Poultry Breeding Industry Research Articles

Expression profile of Toll-like receptors and cytokines in the cecal tonsil of chickens challenged with Eimeria tenella.

Chicken coccidiosis, caused by Eimeria spp., seriously affects the development of the poultry breeding industry. Currently, extensive studies of chicken coccidiosis are mostly focused on acquired immune responses, while information about the innate immune response of chicken coccidiosis is lacking. Toll-like receptor (TLR), the key molecule of the innate immune response, connects innate and adaptive immune responses and induces an immune response against various pathogen infections. Therefore, the quantitative real-time PCR was used to characterize the expression profile of chicken TLRs (chTLRs) and associated cytokines in the cecal tonsil of chickens infected with Eimeria tenella. The results showed that the expression of chTLR1a, chTLR2a, and chTLR5 was significantly upregulated at 3h post-infection, while chTLR1b, chTLR2b, chTLR3, chTLR7, chTLR15 and chTLR21 was significantly downregulated (p < 0.05). In addition, chTLR1a expression rapidly reached the peaked expression at 3h post-infection, while chTLR2b and chTLR15 peaked at 168h post-infection, and chTLR2a expression was highest among chTLRs, peaking at 48h post-infection (p < 0.05). For cytokines, interleukin (IL)-6 and tumor necrosis factor (TNF)-α peaked at 96h post-infection, IL-4 and IL-12 peaked at 144h post-infection, and interferon-γ expression was highest among cytokines at 120h post-infection. In addition, IL-12 and IL-17 were markedly upregulated at 6h post-infection (p < 0.05). These results provide insight into innate immune molecules during E. tenella infection in chickens and suggest that innate immune responses may mediate resistance to chicken coccidiosis.

Alleviating heavy metal accumulation and pathogens’ abundance through processing proper ratio of duck feces and food waste by Black solider fly larvae

ABSTRACT The efficient and sustainable utilization of duck feces is critically essential in China, given its expansive livestock and poultry breeding industry. While the use of black solider fly (BSF) larvae for composting duck feces has gained recognition, public apprehensions concerning the nutritional value and safety of the resultant by-products remain prevalent. This study presents the inaugural assessment of potential risks and quality of resource-based products derived from various proportions of food waste and duck feces processed by BSF larvae. Our findings indicate that mixed substrate A2 yielded BSF larvae with the highest level of N and P, alongside the lowest accumulation of As, Pb and Cd, as well as reduced total pathogen abundance in the remaining substrate when compared to other mixed substrates (A3 and A4). This suggests that an appropriate nutrient composition ratio in the substrates not only facilitated effective conversion but also diminished heavy metal accumulation by BSF larvae. Additionally, a significant negative correlation was observed between N, P, and Cd (R 2 = −0.989, −0.996, p < 0.01), implying that elevated N and P concentrations in BSF larvae may enhance immune function and while further mitigating heavy metal enrichment. Overall, achieving a suitable nutrient ratio of duck feces and food waste is imperative for their scientific and safe utilization, providing valuable insights for the bioconversion of organic solid waste through BSF larvae.

Microcin C7 as a Potential Antibacterial-Immunomodulatory Agent in the Postantibiotic Era: Overview of Its Bioactivity Aspects and Applications.

In the postantibiotic era, the pathogenicity and resistance of pathogens have increased, leading to an increase in intestinal inflammatory disease. Bacterial infections remain the leading cause of animal mortality. With increasing resistance to antibiotics, there has been a significant decrease in resistance to both inflammation and disease in animals, thus decreasing production efficiency and increasing production costs. These side effects have serious consequences and have detracted from the development of China's pig industry. Microcin C7 (McC7) demonstrates potent antibacterial activity against a broad spectrum of pathogens, stable physicochemical properties, and low toxicity, reducing the likelihood of resistance development. Thus, McC7 has received increasing attention as a potential clinical antibacterial and immunomodulatory agent. McC7 has the potential to serve as a new generation of antibiotic substitutes; however, its commercial applications in the livestock and poultry industry have been limited. In this review, we summarize and discuss the biosynthesis, biochemical properties, structural characteristics, mechanism of action, and immune strategies of McC7. We also describe the ability of McC7 to improve intestinal health. Our aim in this study was to provide a theoretical basis for the application of McC7 as a new feed additive or new veterinary drug in the livestock and poultry breeding industry, thus providing a new strategy for alleviating resistance through feed and mitigating drug resistance. Furthermore, this review provides insight into the new functions and anti-infection mechanisms of bacteriocin peptides and proposes crucial ideas for the research, product development, and application of bacteriocin peptides in different fields, such as the food and medical industries.

Rapid and sensitive visual detection of avian leukosis virus by reverse transcription loop-mediated isothermal amplification combined with a lateral flow immunochromatographic strip assay.

Considering that avian leukosis virus (ALV) infection has inflicted massive economic losses on the poultry breeding industry in most countries, its early diagnosis remains an important measure for timely treatment and control of the disease, for which a rapid and sensitive point-of-care test is required. We established a user-friendly, economical, and rapid visualization method for ALV amplification products based on reverse transcription loop-mediated isothermal amplification (RT-LAMP) combined with an immunochromatographic strip in a lateral flow device (LFD). Using the ALVp27 gene as the target, five RT-LAMP primers and one fluorescein-isothiocyanate-labeled probe were designed. After 60 min of RT-LAMP amplification at 64 °C, the products could be visualized directly using the LFD. The detection limit of this assay for ALV detection was 102 RNA copies/μL, and the sensitivity was 100 times that of reverse transcription polymerase chain reaction (RT-PCR), showing high specificity and sensitivity. To verify the clinical practicality of this assay for detecting ALV, the gold standard RT-PCR method was used for comparison, and consistent results were obtained with both assays. Thus, the assay described here can be used for rapid detection of ALV in resource-limited environments.

Efficient biodegradation of feathers by a novel and stable metallo-keratinase production strain Stenotrophomonas sp. Yang-5 isolated from swan farming soil

Feather waste produced by livestock and poultry breeding industry is a kind of biomass resource with great application prospect. Current study aims to obtain a feather-degradation bacteria that could efficiently biodegrade feather waste and maintain environmental friendliness. By using the casein agar medium, a novel keratinase production strain Stenotrophomonas sp. Yang-5 was isolated and then identified by subsequent 16S rRNA sequence. Further keratinase production medium was optimized by single factor and orthogonal experiments. Also, crude keratinase was characterized. Consequently, the highest enzyme activity of 161.95 ± 3.65 U/mL was obtained after 48 h of incubation with optimized conditions consisting of reaction temperature 32.5 °C, initial pH 7.5, 0 g/L CaCl2, 50 g/L fructose, and 15 g/L feather. Yang-5 keratinase demonstrated a broad temperature range of 25 °C − 95 °C and optimal catalytic efficiency at pH 9.0. The keratinase had a half-life of more than 120 min at 70° C, indicating satisfactory thermal stability. Furthermore, 0.25 mol/L Mg2+, Mn2+, K+, and Ca2+ could enhance the enzyme activity to some extent and assigned as the metallo-class of keratinase, among of which Mn2+ resulted in the highest improvement by 2-fold activity enhancement. In addition, 5% (v/v) reducing agents including DMSO, DTT and 2-mercaptoethanol all reinforced the enzyme activity by 3–5 folds. To sum up, thermostable alkaline metallo-keratinase from Stenotrophomonas sp. Yang-5 exhibited favorable stability and could serve as a promising candidate for feather waste degradation as well as environmental protection and feed additive industry.

Quantitative phosphoproteomic analysis of chicken DF-1 cells infected with Eimeria tenella, using tandem mass tag (TMT) and parallel reaction monitoring (PRM) mass spectrometry.

Eimeria tenella is an obligate intracellular parasite which causes great harm to the poultry breeding industry. Protein phosphorylation plays a vital role in host cell-E. tenella interactions. However, no comprehensive phosphoproteomic analyses of host cells at various phases of E. tenella infection have been published. In this study, quantitative phosphoproteomic analysis of chicken embryo DF-1 fibroblasts that were uninfected (UI) or infected with E. tenella for 6h (PI6, the early invasion phase) or 36h (PI36, the trophozoite development phase) was conducted. A total of 10,122 phosphopeptides matched to 3,398 host cell phosphoproteins were identified and 13,437 phosphorylation sites were identified. Of these, 491, 1,253, and 275 differentially expressed phosphorylated proteins were identified in the PI6/UI, PI36/UI, and PI36/PI6 comparisons, respectively. KEGG pathway enrichment analysis showed that E. tenella modulated host cell processes through phosphorylation, including focal adhesion, regulation of the actin cytoskeleton, and FoxO signaling to support its early invasion phase, and modulating adherens junctions and the ErbB signaling pathway to favor its trophozoite development. These results enrich the data on the interaction between E. tenella and host cells and facilitate a better understanding of the molecular mechanisms underlying host-parasite relationships.

Current Situation and Treatment Mechanism of Livestock and Poultry Environmental Pollution from the Perspective of Rural Revitalization

The rapid development of the livestock and poultry breeding industry has brought people a richer variety of meat, poultry, egg and milk products, but at the same time it has also caused serious environmental pollution problems, affecting the healthy and sustainable development of animal husbandry. As a kind of agricultural biological resources, manure is often treated in the form of returning the full amount to the field and washing pens because it has been neglected for a long time. Its true value is not reflected and it also causes serious environmental pollution. Therefore, accelerating the comprehensive utilization of animal manure is an important way to improve the level of resource utilization of manure, which has far-reaching significance. This paper analyzes the current situation of domestic livestock and poultry environmental pollution and the specific situation in Anhui Province, and puts forward suggestions for the effective use of manure from the perspectives of the government and enterprises.

Intervention effects of fructooligosaccharide and astragalus polysaccharide, as typical antibiotic alternatives, on antibiotic resistance genes in feces of layer breeding: advantages and defects

Although antibiotic alternatives are widely used in livestock and poultry breeding industry after in-feed antibiotics ban, their intervention effects on antibiotic resistance genes (ARGs) in these food animals’ feces remain poorly understood. Here effects of fructooligosaccharide (FOS) and astragalus polysaccharide (APS), as typical antibiotic alternatives in China, on ARGs in layer feces were estimated by performing metagenomic sequencings and fluorescence quantitative PCR. Fructooligosaccharide significantly reduced sum abundance of ARGs and mobile genetic elements (MGEs) by increasing Lactobacillus clones and reducing Escherichia clones which had relatively higher abundances of ARG subtypes and MGE subtypes in layer feces. However, at least parts of core ARGs and MGEs categories were not reduced by FOS, such as aminoglycosides- and tetracyclines-resistant genes, Tn916, Integrase, and so on. MGEs and microbiome, especially Escherichia genus and Lactobacillus genus, were the key factors affecting ARGs’ sum abundance. MGEs had a higher correlation coefficient with ARGs’ sum abundance than Escherichia genus and Lactobacillus genus. These findings firstly reveal the defects of antibiotic alternatives in controlling bacterial resistance in livestock and poultry breeding after in-feed antibiotics ban, and more strategies are needed to control pollutions and risks of core ARGs and MGEs in food animals’ feces under a special environment.

Construction and Immunogenicity Evaluation of Recombinant Bacillus subtilis Expressing HA1 Protein of H9N2 Avian Influenza Virus.

The H9N2 subtype of the avian influenza virus (AIV) is one of the main subtypes of low pathogenic AIV, and it seriously affects the poultry breeding industry. Currently, vaccination is still one of China's main strategies for controlling H9N2 avian influenza. In this study, we selected MW548848.1 on the current popular main branch h9.4.2.5 as the reference strain, and we optimized the amino acid sequence of HA1 to make it suitable for expression in Bacillus subtilis. The B. subtilis expression vector showed good safety and stress resistance; therefore, this study constructed a recombinant B. subtilis expressing H9N2 HA1 protein and evaluated its immunogenicity in mice. The following results were obtained: the sIgA level of HA1 protein in small intestine fluid and the IgG level of PHT43-HA1/B. subtilis in serum were significantly improved (P < 0.01); PHT43-HA1/B. subtilis can cause a special immune response in mice; and cytokine detection interferon-gamma (IFN-γ) (P < 0.05) and Interleukin 2 (IL-2) (P < 0.01) expressions significantly increased. Additionally, the study found that PHT43-HA1/B. subtilis can alleviate the attack of H9N2 AIV in the spleen, lungs, and small intestine of mice. This study was the first to use an oral recombinant B. subtilis-HA1 vaccine candidate, and it provides theoretical data and technical reference for the creation of a new live vector vaccine against H9N2 AIV.

Probiotics and vitamins modulate the cecal microbiota of laying hens submitted to induced molting.

Induced molting enables laying hens to relax, restore energy and prolong the laying hen cycle, resolving problems such as poor egg quality and minimizing economic losses caused by rising global feeding costs. However, traditional molting methods may disrupt gut microflora and promote potential pathogens infections. This study used a customized additive with a mixture of probiotics and vitamins to induce molting and examine the cecal microbiota post molting. A total of two hundred 377 day-of-ISA Brown laying hens were randomly assigned to four groups: non-molt with basal diet (C), 12-day feeding restriction (FR) in earlier-molting (B), feed again to 27.12% egg production in middle-molting (A) and reach second peak of egg production over 81.36% in post-molting (D). Sequencing 16S rRNA to analyze cecal microbial composition revealed that there is no significant change in bacterial community abundance post-molting. In contrast to group C, the number of potentially harmful bacteria such as E. coli and Enterococcus was not found to increase in groups B, A, or D. This additive keeps cecal microbiota diversity and community richness steady. In cecal contents, hens in group B had lower Lactobacillus, Lachnospiraceae and Prevotellaceae (vsC, A, and D), no significant differences were found between post-molting and the non-molting. Furthermore, cecal microbiota and other chemicals (antibodies, hormones, and enzymes, etc.) strongly affect immunological function and health. Most biochemical indicators are significantly positively correlated with Prevotellaceae, Ruminococcaceae and Subdoligranulum, while negatively with Phascolarctobacterium and Desulfovibrio. In conclusion, the additive of probiotics and vitamins improved the cecal microbiota composition, no increase in the associated pathogenic microbial community due to traditional molting methods, and enhances hepatic lipid metabolism and adaptive immunological function, supporting their application and induced molting technology in the poultry breeding industry.

Optimizing the scale-up production of fermented astragalus and its benefits to the performance and egg quality of laying hens.

Astragalus is a homologous medicine and food that benefits human beings and poultry rearing. Fermented astragalus (FA) is a valuable product obtained by fermentation, but its scale-up production requires optimization and expansion of solid-state fermentation (SSF). In this study, Lactobacillus pentosus Stm was screened as the most suitable LAB strain for fermenting astragalus due to its excellent capacity. After optimization and expansion of SSF, LAB count and lactic acid content reached 206 × 108 cfu/g and 15.0%, respectively. Meanwhile, the content of bioactive compounds in FA was significantly enhanced. Feeding experiments with laying hens indicated that supplementing FA in the diet significantly improved the performance and egg quality, as evidenced by reduced feed-to-egg ratio and egg cholesterol. This was due to the promotion of intestinal health by shifting intestinal microbiota. Therefore, this is a systematical endeavor of producing scaled-up FA with promising potential as a feed additive in the poultry breeding industry.

The Synergy of Chicken Anemia Virus and Gyrovirus Homsa 1 in Chickens.

Chicken anemia virus (CAV) and Gyrovirus homsa 1 (GyH1) are members of the Gyrovirus genus. The two viruses cause similar clinical manifestations in chickens, aplastic anemia and immunosuppression. Our previous investigation displays that CAV and GyH1 often co-infect chickens. However, whether they have synergistic pathogenicity in chickens remains elusive. Here, we established a co-infection model of CAV and GyH1 in specific pathogen-free (SPF) chickens to explore the synergy between CAV and GyH1. We discovered that CAV and GyH1 significantly inhibited weight gain, increased mortality, and hindered erythropoiesis in co-infected chickens. Co-infected chickens exhibited severe immune organ atrophy and lymphocyte exhaustion. The proventriculus and gizzard had severe hemorrhagic necrosis and inflammation. We also discovered that the viral loads and shedding levels were higher and lasted longer in CAV and GyH1 co-infected chickens than in mono-infected chickens. Our results demonstrate that CAV and GyH1 synergistically promote immunosuppression, pathogenicity, and viral replication in co-infected chicken, highlighting the interaction between CAV and GyH1 in the disease process and increasing potential health risk in the poultry breeding industry, and needs further attention.

Bacillus pumilus TS1 alleviates Salmonella Enteritidis-induced intestinal injury in broilers

BackgroundIn the current context of reduced and limited antibiotic use, several pathogens and stressors cause intestinal oxidative stress in poultry, which leads to a reduced feed intake, slow or stagnant growth and development, and even death, resulting in huge economic losses to the poultry breeding industry. Oxidative stress in animals is a non-specific injury for which no targeted drug therapy is available; however, the health of poultry can be improved by adding appropriate feed additives. Bacillus pumilus, as a feed additive, promotes growth and development and reduces intestinal oxidative stress damage in poultry. Heat shock protein 70 (HSP70) senses oxidative damage and repairs unfolded and misfolded proteins; its protective effect has been widely investigated. Mitogen-activated protein kinase/protein kinase C (MAPK/PKC) and hypoxia inducible factor-1 alpha (HIF-1α) are also common proteins associated with inflammatory response induced by several stressors, but there is limited research on these proteins in the context of poultry intestinal Salmonella Enteritidis (SE) infections. In the present study, we isolated a novel strain of Bacillus pumilus with excellent performance from the feces of healthy yaks, named TS1. To investigate the effect of TS1 on SE-induced enteritis in broilers, 120 6-day-old white-feathered broilers were randomly divided into four groups (con, TS1, SE, TS1 + SE). TS1 and TS1 + SE group chickens were fed with 1.4 × 107 colony-forming units per mL of TS1 for 15 days and intraperitoneally injected with SE to establish the oxidative stress model. Then, we investigated whether TS1 protects the intestine of SE-treated broiler chickens using inflammatory cytokine gene expression analysis, stress protein quantification, antioxidant quantification, and histopathological analysis.ResultsThe TS1 + SE group showed lower MDA and higher GSH-Px, SOD, and T-AOC than the SE group. TS1 alleviated the effects of SE on intestinal villus length and crypt depth. Our results suggest that SE exposure increased the expression of inflammatory factors (IL-1β, IL-6, TNF-α, IL-4, and MCP-1), p38 MAPK, and PKCβ and decreased the expression of HSP60, HSP70, and HIF-1α, whereas TS1 alleviated these effects.ConclusionsBacillus pumilus TS1 alleviated oxidative stress damage caused by SE and attenuated the inflammatory response in broilers through MAPK/PKC regulation of HSPs/HIF-1α.

Dietary Epimedium extract supplementation improves intestinal functions and alters gut microbiota in broilers

BackgroundGrowth-promoting antibiotics have been banned by law in the livestock and poultry breeding industry in many countries. Various alternatives to antibiotics have been investigated for using in livestock. Epimedium (EM) is an herb rich in flavonoids that has many beneficial effects on animals. Therefore, this study was planned to explore the potential of EM as a new alternative antibiotic product in animal feed.MethodsA total of 720 1-day-old male broilers (Arbor Acres Plus) were randomly divided into six groups and fed basal diet (normal control; NC), basal diet supplemented with antibiotic (75 mg/kg chlortetracycline; CTC), and basal diet supplemented with 100, 200, 400 or 800 mg/kg EM extract for 6 weeks (EM100, EM200, EM400 and EM800 groups). The growth performance at weeks 3 and 6 was measured. Serum, intestinal tissue and feces were collected to assay for antioxidant indexes, intestinal permeability, lactic acid and short-chain fatty acids (SCFAs) profiles, microbial composition, and expression of intestinal barrier genes.ResultsThe average daily feed intake in CTC group at 1–21 d was significantly higher than that in the NC group, and had no statistical difference with EM groups. Compared with NC group, average daily gain in CTC and EM200 groups increased significantly at 1–21 and 1–42 d. Compared with NC group, EM200 and EM400 groups had significantly decreased levels of lipopolysaccharide and D-lactic acid in serum throughout the study. The concentrations of lactic acid, acetic acid, propionic acid, butyric acid and SCFAs in feces of birds fed 200 mg/kg EM diet were significantly higher than those fed chlortetracycline. The dietary supplementation of chlortetracycline and 200 mg/kg EM significantly increased ileal expression of SOD1, Claudin-1 and ZO-1 genes. Dietary supplemented with 200 mg/kg EM increased the relative abundances of g_NK4A214_group and Lactobacillus in the jejunal, while the relative abundances of Microbacterium, Kitasatospora, Bacteroides in the jejunal and Gallibacterium in the ileum decreased.ConclusionSupplementation with 200 mg/kg EM extract improved the composition of intestinal microbiota by regulating the core bacterial genus Lactobacillus, and increased the concentration of beneficial metabolites lactic acid and SCFAs in the flora, thereby improving the antioxidant capacity and intestinal permeability, enhancing the function of tight junction proteins. These beneficial effects improved the growth performance of broilers.Graphical

Microencapsulated phage composites with increased gastrointestinal stability for the oral treatment of Salmonella colonization in chicken.

Salmonella infection, one of the common epidemics in the livestock and poultry breeding industry, causes great economic losses worldwide. At present, antibiotics are the most commonly used treatment for Salmonella infection, but the widespread use of antibiotics has increased drug resistance to Salmonella. Phage therapy has gradually become an alternative method to control Salmonella infection. However, phage, a specific virus that can infect bacteria, has poor stability and is prone to inactivation during treatment. Microencapsulated phage microspheres can effectively solve this problem. Accordingly, in this study, Salmonella phages were microencapsulated, using the xanthan gum/sodium alginate/CaCl2/chitooligosaccharides method, to improve their gastrointestinal stability. Furthermore, microencapsulated phages were evaluated for in vitro temperature and storage stability and in vivo therapeutic effect. Phage microspheres prepared with 1 g/100 mL xanthan gum, 2 g/100 mL sodium alginate, 2 g/100 mL CaCl2, and 0.6 g/100 mL chitooligosaccharides were regular in shape and stable in the temperature range of 10-30°C. Also, microencapsulated phages showed significantly improved stability in the simulated gastric juice environment than the free phages (p < 0.05). In the simulated intestinal fluid, microencapsulated phages were completely released after 4 h. Moreover, microencapsulated phages showed good storage stability at 4°C. In the in vivo experiments detecting Salmonella colonization in the intestinal tract of chicks, microencapsulated phages showed a better therapeutic effect than the free phages. In conclusion, microencapsulated phages exhibited significantly improved stability, gastric acid resistance, and thereby efficacy than the free phages. Microencapsulated phages can be potentially used as biological control agents against bacterial infections.

Plant-Derived Bioactive Compounds and Potential Health Benefits: Involvement of the Gut Microbiota and Its Metabolic Activity.

The misuse and abuse of antibiotics in livestock and poultry seriously endanger both human health and the continuously healthy development of the livestock and poultry breeding industry. Plant-derived bioactive compounds (curcumin, capsaicin, quercetin, resveratrol, catechin, lignans, etc.) have been widely studied in recent years, due to their extensive pharmacological functions and biological activities, such as anti-inflammatory, antioxidant, antistress, antitumor, antiviral, lowering blood glucose and lipids, and improving insulin sensitivity. Numerous studies have demonstrated that plant-derived bioactive compounds are able to enhance the host's ability to resist or diminish diseases by regulating the abundance of its gut microbiota, achieving great potential as a substitute for antibiotics. Recent developments in both humans and animals have also highlighted the major contribution of gut microbiota to the host's nutrition, metabolism, immunity, and neurological functions. Changes in gut microbiota composition are closely related to the development of obesity and can lead to numerous metabolic diseases. Mounting evidence has also demonstrated that plant-derived bioactive compounds, especially curcumin, can improve intestinal barrier function by regulating intestinal flora. Furthermore, bioactive constituents can be also directly metabolized by intestinal flora and further produce bioactive metabolites by the interaction between the host and intestinal flora. This largely enhances the protective effect of bioactive compounds on the host intestinal and whole body health, indicating that the bidirectional regulation between bioactive compounds and intestinal flora has great application potential in maintaining the host's intestinal health and preventing or treating various diseases. This review mainly summarizes the latest research progress in the bioregulation between gut microbiota and plant-derived bioactive compounds, together with its application potential in humans and animals, so as to provide theoretical support for the application of plant-derived bioactive compounds as new feed additives and potential substitutes for antibiotics in the livestock and poultry breeding industry. Overall, based on this review, it can be concluded that plant-derived bioactive compounds, by modulating gut microbiota, hold great promise toward the healthy development of both humans and animal husbandry.

Effect of splenic transfer factor on the development of intestinal mucosal barrier in laying hens.

The aim of this study was to investigate the effects of different doses of chicken spleen transfer factor (TF) on the structure of intestinal epithelial cells in different age groups. One-day-old White Leghorns laying hens were randomly divided into four groups: three groups were administered TF at different dosages (0.10, 0.25 or 1.00 mL) and a fourth group was set as control (administered saline, 1.00 mL). Using hematoxylin and eosin staining, high-throughput sequencing, microbiota analysis, quantitative polymerase reaction and western blotting. We measured the effects of different doses of TF on the following: intestinal mucosal epithelial tissue morphology, intestinal mucosal epithelial barrier-related gene expression profiles, and intestinal epithelial tight junction gene protein levels. The collected data show that TF can improve the absorption of nutrients by increasing villus height and crypt depth, and regulate intestinal flora disorders. Furthermore, we verified that the expression of the claudin and occludin tight junctions between intestinal epithelial cells was increased with TF. this research is very important for focusing on the structure and gene expression of intestinal tissues. The results provide a scientific rationale for feeding and nutrition programs for green and healthy farming, as well as technical support to improve the production efficiency of the livestock and poultry breeding industry. © 2022 Society of Chemical Industry.

WGCNA Analysis of Important Modules and Hub Genes of Compound Probiotics Regulating Lipid Metabolism in Heat-Stressed Broilers.

Simple SummaryIn recent years, the high frequency of high-temperature weather has dramatically increased the possibility of heat stress. Heat stress can affect broilers’ production performance, fat deposition and meat quality through the cells, tissues and organs. The effect of heat stress on fat deposition and meat quality significantly affects the production efficiency of broilers. Probiotics as feed additives can alleviate the adverse reactions of heat stress. Compound probiotics (Lactobacillus casei, Lactobacillus acidophilus and Bifidobacterium) are all colonized in the gut of broilers and are common probiotic supplements. Weighted gene co-expression analysis technology can closely connect the transcriptome with the lipid metabolism results to find the related genes that act on a specific eigenvalue. The purpose of this study was to study the effects of compound probiotics on production performance, meat quality and lipid metabolism in heat-stressed broilers through weighted gene co-expression analysis to determine the genes and modules related to lipid metabolism and to provide a theoretical basis for the poultry industry to alleviate heat stress.This study aimed to study compound probiotics’ (Lactobacillus casei, Lactobacillus acidophilus and Bifidobacterium) effects on production performance, lipid metabolism and meat quality in heat-stressed broilers. A total of 400 one-day-old AA broilers were randomly divided into four groups, each containing the same five replicates, with 20 broilers in each replicate. The control (21 °C) and experiment 2 were fed a basic corn–soybean meal diet. Experiment 1 (21 °C) and experiment 3 were fed a basic corn–soybean meal diet with 10 g/kg compound probiotics on days 7 and 28, respectively. The ambient temperature of experiment 2 and experiment 3 was increased to 30–32 °C (9:00–17:00) for 28–42 days, while the temperature for the other time was kept at 21 °C. The results showed that, compared with the control, the production performance and the content of high-density lipoprotein cholesterol in experiment 1 and triglyceride (TG) in experiment 2 increased (p < 0.05). Compared with experiment 2, TG decreased and the production performance increased in experiment 3 (p < 0.05). However, there was no significant change in meat quality indicators. Weighted gene co-expression network analysis (WGCNA) was used to analyze the intramuscular fat, abdominal fat and five blood lipid indicators. We found five related modules. Fatty acid biosynthesis, glycerolipid metabolism, and fat digestion and absorption were the pathways for KEGG enrichment. Additionally, NKX2-1, TAS2R40, PTH, CPB1, SLCO1B3, GNB3 and AQP7 may be the hub genes of compound probiotics regulating lipid metabolism in heat-stressed broilers. In conclusion, this study identified the key genes of compound probiotics regulating lipid metabolism and provided a theoretical basis for the poultry breeding industry to alleviate heat stress.

Piceatannol Alleviates Clostridium perfringens Virulence by Inhibiting Perfringolysin O.

Clostridium perfringens (C. perfringens) is an important foodborne pathogen that can cause diseases such as gas gangrene and necrotizing enteritis in a variety of economic animals, seriously affecting public health and the economic benefits and healthy development of the livestock and poultry breeding industry. Perfringolysin O (PFO) is an important virulence factor of C. perfringens and plays critical roles in necrotic enteritis and gas gangrene, rendering it an ideal target for developing new drugs against infections caused by this pathogen. In this study, based on biological activity inhibition assays, oligomerization tests and computational biology assays, we found that the foodborne natural component piceatannol reduced pore-forming activity with an inhibitory ratio of 83.84% in the concentration of 16 µg/mL (IC50 = 7.83 µg/mL) by binding with PFO directly and changing some of its secondary structures, including 3-Helix, A-helix, bend, and in turn, ultimately affecting oligomer formation. Furthermore, we confirmed that piceatannol protected human intestinal epithelial cells from the damage induced by PFO with LDH release reduced by 38.44% at 16 µg/mL, based on a cytotoxicity test. By performing an animal experiment, we found the C. perfringens clones showed an approximate 10-fold reduction in infected mice. These results suggest that piceatannol may be a candidate for anti-C. perfringens drug development.

Florfenicol-Polyarginine Conjugates Exhibit Promising Antibacterial Activity Against Resistant Strains.

Florfenicol was widely used as antibiotic in the livestock and poultry breeding industry, resulting in a serious problem of drug resistance. In order to solve the resistance of florfenicol, this study designed and synthesized a new series of florfenicol-polyarginine conjugates and tested for antimicrobial activities. Drug-sensitive bacteria, gram-negative bacteria Escherichia coli (E. coli) and gram-positive Staphylococcus aureus (S. aureus), were sensitive to several of the compounds tested. These conjugates also showed excellent activity against drug-resistant strains such as methicillin-resistant S. aureus (MRSA) and florfenicol resistant Escherichia coli strains (2017XJ30, 2019XJ20), one of which as E6 had a minimum inhibitory concentration of 12.5 μmol/L. These conjugates did not allow bacteria to develop resistance and also decreased bacterial growth by membrane depolarization and disruption. Additionally, florfenicol succinate (C1) showed certain activity after coupling with arginine. This suggested that conjugating arginine to florfenicol succinate effectively modulated the properties of prodrugs. These new conjugates may provide useful insights for expanding the pool of antibiotics.