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Antibiotics (Basel, Switzerland) Dec 2023subsp. serovar Gallinarum (G) has two distinct biovars, Pullorum and Gallinarum. They are bacterial pathogens that exhibit host specificity for poultry and aquatic... (Review)
Review
subsp. serovar Gallinarum (G) has two distinct biovars, Pullorum and Gallinarum. They are bacterial pathogens that exhibit host specificity for poultry and aquatic birds, causing severe systemic diseases known as fowl typhoid (FT) and Pullorum disease (PD), respectively. The virulence mechanisms of biovars Gallinarum and Pullorum are multifactorial, involving a variety of genes and pathways that contribute to their pathogenicity. In addition, these serovars have developed resistance to various antimicrobial agents, leading to the emergence of multidrug-resistant strains. Due to their economic and public health significance, rapid and accurate diagnosis is crucial for effective control and prevention of these diseases. Conventional methods, such as bacterial culture and serological tests, have been used for screening and diagnosis. However, molecular-based methods are becoming increasingly important due to their rapidity, high sensitivity, and specificity, opening new horizons for the development of innovative approaches to control FT and PD. The aim of this review is to highlight the current state of knowledge on biovars Gallinarum and Pullorum, emphasizing the importance of continued research into their pathogenesis, drug resistance and diagnosis to better understand and control these pathogens in poultry farms.
PubMed: 38247582
DOI: 10.3390/antibiotics13010023 -
Iranian Journal of Microbiology Oct 2023Antibiotic resistance is an indicator of the passively acquired and circulating resistance genes. Gallinarum significantly affects the poultry food industry. The...
BACKGROUND AND OBJECTIVES
Antibiotic resistance is an indicator of the passively acquired and circulating resistance genes. Gallinarum significantly affects the poultry food industry. The present study is the first study of the Gallinarum biofilm in Iran, which is focused on the characterization of the Gallinarum serovars and their acquired antibiotic resistance genes circulating in poultry fields in central and northwestern Iran.
MATERIALS AND METHODS
Sixty isolates of . Gallinarum serovar were collected from feces of live poultry. The bacteria were isolated using biochemical tests and confirmed by Multiplex PCR. Biofilm formation ability and the antibacterial resistance were evaluated using both phenotypic and genotypic methods. The data were analyzed using SPSS software.
RESULTS
According to Multiplex PCR for , and genes, all 60 . Gallinarum serovars were Gallinarum biovars. In our study, the antibiotic resistance rate among isolated strains was as follows: Penicillin (100%), nitrofurantoin (80%), nalidixic acid (45%), cefoxitin (35%), neomycin sulfate (30%), chloramphenicol (20%), and ciprofloxacin (5%). All isolates were susceptible to imipenem, ertapenem, ceftriaxone, ceftazidime, and ceftazidime+clavulanic acid. All sixty isolates did not express the resistance genes , , and . On the other hand, they expressed (85%), (75%), (70%), (60%), (20%), (15%), (10%), (5%), and (5%). All Gallinarum isolates formed biofilm and expressed gene.
CONCLUSION
Considering that the presence of this bacteria is equal to the death penalty to the herd, the distribution of resistance genes could be a critical alarm for pathogen monitoring programs in the region. This study showed a positive correlation between biofilm formation and 50% of tested resistance genes. Also, it was found that the most common circulating biovars are multidrug-resistant.
PubMed: 37941876
DOI: 10.18502/ijm.v15i5.13869 -
Microbial Pathogenesis Sep 2023Salmonella enterica serovar Gallinarum causes Fowl Typhoid in poultry, and it is host specific to avian species. The reasons why S. Gallinarum is restricted to avians,...
Salmonella enterica serovar Gallinarum causes Fowl Typhoid in poultry, and it is host specific to avian species. The reasons why S. Gallinarum is restricted to avians, and at the same time predominately cause systemic infections in these hosts, are unknown. In the current study, we developed a surgical approach to study gene expression inside the peritoneal cavity of hens to shed light on this. Strains of the host specific S. Gallinarum, the cattle-adapted S. Dublin and the broad host range serovar, S. Enteritidis, were enclosed in semi-permeable tubes and surgically placed for 4 h in the peritoneal cavity of hens and for control in a minimal medium at 41.2 °C. Global gene-expression under these conditions was compared between serovars using tiled-micro arrays with probes representing the genome of S. Typhimurium, S. Dublin and S. Gallinarum. Among other genes, genes of SPI-13, SPI-14 and the macrophage survival gene mig-14 were specifically up-regulated in the host specific serovar, S. Gallinarum, and further studies into the role of these genes in host specific infection are highly indicated. Analysis of pathways and GO-terms, which were enriched in the host specific S. Gallinarum without being enriched in the two other serovars indicated that host specificity was characterized by a metabolic fine-tuning as well as unique expression of virulence associated pathways. The cattle adapted serovar S. Dublin differed from the two other serovars by a lack of up-regulation of genes encoded in the virulence associated pathogenicity island 2, and this may explain the inability of this serovar to cause disease in poultry.
Topics: Animals; Female; Cattle; Serogroup; Chickens; Transcriptome; Salmonella enterica; Salmonella Infections, Animal; Salmonella enteritidis
PubMed: 37419218
DOI: 10.1016/j.micpath.2023.106236 -
Brazilian Journal of Microbiology :... Sep 2023Salmonella is present in the poultry production chain and is a major challenge in terms of food safety and animal health. The early Salmonella detection is one of the...
Salmonella is present in the poultry production chain and is a major challenge in terms of food safety and animal health. The early Salmonella detection is one of the main tools to control and prevent the transmission of this pathogen. Microbiological isolation and serotyping to identify and differentiate Salmonella serovars are laborious processes, time-consuming, and expensive. Therefore, molecular diagnostic methods can be rapid and efficient alternatives to the detection of this pathogen. Thus, the aim herein was to standardize and evaluate the use of loop-mediated isothermal amplification (LAMP) in comparison with real-time PCR (qPCR) for detection of Salmonella associated with a multiplex qPCR for simultaneous identification and differentiation of S. Enteritidis, S. Typhimurium, S. Pullorum, and S. Gallinarum. The LAMP, qPCR, and multiplex qPCR assays were comparable in specificity. The three techniques were evaluated for specificity for 16 different serovars of Salmonella and for 37 strains of the serovars of interest. The limit of detection and the efficiency of the LAMP, qPCR, and multiplex qPCR reactions were determined. The techniques were applied to 33 samples of chicken carcasses and compared to the results of conventional microbiology for validation. As results, LAMP was specific in the detection of different Salmonella serovars but presented lower limit of detection ranging from 10 to 10 CFU/reaction. In comparison, qPCR could detect less cells (10 to 10 CFU/reaction), reaching equal specificity and better repeatability in the assays. The qPCR multiplexing for identification of the different serovars also showed good specificity, with the detection threshold between entre 10 and 10 CFU/reaction. The results obtained in the analyses on poultry carcasses suggested a correspondence between the results obtained in molecular methods and in conventional microbiology. Thus, the proposed assays are promising for the diagnosis of Salmonella in poultry carcasses, already proved to be faster and more efficient than conventional diagnostics techniques, being of great interest for poultry production, animal, and public health.
Topics: Animals; Poultry; Serogroup; Salmonella; Food Safety; Chickens; Sensitivity and Specificity
PubMed: 37582950
DOI: 10.1007/s42770-023-01095-y -
Poultry Science Jul 2024An effective vaccine strategy is indispensable against infectious bronchitis virus (IBV) and fowl typhoid (FT), both of which threaten the poultry industry. This study...
A low-endotoxic Salmonella enterica Gallinarum serovar delivers infectious bronchitis virus immunogens via a dual-promoter vector system that drives protective immune responses through MHC class-I and -II activation in chickens.
An effective vaccine strategy is indispensable against infectious bronchitis virus (IBV) and fowl typhoid (FT), both of which threaten the poultry industry. This study demonstrates a vector system, pJHL270, designed to express antigens in prokaryotic and eukaryotic cells. The vector system stimulates immune responses via synchronized antigen presentation to MHC class-I and -II molecules to produce balanced Th1/Th2 responses. The vaccine antigens were crafted by selecting the consensus sequence of the N-terminal domain of the spike protein (S1-NTD) and a conserved immunogenic region of the nucleocapsid protein (N-) from IBV strains circulating in South Korea. The vaccine antigen was cloned and transformed into a live-attenuated Salmonella Gallinarum (SG) strain, JOL2854 (∆lon, ∆cpxR, ∆rfaL, ∆pagL, ∆asd). Western blot analysis confirmed concurrent antigen expression in Salmonella and eukaryotic cells. Oral immunization with the SG-based IBV vaccine construct JOL2918 induced IBV antigen and Salmonella-specific humoral and cell-mediated immune responses in chickens. PBMCs collected from immunized chickens revealed that MHC class-I and -II expression had increased 3.3-fold and 2.5-fold, respectively, confirming MHC activation via bilateral antigen expression and presentation. Immunization induced neutralizing antibodies (NAbs) and reduced the viral load by 2-fold and 2.5-fold in the trachea and lungs, respectively. The immunized chickens exhibited multifaceted humoral, mucosal, and cell-mediated responses via parallel MHC class-I and -II activation as proof of a balanced Th1/Th2 immune response. The level of NAbs, viral load, and gross and histological analyses provide clear evidence that the construct provides protection against IBV and FT.
Topics: Animals; Chickens; Infectious bronchitis virus; Poultry Diseases; Coronavirus Infections; Salmonella enterica; Viral Vaccines; Serogroup; Genetic Vectors; Promoter Regions, Genetic; Histocompatibility Antigens Class I
PubMed: 38795516
DOI: 10.1016/j.psj.2024.103844 -
Frontiers in Veterinary Science 2024serovar Gallinarum () is an important host-specific pathogen that causes fowl typhoid, a severe systemic, septicemic, and fatal infection, in chickens. causes high...
serovar Gallinarum () is an important host-specific pathogen that causes fowl typhoid, a severe systemic, septicemic, and fatal infection, in chickens. causes high morbidity and mortality in chickens and poses a significant burden and economic losses to the poultry industry in many developing countries. However, the virulence factors and mechanisms of -induced systemic infection in chickens remain poorly understood. In this study, we constructed a pathogenicity island-14 (SPI-14) mutant strain (mSPI-14) of and evaluated the pathogenicity of mSPI-14 in the chicken systemic infection model. The mSPI-14 exhibited the same level of bacterial growth and morphological characteristics but significantly reduced resistance to bile acids compared with the wild-type (WT) strain . The virulence of mSPI-14 was significantly attenuated in the chicken oral infection model . Chickens infected with WT showed typical clinical symptoms of fowl typhoid, with all birds succumbing to the infection within 6 to 9 days post-inoculation, and substantial increases in bacterial counts and significant pathological changes in the liver and spleen were observed. In contrast, all mSPI-14-infected chickens survived, the bacterial counts in the organs were significantly lower, and no significant pathological changes were observed in the liver and spleen. The expression of interleukin (IL)-1β, IL-12, CXCLi1, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ in the liver of mSPI-14-infected chickens were significantly lower than those in the WT-infected chickens. These results indicate that SPI-14 is a crucial virulence factor in systemic infection of chickens, and avirulent mSPI-14 could be used to develop a new attenuated live vaccine to prevent infection in chickens.
PubMed: 38846788
DOI: 10.3389/fvets.2024.1401392 -
Developmental and Comparative Immunology Dec 2023The H9N2 avian influenza virus significantly affects the health of poultry and humans. We identified a prokaryotic and eukaryotic dual-expression vector system, pJHL270,...
Salmonella delivers H9N2 influenza virus antigens via a prokaryotic and eukaryotic dual-expression vector and elicits bivalent protection against avian influenza and fowl typhoid.
The H9N2 avian influenza virus significantly affects the health of poultry and humans. We identified a prokaryotic and eukaryotic dual-expression vector system, pJHL270, that can provide simultaneous MHC class I and II stimulation of the host immune system, and we designed vaccine antigens by selecting the consensus HA1 sequence and M2e antigens from H9N2 virus circulating in South Korea from 2000 to 2021. The genes were cloned into the pJHL270 vector, and the cloned plasmid was delivered by a live-attenuated Salmonella Gallinarum (SG) strain. The immunity and protective efficacy of the SG-based H9N2 vaccine construct, JOL2922, against avian influenza and fowl typhoid (FT) were evaluated. The Ptrc and CMV promoters conferred antigen expression in prokaryotic and eukaryotic cells to induce balanced Th-1/Th-2 immunity. Chickens immunized with JOL2922 yielded high antigen-specific humoral and mucosal immune responses. qRT-PCR revealed that the strain generated polyfunctional IFN-γ and IL-4 secretion in immunized chickens. Furthermore, a FACS analysis showed increased CD3CD4+ and CD3CD8+ T-cell subpopulations following immunization. Peripheral Blood Mononuclear Cells (PBMCs) harvested from the immunized chickens significantly increased MHC class I and II expression, 3.5-fold and 2.5-fold increases, respectively. Serum collected from the immunized groups had an evident hemagglutinin inhibition titer of ≥6 log. Immunization reduced the lung viral titer by 3.8-fold within 5 days post-infection. The strain also generated SG-specific humoral and cellular immune responses. The immunized birds all survived a virulent SG wild-type challenge. In addition, the bacterial burden was reduced by 2.7-fold and 2.1-fold in spleen and liver tissue, respectively, collected from immunized chickens. Our data indicate that an attenuated SG strain successfully delivered the dual-expression vector system and co-stimulated MHC class I and II antigen presentation pathways via exogenous and endogenous antigen presentation, thereby triggering a balanced Th-1/Th-2-based immune response and conferring effective protection against avian influenza and FT.
PubMed: 37714394
DOI: 10.1016/j.dci.2023.105058 -
Poultry Science Aug 2023Significant differences in pathogenicity between Salmonella Enteritidis and Salmonella Gallinarum exist despite the fact that S. Gallinarum is a direct descendant of S....
Significant differences in pathogenicity between Salmonella Enteritidis and Salmonella Gallinarum exist despite the fact that S. Gallinarum is a direct descendant of S. Enteritidis. It was hypothesized that such various properties may be in part the result of differences in structure and functions of type 1 fimbriae (T1Fs). In S. Enteritidis, T1Fs bind to oligomannosidic structures carried by host cell glycoproteins and are called mannose-sensitive T1Fs (MST1F). In S. Gallinarum, T1Fs lost ability to bind such carbohydrate chains, and were named mannose-resistant MRT1Fs (MRT1F). Therefore, the present study was undertaken to evaluate the role of MST1Fs and MRT1Fs in the adhesion, invasion, intracellular survival and cytotoxicity of S. Enteritidis and S. Gallinarum toward chicken intestinal CHIC8-E11cells and macrophage-like HD11 cells. Using mutant strains: S. Enteritidis fimH::kan and S. Gallinarum fimH::kan devoid of T1Fs and in vitro assays the following observations were made. MST1Fs have a significant impact on the chicken cell invasion by S. Enteritidis as MST1F-mediated adhesion facilitates direct and stable contact of bacteria with host cells, in contrast to MRT1Fs expressed by S. Gallinarum. MST1Fs as well as MRT1Fs did not affected intracellular viability of S. Enteritidis and S. Gallinarum. However, absolute numbers of intracellular viable wild-type S. Enteritidis were significantly higher than S. Enteritidis fimH::kan mutant and wild-type S. Gallinarum and S. Gallinarum fimH::kan mutant. These differences, reflecting the numbers of adherent and invading bacteria, underline the importance of MST1Fs in the pathogenicity of S. Enteritidis infections. The cytotoxicity of wild-type S. Enteritidis and its mutant devoid of MST1Fs to HD11 cells was essentially the same, despite the fact that the number of viable intracellular bacteria was significantly lower in the mutated strain. Using HD11 cells with similar number of intracellular wild-type S. Enteritidis and S. Enteritidis fimH::kan mutant, it was found that the lack of MST1Fs did not affect directly the cytotoxicity, suggesting that the increase in cytotoxicity of S. Enteritidis devoid of MST1Fs may be associated with crosstalk between T1Fs and other virulence factors.
Topics: Animals; Salmonella enteritidis; Mannose; Chickens; Glycoproteins; Salmonella Infections, Animal
PubMed: 37356296
DOI: 10.1016/j.psj.2023.102833 -
Frontiers in Veterinary Science 2023Most cases of chicken salmonellosis are caused by serovar Gallinarum biovars Gallinarum and Pullorum, which lead to a significant morbidity and fatality rate. Although...
Most cases of chicken salmonellosis are caused by serovar Gallinarum biovars Gallinarum and Pullorum, which lead to a significant morbidity and fatality rate. Although the conventional Kaufmann-White scheme is the reliable method for the serotyping of , it does not distinguish between closely related biotypes like . Pullorum and . Gallinarum. Herein, we conducted a single one-step multiplex PCR assay that can identify and distinguish between . Pullorum and . Gallinarum in an accurate manner. This PCR method was based on three genes, including for . Pullorum identification, for . Gallinarum identification, and as the genus-level reference gene for . By comparing . Pullorum to . Gallinarum and other serovars of study revealed that only the former has a deletion of 126 bp-region in the carboxyl terminus of . The gene does not exist in . Gallinarum. However, it is present in all other serotypes. The multiplex PCR approach utilizes unique sets of primers that are intended to specifically target these three different genes. The established PCR method was capable of distinguishing between the biovars Pullorum and Gallinarum from the 29 distinct serotypes as well as the 50 distinct pathogens that are not , showing excellent specificity and exclusivity. The minimal amount of bacterial cells required for PCR detection was 100 CFU, while the lowest level of genomic DNA required was 27.5 pg/μL for both . Pullorum and . Gallinarum. After being implemented on the clinical isolates collected from a poultry farm, the PCR test was capable of distinguishing the two biovars Pullorum and Gallinarum from the other strains. The findings of the PCR assay were in line with those of the traditional serotyping and biochemical identification methods. This new multiplex PCR could be used as a novel tool to reinforce the clinical diagnosis and differentiation of . Pullorum and . Gallinarum, particularly in high-throughput screening situations, providing the opportunity for early screening of infections and, as a result, more effective management of the illness among flocks.
PubMed: 37476820
DOI: 10.3389/fvets.2023.1220118 -
Poultry Science Oct 2023
Corrigendum to Mikolajczyk-Martinez, A. et al. 2023. Unraveling the role of type 1 fimbriae in Salmonella pathogenesis: insights from a comparative analysis of Salmonella Enteritidis and Salmonella Gallinarum. Poult. Sci. 102:102833.
PubMed: 37598550
DOI: 10.1016/j.psj.2023.102999