were kept in the same cage with the challenged chickens (exposed chickens). At 7 and 14 days post-challenge, the number of SE and coliform bacteria in the cecum and liver of colistin and BP-fed birds was lower than the control treatment. In exposed and challenged chickens, the height and surface area of villus were greater in the BP and colistin-supplemented groups. Serum concentrations of aspartate aminotransferase and alanine transaminase were greater, while serum albumin and triglycerides concentrations were lower in the control treatment. The liver of the challenged chickens had more pathological lesions than exposed birds. BP significantly decreased PPARγ gene expression in exposed chickens. In the challenged and exposed chickens, TLR4 gene expression was lower in BP and colistin-treated birds as compared to the control. In conclusion, adding BP to the diet from the day of age prevents the spread of Salmonella.

Effects of dietary Clostridium butyricum on the growth performance, digestion, and intestinal health of spotted sea bass (Lateolabrax maculatus)

Clostridium butyricum (CB) is known to promote growth, enhance immunity, promote digestion, and improve intestinal health. In this study, we investigated the effects of CB in the feed on growth performance, digestion, and intestinal health of juvenile spotted sea bass. To provide a theoretical basis for the development and application of CB in the feed of spotted sea bass, a total of 450 spotted sea bass with an initial body weight of (9.58 ± 0.05) g were randomly divided into six groups. Gradient levels with 0, 0.1%, 0.2%, 0.3%, 0.4%, and 0.5% of CB (1×10⁹ cfu/g) were supplemented into diets, designated as CC, CB1, CB2, CB3, CB4, and CB5, respectively. Each group was fed for 54 days. Our results suggest that dietary 0.2% and 0.3% of CB can significantly increase the weight gain (WG) and specific growth rate (SGR) of spotted sea bass. The addition of CB significantly increased intestinal amylase activity, intestinal villus length, intestinal villus width, and intestinal muscle thickness. Similarly, CB supplementation increased the expression of tumor necrosis factor-α (TNF-α) and interleukin-8 (IL-8). Sequence analysis of the bacterial 16S rDNA region showed that dietary CB altered the intestinal microbiota profile of juvenile spotted sea bass, increasing the dominant bacteria in the intestine and decreasing the harmful bacteria. Overall, dietary addition of CB can improve growth performance, enhance intestinal immunity, improve intestinal flora structure, and comprehensively improve the health of spotted sea bass.

Characterization of potential probiotics Lactobacillus species isolated from the gastrointestinal tract of Rhode Island Red (RIR) chicken in Ethiopia

Background and aims

Nowadays, probiotic microorganisms are given high attention due to their potential for the improvement of animal production and productivity. The natural gut microflora of poultry can serve as an excellent source of optimum probiotic strains. Therefore, this study isolated, identified and characterized potential probiotic Lactobacillus strains from the digestive tract content of RIR chicken in Ethiopia.

Methods

A total of five RIR chickens were randomly taken and a sample was taken from each gastrointestinal content for further analysis. For further characterization, among 190 isolates only 10 representative isolates were randomly taken for further in vitro probiotic potential characterization. The selected isolates were screened and identified based on the biochemical, morphological, and 16S rRNA gene sequences.

Results

Survival isolates of IS3, IS4, IS6, and IS7 were significantly different (P < 0.05) at pH 2. IS3, IS4, IS6, and IS7 showed tolerance for 0.3% bile salt. Isolates of IS1, IS2, IS5, IS7, and IS8 were ampicillin-resistant, and chloramphenicol, ciprofloxacin, and erythromycin were used as antibiotics. All ten isolates showed antagonistic activity against Escherichia coli, Staphylococcus aureus, Salmonella typhimurium, Staphylococcus intermedius, and Salmonella enteritidis. The optimum temperature for all isolates was 45 °C, and all the isolates could grow at 0.69 mol/L of NaCl. Using phylogenetic analysis of the 16SrRNA gene sequence; IS3 was identified as Lactobacillus salivarius, while IS4, IS6, and IS7 were identified as Lactobacillus reuteri.

Conclusions

The results indicated that the selected Lactobacillus isolates can survive the stress conditions of the gastrointestinal tract and can thus be considered potential probiotic candidates for chickens.

Host genotype affects endotoxin release in excreta of broilers at slaughter age

Host genotype, early post-hatch feeding, and pre- and probiotics are factors known to modulate the gut microbiome. However, there is a knowledge gap on the effect of both chicken genotype and these dietary strategies and their interplay on fecal microbiome composition and diversity, which, in turn, can affect the release of endotoxins in the excreta of broilers. Endotoxins are a major concern as they can be harmful to both animal and human health. The main goal of the current study was to investigate whether it was possible to modulate the fecal microbiome, thereby reducing endotoxin concentrations in the excreta of broiler chickens. An experiment was carried out with a 2 × 2 × 2 factorial arrangement including the following three factors: 1) genetic strain (fast-growing Ross 308 vs. slower growing Hubbard JA757); 2) no vs. combined use of probiotics and prebiotics in the diet and drinking water; and 3) early feeding at the hatchery vs. non-early feeding. A total of 624 Ross 308 and 624 Hubbard JA757 day-old male broiler chickens were included until d 37 and d 51 of age, respectively. Broilers (N = 26 chicks/pen) were housed in a total of 48 pens, and there were six replicate pens/treatment groups. Pooled cloacal swabs (N = 10 chickens/pen) for microbiome and endotoxin analyses were collected at a target body weight (BW) of 200 g, 1 kg, and 2.5 kg. Endotoxin concentration significantly increased with age (p = 0.01). At a target BW of 2.5 kg, Ross 308 chickens produced a considerably higher amount of endotoxins (Δ = 552.5 EU/mL) than the Hubbard JA757 chickens (p < 0.01). A significant difference in the Shannon index was observed for the interaction between the use of prebiotics and probiotics, and host genotype (p = 0.02), where Ross 308 chickens with pre-/probiotics had lower diversity than Hubbard JA757 chickens with pre-/probiotics. Early feeding did not affect both the fecal microbiome and endotoxin release. Overall, the results suggest that the chicken genetic strain may be an important factor to take into account regarding fecal endotoxin release, although this needs to be further investigated under commercial conditions.

Effects of Salmonella Enteritidis infection on TLRs gene expression and microbial diversity in cecum of laying hens

Salmonella Enteritidis (SE) is an important foodborne pathogen primarily causing human disease through contaminated food and water. In the current study, to assess the effect of Salmonella Enteritidis infection on the immune system and the microbial diversity of cecum and oviduct in chickens, twelve 24-week-old SE-negative White Leghorn layers were randomly selected and divided into 2 groups. Chickens in the challenge group were orally inoculated with SE, and chickens in the control group received an equal amount of sterilized Phosphate Buffered Saline solution. Serum and tissue samples (cecum, oviduct, ovary, liver, spleen, and pancreas) were collected at 7 days and 14 days post-infection (dpi). Quantitative PCR was used to detect the expression of Toll-like receptors (TLRs) in the cecum, oviduct and ovary. To understand the influence of SE infection on the microbial profile of the cecum and oviduct, microbial community composition of the cecal contents and oviducal contents were analyzed through 16S rRNA sequencing. Results showed that SE infection caused damage to the digestive organs, reproductive organs, and immune organs in laying hens. The expression of TLR1a, TLR1b, TLR2, TLR4, TLR5, TLR7 and TLR15 in the cecum were induced, and the content of IFN-γ, TNF-α, IL-2 and IL-18 in serum increased after SE infection. The composition of the microbial community significantly changed in cecal content, the dominant phylum of Firmicutes increased, and Bacteroidetes decreased significantly. In the oviduct, the microbial diversity became complicated, the dominant bacteria Faecalibacterium was significantly increased, and Bacteroides was significantly decreased. This study investigated the effects of SE infection in laying hens, including host innate immunity, the expression of TLRs, and changes in the composition of microbes in the cecum and reproductive tract. Our results may provide a scientific basis for the Salmonella Enteritidis control in chicken, the maintenance of oviduct function, and the guarantee of clean egg production.

Investigating the modulatory effects of Moringa oleifera on the gut microbiota of chicken model through metagenomic approach

Introduction

This study aimed to assess the effects of supplementing chicken feed with Moringa oleifera leaf powder, a phytobiotic, on the gastrointestinal microbiota. The objective was to examine the microbial changes induced by the supplementation.

Methods

A total of 40, one-day-old chickens were fed their basal diet for 42 days and then divided into two groups: SG1 (basal diet) and SG2 (basal diet + 10 g/kg Moringa oleifera leaf powder). Metagenomics analysis was conducted to analyze operational taxonomic units (OTUs), species annotation, and biodiversity. Additionally, 16S rRNA sequencing was performed for molecular characterization of isolated gut bacteria, identified as Enterococcus faecium. The isolated bacteria were tested for essential metabolites, demonstrating antibacterial, antioxidant, and anticancer activities.

Results and discussion

The analysis revealed variations in the microbial composition between the control group (SG1) and the M. oleifera-treated group (SG2). SG2 showed a 47% increase in Bacteroides and a 30% decrease in Firmicutes, Proteobacteria, Actinobacteria, and Tenericutes compared to SG1. TM7 bacteria were observed exclusively in the M. oleifera-treated group. These findings suggest that Moringa oleifera leaf powder acts as a modulator that enhances chicken gut microbiota, promoting the colonization of beneficial bacteria. PICRUSt analysis supported these findings, showing increased carbohydrate and lipid metabolism in the M.oleifera-treated gut microbiota.

Conclusion

This study indicates that supplementing chicken feed with Moringa oleifera leaf powder as a phytobiotic enhances the gut microbiota in chicken models, potentially improving overall health. The observed changes in bacterial composition, increased presence of Bacteroides, and exclusive presence of TM7 bacteria suggest a positive modulation of microbial balance. The essential metabolites from isolated Enterococcus faecium bacteria further support the potential benefits of Moringa oleifera supplementation.

Plant-Derived Quorum Sensing Inhibitors (Quercetin, Vanillin and Umbelliferon) Modulate Cecal Microbiome, Reduces Inflammation and Affect Production Efficiency in Broiler Chickens

Quorum sensing inhibitors (QSIs) are an attractive alternative to antibiotic growth promoters in farmed animal nutrition. The goal of the study was the diet supplementation of Arbor Acres chickens with quercetin (QC), vanillin (VN), and umbelliferon (UF), which are plant-derived QSIs preliminarily showing cumulative bioactivity. Chick cecal microbiomes were analyzed by 16s rRNA sequencing, inflammation status was assessed by blood sample analyses, and zootechnical data were summarized in the European Production Efficiency Factor (EPEF). When compared to the basal diet control group, a significant increase in the Bacillota:Bacteroidota ratio in the cecal microbiome was found in all experimental subgroups, with the highest expression > 10 at VN + UV supplementation. Bacterial community structure in all experimental subgroups was enriched with Lactobacillaceae genera and also changed in the abundance of some clostridial genera. Indices of richness, alpha diversity, and evenness of the chick microbiomes tended to increase after dietary supplementation. The peripheral blood leukocyte content decreased by 27.9-45.1% in all experimental subgroups, likely due to inflammatory response reduction following beneficial changes in the cecal microbiome. The EPEF calculation showed increased values in VN, QC + UF, and, especially, VN + UF subgroups because of effective feed conversion, low mortality, and broiler weight daily gain.

Association of residual feed intake with intestinal microbiome and metabolome in laying period of ducks

Introduction

Residual feed intake (RFI) is a indicator to evaluate animal feed. This experiment was explored to study the relationship between intestinal microbiome and metabolome of ducks with different residual feed intake during laying period.

Methods

A total of 300 Shaoxing ducks aged 42 weeks were randomly selected and fed a diet of 60 d. At the end of the trial, 20 samples were selected according to the phenotype of RFI and divided into two groups (HRFI and LRFI). The cecal microbiota composition was explored by 16S ribosomal RNA gene sequencing and rectal metabolomics uses liquid chromatography-mass spectrometry (LC-MS) to identify the composition of metabolites in a non-targeted manner.

Results

Results show feed intake and feed conversion ratio in the group HRFI were significantly higher than those in the group LRFI (p < 0.05). Chao1 indices were higher in the group LRFI than in the HRFI (p < 0.05), Shannon and Simpson indices were higher in the group LRFI than in the HRFI (p < 0.01). After linear discriminant analysis effect size (p < 0.05, LDA score > 3), Rikenellaceae, Rikenellaceae_RC9_gut_group, Lactobacillales and Ruminococcus_2, etc. were significantly enriched in the group LRFI at the genus level, while Prevotellaceae_NK3B31_group and Bacteria were significantly enriched in the group HRFI. After LC-MS analysis we found 338 metabolic difference products and 10 metabolic pathways, including the ABC transporter system, cysteine and methionine metabolism, arginine and proline metabolism, and vitamin B6 metabolism, were identified to be associated with the significantly differentially expressed between the groups LRFI and HRFI (p < 0.05). We hypothesize that the difference between ducks with different RFIs is mainly due to the fact that ducks with LRFI have more SCFAs-producing bacteria in their gut microorganisms, which regulate the RFI of animals. This process we found that Phascolarctobaterium and Anaerobiospirillum may provide energy for ABC transporter system by producing SCFAs, and regulate RFI to improve feed utilization efficiency.

Discussion

These results revealed the relationship between microbiome and metabonomics in laying ducks with different RFI, and provided theoretical basis for further study on the relationship between them.

Nutritional Strategies to Improve Meat Quality and Composition in the Challenging Conditions of Broiler Production: A Review

Poultry meat is becoming one of the most important animal protein sources for human beings in terms of health benefits, cost, and production efficiency. Effective genetic selection and nutritional programs have dramatically increased meat yield and broiler production efficiency. However, modern practices in broiler production result in unfavorable meat quality and body composition due to a diverse range of challenging conditions, including bacterial and parasitic infection, heat stress, and the consumption of mycotoxin and oxidized oils. Numerous studies have demonstrated that appropriate nutritional interventions have improved the meat quality and body composition of broiler chickens. Modulating nutritional composition [e.g., energy and crude protein (CP) levels] and amino acids (AA) levels has altered the meat quality and body composition of broiler chickens. The supplementation of bioactive compounds, such as vitamins, probiotics, prebiotics, exogenous enzymes, plant polyphenol compounds, and organic acids, has improved meat quality and changed the body composition of broiler chickens.

Antibiotic Resistance among Gastrointestinal Bacteria in Broilers: A Review Focused on Enterococcus spp. and Escherichia coli

Chickens can acquire bacteria at different stages, and bacterial diversity can occur due to production practices, diet, and environment. The changes in consumer trends have led to increased animal production, and chicken meat is one of the most consumed meats. To ensure high levels of production, antimicrobials have been used in livestock for therapeutic purposes, disease prevention, and growth promotion, contributing to the development of antimicrobial resistance across the resident microbiota. Enterococcus spp. and Escherichia coli are normal inhabitants of the gastrointestinal microbiota of chickens that can develop strains capable of causing a wide range of diseases, i.e., opportunistic pathogens. Enterococcus spp. isolated from broilers have shown resistance to at least seven classes of antibiotics, while E. coli have shown resistance to at least four. Furthermore, some clonal lineages, such as ST16, ST194, and ST195 in Enterococcus spp. and ST117 in E. coli, have been identified in humans and animals. These data suggest that consuming contaminated animal-source food, direct contact with animals, or environmental exposure can lead to the transmission of antimicrobial-resistant bacteria. Therefore, this review focused on Enterococcus spp. and E. coli from the broiler industry to better understand how antibiotic-resistant strains have emerged, which antibiotic-resistant genes are most common, what clonal lineages are shared between broilers and humans, and their impact through a One Health perspective.

Antimicrobial Drug Resistance in Poultry Production: Current Status and Innovative Strategies for Bacterial Control

The world population’s significant increase has promoted a higher consumption of poultry products, which must meet the specified demand while maintaining their quality and safety. It is well known that conventional antimicrobials (antibiotics) have been used in livestock production, including poultry, as a preventive measure against or for the treatment of infectious bacterial diseases. Unfortunately, the use and misuse of these compounds has led to the development and dissemination of antimicrobial drug resistance, which is currently a serious public health concern. Multidrug-resistant bacteria are on the rise, being responsible for serious infections in humans and animals; hence, the goal of this review is to discuss the consequences of antimicrobial drug resistance in poultry production, focusing on the current status of this agroeconomic sector. Novel bacterial control strategies under investigation for application in this industry are also described. These innovative approaches include antimicrobial peptides, bacteriophages, probiotics and nanoparticles. Challenges related to the application of these methods are also discussed.

Lignin from sugarcane bagasse as a prebiotic additive for poultry feed

Diet is a crucial factor on health and well-being of livestock animals. Nutritional strengthening with diet formulations is essential to the livestock industry and animal perfor-mance. Searching for valuable feed additives among by-products may promote not only circular economy, but also functional diets. Lignin from sugarcane bagasse was proposed as a potential prebiotic additive for chickens and incorporated at 1 % (w/w) in commercial chicken feed, tested in two feed forms, namely, mash and pellets. Physico-chemical characterization of both feed types with and without lignin was performed. Also, the prebiotic potential for feeds with lignin was assessed by in vitro gastrointestinal model and evaluated the impact on chicken cecal Lactobacillus and Bifidobacterium. As for the pellet's physical quality, there was a higher cohesion of the pellets with lignin, indicating a higher resistance to breakout and lignin decreases the tendency of the pellets for microbial contamination. Regarding the prebiotic potential, mash feed with lignin showed higher promotion of Bifidobacterium in comparison with mash feed without lignin and to pellet feed with lignin. Lignin from sugarcane bagasse has prebiotic potential as additive to chicken feed when supplemented in mash feed diets, presenting itself as a sustainable and eco-friendly alternative to chicken feed additives supplementation.