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National Science Review Oct 2023Understanding changes in pathogen behavior (e.g. increased virulence, a shift in transmission channel) is critical for the public health management of emerging...
Understanding changes in pathogen behavior (e.g. increased virulence, a shift in transmission channel) is critical for the public health management of emerging infectious diseases. Genome degradation via gene depletion or inactivation is recognized as a pathoadaptive feature of the pathogen evolving with the host. However, little is known about the exact role of genome degradation in affecting pathogenic behavior, and the underlying molecular detail has yet to be examined. Using large-scale global avian-restricted genomes spanning more than a century, we projected the genetic diversity of Pullorum (bvSP) by showing increasingly antimicrobial-resistant ST92 prevalent in Chinese flocks. The phylogenomic analysis identified three lineages in bvSP, with an enhancement of virulence in the two recently emerged lineages (L2/L3), as evidenced in chicken and embryo infection assays. Notably, the ancestor L1 lineage resembles the serovars with higher metabolic flexibilities and more robust environmental tolerance, indicating stepwise evolutionary trajectories towards avian-restricted lineages. Pan-genome analysis pinpointed fimbrial degradation from a virulent lineage. The later engineered -deletion mutant, and all other five fimbrial systems, revealed behavior switching that restricted horizontal fecal-oral transmission but boosted virulence in chicks. By depleting fimbrial appendages, bvSP established persistent replication with less proinflammation in chick macrophages and adopted vertical transovarial transmission, accompanied by ever-increasing intensification in the poultry industry. Together, we uncovered a previously unseen paradigm for remodeling bacterial surface appendages that supplements virulence-enhanced evolution with increased vertical transmission.
PubMed: 37965675
DOI: 10.1093/nsr/nwad228 -
BioMed Research International 2015Myeloid differentiation primary response gene 88 (MYD88), a universal adapter protein, plays an important role in activating the nuclear factor-κB (NF-κB) and...
Myeloid differentiation primary response gene 88 (MYD88), a universal adapter protein, plays an important role in activating the nuclear factor-κB (NF-κB) and regulating the expression of proinflammatory genes like tumor necrosis factor (TNF) and interleukin-1 (IL-1), which were highly involved in Salmonella Pullorum infection. To detect the relationship between polymorphisms of the MyD88 gene and Salmonella Pullorum disease, we screened the coding region (CDS) of the MYD88 gene by DNA pool construction and sequencing based on case-control study. Eight single nucleotide polymorphisms (SNPs) in the sequenced fragment (5 exons), 7 known loci and one novel mutation named G4810372T (SNP8), were found in the fifth exon. In addition, we found 7 nonsynonymous substitutions. The allele frequency of only one SNP, g.4810191C > T (SNP1), was significantly different (P < 0.05) between case and control groups. The genotype frequencies of SNP1 (g.4810191C > T) and SNP3 (g.4810257G > T) were of significant difference between the case and the control groups (P < 0.05). Collectively, SNPs of the MyD88 gene were significantly associated with susceptibility to Salmonella Pullorum infection, which can be used as a disease-resistant marker in chicken. These results provided a theoretical basis for future research on chicken breeding by marker-assisted selection.
Topics: Animals; Case-Control Studies; Chickens; Genetic Predisposition to Disease; Haplotypes; Linkage Disequilibrium; Polymorphism, Single Nucleotide; Salmonella; Salmonella Infections, Animal
PubMed: 26881204
DOI: 10.1155/2015/692973 -
Poultry Science Dec 2019Pullorum disease caused by Salmonella Pullorum is one of the most important infectious diseases in the poultry industry worldwide, which leads to serious economic losses... (Comparative Study)
Comparative Study
Pullorum disease caused by Salmonella Pullorum is one of the most important infectious diseases in the poultry industry worldwide, which leads to serious economic losses in many developing countries because of its high mortality rate in young chicks. The traditional slide agglutination test with low cost, fast reaction, and on-site detection has been widely used in the diagnosis of Pullorum disease. However, in practice, the test performance is with the disadvantages of false positive results and unstable detection results. In this paper, we developed self-made agglutination antigens prepared by local isolates in the poultry farm and compare the detection performance with commercial agglutination antigens (China Institute of Veterinary Drug Control) and Group D Salmonella ELISA kit (BioChek UK Ltd). The results of detecting 200 serum samples indicated that the consistency of commercial agglutination antigen detecting in 2 times was only 79.5%. Using the ELISA kit as the reference method, the commercial agglutination antigen detecting results of the Kappa test were only moderately consistent (0.58 ∼ 0.59). Meanwhile, positive and total coincidence rates of the self-made agglutination antigen test with more reliable repeat could reach 97.4 and 88%, respectively, and the result of Kappa test was highly consistent (0.75). The Receiver Operating Characteristic curve analysis clarified that the area under the receiver-operating-characteristic curve values of self-made and commercial agglutination antigen tests could reach 0.861 and 0.804, respectively. These results were coincident when detecting known positive serum from the infected chickens. It's worth mentioning that the visible positive reaction of self-made agglutination antigen test appeared faster and stronger than commercial antigen test. In conclusion, self-made Salmonella Pullorum agglutination antigen developed in this study was much better than commercial agglutination antigen and is expected to be a valuable tool in the diagnosis of the epidemiology of Salmonella Pullorum.
Topics: Agglutination Tests; Animals; Antigens, Bacterial; Chickens; Enzyme-Linked Immunosorbent Assay; Poultry Diseases; Salmonella; Salmonella Infections, Animal
PubMed: 31399741
DOI: 10.3382/ps/pez453 -
International Journal of Molecular... Feb 2023Pure cultures of chicken intestinal microbial species may still be crucial and imperative to expound on the function of gut microbiota, and also contribute to the...
Pure cultures of chicken intestinal microbial species may still be crucial and imperative to expound on the function of gut microbiota, and also contribute to the development of potential probiotics and novel bioactive metabolites from gut microbiota. In this study, we isolated and identified 507 chicken intestinal bacterial isolates, including 89 previously uncultured isolates. Among these, a total of 63 strains, belonging to , , , , , and , exhibited antibacterial activity against . Acid tolerance tests showed strain YPG14 ( strain YPG14) has a particularly strong tolerance to acid. We further characterized other probiotic properties of strain YPG14. In simulated intestinal fluid, the growth of strain YPG14 remained stable after incubation for 4 h. The auto-aggregation test showed the auto-aggregation percentage of strain YPG14 was recorded as 15.0 ± 0.38%, 48.3 ± 2.51%, and 75.1 ± 4.44% at 3, 12, and 24 h, respectively. In addition, the mucin binding assay showed strain YPG14 exhibited 12.07 ± 0.02% adhesion to mucin. Antibiotic sensitivity testing showed that strain YPG14 was sensitive to the majority of the tested antibiotics. The anti- Pullorum (. Pullorum) infection effect in vivo revealed that the consumption of strain YPG14 could significantly improve body weight loss and survival rate of chicks infected by . Pullorum; reduce the loads of . Pullorum in the jejunum, liver, spleen, and feces; and alleviate the jejunum villi morphological structure damage, crypt loss, and inflammatory cell infiltration caused by . Pullorum. Overall, this study may help us to understand the diversity of chicken intestinal microflora and provide some insights for potential probiotic development from gut microbiota and may find application in the poultry industry.
Topics: Animals; Gastrointestinal Microbiome; Chickens; Intestines; Limosilactobacillus reuteri; Anti-Bacterial Agents; Probiotics; Mucins
PubMed: 36769368
DOI: 10.3390/ijms24033045 -
Poultry Science Apr 2022Salmonellosis is a severe problem that threatens the poultry sector worldwide right now. Salmonella gallinarium and Salmonella pullorum (Fowl typhoid) are the most... (Review)
Review
Salmonellosis is a severe problem that threatens the poultry sector worldwide right now. Salmonella gallinarium and Salmonella pullorum (Fowl typhoid) are the most pathogenic serovars in avian species leading to systemic infection resulting in severe economic losses in the poultry industry. Nontyphoidal serotypes of Salmonella (Paratyphoid disease) constitute a public health hazard for their involvement in food poisoning problems in addition to their zoonotic importance. Also, Salmonella species distribution is particularly extensive. They resisted environmental conditions that made it difficult to control their spread for a long time. Therefore, the current review aimed to through light on Salmonellosis in poultry with particular references to its pathogenesis, economic importance, immune response to Salmonella, Salmonella antibiotics resistance, possible methods for prevention and control of such problems using promising antibiotics alternatives including probiotics, prebiotics, symbiotics, organic acids, essential oils, cinnamaldehyde, chitosan, nanoparticles, and vaccines.
Topics: Animals; Anti-Bacterial Agents; Chickens; Poultry; Poultry Diseases; Salmonella Food Poisoning; Salmonella Infections, Animal
PubMed: 35176704
DOI: 10.1016/j.psj.2022.101716 -
Poultry Science Mar 2019To reveal differences in virulence among strains of Salmonella enterica serovar Pullorum (S. Pullorum), we used 2 cell-based infection models and a chicken embryo... (Comparative Study)
Comparative Study
To reveal differences in virulence among strains of Salmonella enterica serovar Pullorum (S. Pullorum), we used 2 cell-based infection models and a chicken embryo infection model in this study. S. Pullorum strain S06004 was used to infect 4 different avian cell lines (HD-11, DF-1, LMH, DT-40), and the results showed that the infection of S06004 in both LMH and HD-11 cells was more stable than in DF-1 and DT-40 cells. Therefore, the HD-11 and LMH cell lines were used as the appropriate macrophage and epithelial cell models, respectively, to study the infection of S. Pullorum. Fifty strains isolated during the years 1962 to 2010 were then analyzed to compare their infection rates in HD-11 and LMH cells. The result showed that the infection rates of most strains were very similar to that of S06004, except for S9876 which displayed the highest infection rate among these strains. Based on the cell infection results, 10 strains were selected to be used in the chicken embryo infection model. Sixteen-day-old SPF chicken embryos were infected with the pathogen at a dose of 103 CFU/100 μL via allantoic cavity inoculation. The strains C79-13, 7101, and S06013 caused death of more than 80% embryos, whereas S09C12 and 6703 resulted less than 20% death. Thus, this study established cell-based infection models to screen S. Pullorum strains in vitro, and a chick embryo model to evaluate their in vivo virulence.
Topics: Animals; Cell Line; Cell Line, Tumor; Chick Embryo; Chickens; Epithelial Cells; Macrophages; Poultry Diseases; Salmonella Infections, Animal; Salmonella enterica; Serogroup; Virulence
PubMed: 30325454
DOI: 10.3382/ps/pey482 -
PloS One 2021Salmonella enterica serovar Gallinarum biovar Pullorum (bvP) and biovar Gallinarum (bvG) are the etiological agents of pullorum disease (PD) and fowl typhoid (FT)... (Comparative Study)
Comparative Study
Salmonella enterica serovar Gallinarum biovar Pullorum (bvP) and biovar Gallinarum (bvG) are the etiological agents of pullorum disease (PD) and fowl typhoid (FT) respectively, which cause huge economic losses to poultry industry especially in developing countries including India. Vaccination and biosecurity measures are currently being employed to control and reduce the S. Gallinarum infections. High endemicity, poor implementation of hygiene and lack of effective vaccines pose challenges in prevention and control of disease in intensively maintained poultry flocks. Comparative genome analysis unravels similarities and dissimilarities thus facilitating identification of genomic features that aids in pathogenesis, niche adaptation and in tracing of evolutionary history. The present investigation was carried out to assess the genotypic differences amongst S.enterica serovar Gallinarum strains including Indian strain S. Gallinarum Sal40 VTCCBAA614. The comparative genome analysis revealed an open pan-genome consisting of 5091 coding sequence (CDS) with 3270 CDS belonging to core-genome, 1254 CDS to dispensable genome and strain specific genes i.e. singletons ranging from 3 to 102 amongst the analyzed strains. Moreover, the investigated strains exhibited diversity in genomic features such as virulence factors, genomic islands, prophage regions, toxin-antitoxin cassettes, and acquired antimicrobial resistance genes. Core genome identified in the study can give important leads in the direction of design of rapid and reliable diagnostics, and vaccine design for effective infection control as well as eradication. Additionally, the identified genetic differences among the S. enterica serovar Gallinarum strains could be used for bacterial typing, structure based inhibitor development by future experimental investigations on the data generated.
Topics: Animals; Bacterial Proteins; Chickens; Genomics; India; Poultry Diseases; Salmonella Infections, Animal; Salmonella enterica; Serogroup
PubMed: 34411120
DOI: 10.1371/journal.pone.0255612 -
The Indian Journal of Medical Research Jul 2019Salmonellosis due to the consumption of contaminated poultry products is a well-known public health concern, and assessing the distribution of Salmonella serovars among...
BACKGROUND & OBJECTIVES
Salmonellosis due to the consumption of contaminated poultry products is a well-known public health concern, and assessing the distribution of Salmonella serovars among poultry becomes important for better prevention and control. The objective of the present study was to assess the distribution of Salmonella serovars among poultry.
METHODS
The isolates received at National Salmonella and Escherichia Centre during 2011-2016 were subjected to biochemical identification, followed by serological characterization to identify the Salmonella serovars, and the data were presented to exhibit the distribution of Salmonella serovars among poultry.
RESULTS
Salmonella was found to be present in poultry in all the regions included in the study. Salmonella Typhimurium, S. Gallinarum and S. Enteritidis were the most prevalent serovars accounting for 96.2 per cent of isolates. Salmonella was identified in poultry from all major egg-producing and egg-consuming States. Other serovars which were scantly identified included S. Infantis (2.7%), S. Montevideo (0.64%), S. Newport (0.26%) and S. Pullorum (0.13%).
INTERPRETATION & CONCLUSIONS
Diverse distribution of Salmonella serovars in poultry in India, with known potential to infect human population and/or other poultry flocks, requires urgent nationwide stringent control measures.
Topics: Animals; Chickens; Genetic Variation; Humans; India; Poultry; Salmonella enterica; Salmonella typhimurium; Serogroup
PubMed: 31571635
DOI: 10.4103/ijmr.IJMR_1798_17 -
Frontiers in Veterinary Science 2017Antimicrobial resistance (AMR) is a global health threat, and antimicrobial usage and AMR in animal production is one of its contributing sources. Poultry is one of the... (Review)
Review
Antimicrobial resistance (AMR) is a global health threat, and antimicrobial usage and AMR in animal production is one of its contributing sources. Poultry is one of the most widespread types of meat consumed worldwide. Poultry flocks are often raised under intensive conditions using large amounts of antimicrobials to prevent and to treat disease, as well as for growth promotion. Antimicrobial resistant poultry pathogens may result in treatment failure, leading to economic losses, but also be a source of resistant bacteria/genes (including zoonotic bacteria) that may represent a risk to human health. Here we reviewed data on AMR in 12 poultry pathogens, including avian pathogenic (APEC), Pullorum/Gallinarum, (ORT), spp., , and . A number of studies have demonstrated increases in resistance over time for . Pullorum/Gallinarum, , and . Among Enterobacteriaceae, APEC isolates displayed considerably higher levels of AMR compared with . Pullorum/Gallinarum, with prevalence of resistance over >80% for ampicillin, amoxicillin, tetracycline across studies. Among the Gram-negative, non-Enterobacteriaceae pathogens, ORT had the highest levels of phenotypic resistance with median levels of AMR against co-trimoxazole, enrofloxacin, gentamicin, amoxicillin, and ceftiofur all exceeding 50%. In contrast, levels of resistance among isolates were less than 20% for all antimicrobials. The study highlights considerable disparities in methodologies, as well as in criteria for phenotypic antimicrobial susceptibility testing and result interpretation. It is necessary to increase efforts to harmonize testing practices, and to promote free access to data on AMR in order to improve treatment guidelines as well as to monitor the evolution of AMR in poultry bacterial pathogens.
PubMed: 28848739
DOI: 10.3389/fvets.2017.00126 -
Antibiotics (Basel, Switzerland) Sep 2022Extensive studies have shown that potassium diformate (KDF), an antibiotic substitute used as a feed additive, improves animal growth performance, although there is less...
Extensive studies have shown that potassium diformate (KDF), an antibiotic substitute used as a feed additive, improves animal growth performance, although there is less direct evidence of its preventive effect on bacterial infections and its influence on the intestinal flora of animals. In this study, the inhibition effect of KDF on , an important enteric pathogen causing pullorum disease, was investigated in vitro and on a chicken infection model. The effect of KDF on the diversities and structures of chicken duodenal and cecum flora were also investigated using 16S rRNA gene sequencing. The results showed that addition of 0.5% KDF in feed or 0.1% KDF in drinking water significantly reduced the bacterial loads and the degree of pathological changes in the cecum, improved digestion and reduced the pH of the gastrointestinal tract of chickens infected with . KDF also significantly modified the diversity and abundance of intestinal microflorae in chickens. In particular, it promoted the colonization of several probiotics, such as , , and , which are involved in maintenance of the intestinal barrier, modulation of inflammation, energy supply for intestinal cells and pathogen resistance. These results enrich the theoretical basis for the clinical application of KDF in chickens.
PubMed: 36140044
DOI: 10.3390/antibiotics11091265