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Avian Pathology : Journal of the W.V.P.A Dec 2011Salmonella enterica serovar Gallinarum causes a severe systemic disease, fowl typhoid, primarily in chickens and turkeys, and it remains a disease of worldwide...
Salmonella enterica serovar Gallinarum causes a severe systemic disease, fowl typhoid, primarily in chickens and turkeys, and it remains a disease of worldwide significance. Multilocus variable-number tandem-repeat analysis (MLVA) has proved to be very useful for subtyping other Salmonella serovars. We describe the development of a simple MLVA assay for S. enterica serovar Gallinarum that is comparable with pulsed-field gel electrophoresis (PFGE) in resolution. The genome sequence of S. enterica serovar Gallinarum strain 287/91 was analysed for potential variable-number tandem repeats (VNTRs) and then polymerase chain reaction assays were developed to assess the variability of the loci. Four VNTR markers were selected and used in a multiplex fragment analysis assay. The stability of the VNTR markers was assessed by conducting in vitro passage experiments with two strains (95 clones per strain) over a 30-day period. A MLVA of 68 strains of S. enterica serovar Gallinarum based on the four VNTR loci distinguished 26 allelic profiles. The MLVA assay showed a Simpson's diversity index of 0.918, whereas PFGE analysis produced 23 patterns and had a diversity index of 0.874. Most importantly, the MLVA further discriminated strains having the same PFGE pattern. The MLVA assay is a highly discriminatory genotyping method for S. enterica serovar Gallinarum. Therefore, MLVA can be a useful addition to routine PFGE analysis for molecular epidemiological investigation of fowl typhoid.
Topics: Animals; Bacterial Typing Techniques; Electrophoresis, Gel, Pulsed-Field; Genetic Markers; Genetic Variation; Minisatellite Repeats; Polymerase Chain Reaction; Poultry; Salmonella enterica
PubMed: 22107089
DOI: 10.1080/03079457.2011.613915 -
Veterinary Microbiology Jan 2011Salmonella enterica subsp. enterica serovar Gallinarum biovars Gallinarum and Pullorum cause fowl typhoid and pullorum disease in avian species, respectively, and have...
Salmonella enterica subsp. enterica serovar Gallinarum biovars Gallinarum and Pullorum cause fowl typhoid and pullorum disease in avian species, respectively, and have been of considerable economic importance to the poultry industry in parts of the world. The definitive diagnosis of these diseases can be made only by isolation and identification of the causative agent. However, rapid identification of biovars Gallinarum and Pullorum is not easily feasible due to their common antigenic structure and genomic sequence similarity. We developed a duplex polymerase chain reaction (PCR) assay to identify and discriminate between strains of biovars Gallinarum and Pullorum. Duplex PCR primers were designed to target polymorphic regions of glgC and speC genes showing multiple mutations in the sequenced S. enterica subsp. enterica serovar Gallinarum 287/91 genome and were applied to the specific identification of biovars Gallinarum and Pullorum. Boiled lysates of 131 reference and field strains of Salmonella and other related Gram-negative bacteria were tested to validate the duplex PCR assay. All strains of biovars Gallinarum (n=53) and Pullorum (n=21) tested were correctly identified based on this assay (100% sensitivity) while the other strains (n=57) were PCR negative (100% specificity). These results demonstrate that a highly accurate biovar-specific duplex PCR assay can be performed for the rapid identification and discrimination of biovars Gallinarum and Pullorum from field isolates.
Topics: Animals; Bacterial Proteins; Base Sequence; Bird Diseases; Birds; Exotoxins; Genes, Bacterial; Molecular Sequence Data; Polymerase Chain Reaction; Reproducibility of Results; Salmonella Infections, Animal; Salmonella enterica; Sensitivity and Specificity; Sequence Alignment; Species Specificity
PubMed: 21111918
DOI: 10.1016/j.vetmic.2010.05.039 -
Veterinary Microbiology Jul 2012To investigate the role of non-hemagglutinating type 1 fimbriae in the pathogenesis of Salmonella Gallinarum, the isogenic mutant elaborating type 1 fimbriae with...
To investigate the role of non-hemagglutinating type 1 fimbriae in the pathogenesis of Salmonella Gallinarum, the isogenic mutant elaborating type 1 fimbriae with mannose-sensitive (MS) variant of the FimH adhesin from Salmonella Enteritidis and the mutant strain with no FimH expression were constructed. Their binding to chicken leukocytes in vitro and invasiveness in 1-day-old chicks were studied. Our results demonstrated that S. Gallinarum type 1 fimbriae with an endogenous variant of the FimH adhesin mediated mannose-resistant (MR) binding to avian leukocytes and did not bind to human epithelial cells. However, after allelic replacement of the FimH, mutated fimbriae with S. Enteritidis variant of the FimH adhesin bound to both cell types in a mannose-dependent manner. In chick model, S. Gallinarum expressing wild-type FimH variant colonized cecal tonsils and bursa of Fabricius more effectively and invaded the spleen and liver in greater numbers than S. Gallinarum fimH knockout strain or mutant expressing MS FimH variant from S. Enteritidis. The invasive potential of the latter was greatly reduced in chicks since no viable bacteria expressing MS variant of the adhesin could be recovered from intestinal lymphoid tissues or liver over a 6 days course of infection. Together, these results demonstrate that the S. Gallinarum type 1 fimbriae with the endogenous MR variant of the FimH protein increase systemic dissemination of S. Gallinarum and colonization of internal organs in chicks indicating the importance of these adhesive structures in the virulence of S. Gallinarum.
Topics: Adhesins, Bacterial; Animals; Chickens; Leukocytes; Mannose; Salmonella enteritidis; Virulence
PubMed: 22364838
DOI: 10.1016/j.vetmic.2012.01.029 -
Journal of Food Protection Jun 2009The present study is an overview of the role of vegetables as a transmission vehicle of Salmonella in Mexico. One hundred samples of each of 17 different vegetables were...
The present study is an overview of the role of vegetables as a transmission vehicle of Salmonella in Mexico. One hundred samples of each of 17 different vegetables were analyzed during a period of 18 months. Salmonella was isolated from 98 samples. Salmonella enterica serovar Typhimurium was isolated from the highest percentage of samples with typeable Salmonella isolates (23.9%), followed by S. enterica subsp. arizonae and Salmonella Choleraesuis each from 16.9%, Salmonella Gallinarum from 11.1%, Salmonella Anatum and S. enterica subsp. houtenae each from 9.7%, Salmonella Agona and Salmonella Edinburg each from 4.22%, Salmonella Enteritidis and S. enterica subsp. salamae each from 2.81%, and Salmonella Bongor, Salmonella Pullorum, Salmonella Typhi, and Salmonella C1 flagellar b each from 1.4%. Of the isolated bacteria, 27.6% were nontypeable strains. Salmonella was isolated from 12% of parsley samples, 11% of cilantro samples, 9% of broccoli samples, 9% of cauliflower samples, 9% of "papaloquelite" (Porophyllum ruderale) samples, 9% of purslane (Portulaca oleracea) samples, 7% of long lettuce samples, 7% of spinach samples, 7% of watercress samples, 6% of Chinese parsley samples, 4% of beet samples, 3% of celery samples, 3% of Romaine lettuce samples, 1% of cabbage samples, and 1% of potato samples. The presence of Salmonella Typhi in parsley is noteworthy. No Salmonella isolates were obtained from zucchini and onion. These results indicate that raw or minimally processed vegetables can be contaminated with Salmonella, leading to direct infection of consumers or cross-contamination of other foodstuffs. These contaminated vegetables can represent a severe health risk for the Mexican consumer.
Topics: Bacterial Typing Techniques; Colony Count, Microbial; Consumer Product Safety; Food Contamination; Food Microbiology; Humans; Mexico; Phylogeny; Prevalence; Risk Assessment; Salmonella; Salmonella Food Poisoning; Vegetables
PubMed: 19610340
DOI: 10.4315/0362-028x-72.6.1279 -
Journal of Microbiological Methods Mar 2000Salmonella enterica serotype gallinarum biotype gallinarum and biotype pullorum are non-motile and pathogenic avian strains. Biotype gallinarum causes fowl typhoid and...
Salmonella enterica serotype gallinarum biotype gallinarum and biotype pullorum are non-motile and pathogenic avian strains. Biotype gallinarum causes fowl typhoid and biotype pullorum is the cause of pullorum disease in chickens. The two biotypes could be differentiated based on biochemical characteristics. However, conventional culture and biochemical assays are time-consuming, laborious and need sterile laboratory practices. Although the two biotypes, gallinarum and pullorum are non-motile, they possess the phase 1 flagellin C gene. The variable regions of the flagellin C gene from 41 biotype pullorum and 52 biotype gallinarum were amplified by colony-PCR and analyzed by single strand conformational polymorphism (SSCP) method. Differences in SSCP electrophoretic patterns were confirmed by nucleotide sequencing. In addition, PCR-RFLP with Hinp1I was also successfully applied to differentiate the two biotypes. These results suggested that the variable regions of fliC could be used as a genetic marker to differentiate biotype gallinarum from biotype pullorum.
Topics: Animals; Bacterial Typing Techniques; Chickens; DNA, Bacterial; Flagellin; Genes, Bacterial; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Polymorphism, Single-Stranded Conformational; Poultry Diseases; Salmonella Infections, Animal; Salmonella enterica; Sequence Analysis, DNA
PubMed: 10739340
DOI: 10.1016/s0167-7012(99)00129-3 -
Canadian Journal of Veterinary Research... Jul 2002Detection of the specific Salmonella serovar Gallinarum, which is divided into the biovars Pullorum and Gallinarum, is compulsory under the national hygienic and...
Detection of the specific Salmonella serovar Gallinarum, which is divided into the biovars Pullorum and Gallinarum, is compulsory under the national hygienic and sanitary control regulations of France for breeding flocks whose offspring are exported. Our aim was to examine the suitability of bacteriologic and serologic methods routinely used in France to screen serum samples and organs for S. Gallinarum. Since bacteriologic reference techniques are designed to isolate the commonly occurring non-typhoid serovars, such as S. Typhimurium, S. Enteritidis, and others that cause outbreaks of foodborne illness, they may not be particularly suitable for detecting S. Pullorum and S. Gallinarum. This hypothesis was confirmed by the inoculation of 10-wk-old chickens and 1-d-old chicks with various strains of S. Pullorum and S. Gallinarum. The most reliable enrichment media were selenite cystine and Rappaport-Vassiliadis broths. Moreover, on the usual plating media, colonies were small, grew more slowly than the common serovars (in 48 h instead of 24 h), and had an unusual appearance. Since the rapid slide agglutination (RSA) test is based only on antigens from standard and variant strains of S. Pullorum, it may not readily detect S. Gallinarum. In our study, it detected infection in all 10-wk-old chickens inoculated with S. Pullorum strains but did not detect any antibodies against S. Gallinarum. Therefore, S. Gallinarum antigens must be added to the S. Pullorum antigens used in the RSA test in order to detect antibodies produced by birds infected with either biovar.
Topics: Agglutination Tests; Animals; Antibodies, Bacterial; Chickens; Feces; France; Liver; Poultry Diseases; Salmonella; Salmonella Infections, Animal; Specific Pathogen-Free Organisms; Spleen
PubMed: 12146886
DOI: No ID Found -
Veterinary Immunology and... Mar 2009Avian systemic salmonellosis is primarily caused by Salmonella enterica serovar Gallinarum and serovar Pullorum causing the diseases Fowl Typhoid and Pullorum Disease... (Review)
Review
Avian systemic salmonellosis is primarily caused by Salmonella enterica serovar Gallinarum and serovar Pullorum causing the diseases Fowl Typhoid and Pullorum Disease respectively. During infection interaction with the immune system occurs in three main phases. First is invasion via the gastrointestinal tract. Infection with S. Pullorum or S. Gallinarum does not cause substantial inflammation, unlike S. Typhimurium or S. Enteritidis. Through in vitro models it was found that S. Gallinarum does not induce expression of CXC chemokines or pro-inflammatory cytokines such as IL-1beta or IL-6, whilst in an in vivo model S. Pullorum infection leads to down-regulation of CXCLi1 and CXCLi2 in the ileum. The absence of flagella in S. Gallinarum and S. Pullorum means they are not recognised by TLR5, which is believed to play a key role in the initiation of inflammatory responses, though other pathogen-factors are likely to be involved. The second phase is establishing systemic infection. Salmonella invade macrophages and probably dendritic cells and are translocated to the spleen and liver, where replication occurs. Salmonella survival is dependent on the Salmonella pathogenicity island 2 type III secretion system, which inhibits antimicrobial activity by preventing fusion of lysosymes with the phagocytic vacuole and by modulation of MHC and cytokine expression. Studies in resistant and susceptible chicken lines have shown that the interaction with macrophages is central to the progression of infection or immunological clearance. Primary macrophages from resistant animals are more efficient in killing Salmonella through respiratory burst and by induction of cytokine expression including the initiation of protective Th1 responses that leads to the third phase. Where replication of Salmonella is not controlled the death of the animal usually results. If the innate immune system is not able to control replication then cellular and humoral responses, primarily mediated through Th1-associated cytokines, are able to clear infection. In S. Pullorum a significant number of animals develop persistent infection of splenic macrophages. Here we show preliminary evidence of modulation of adaptive immunity away from a Th1 response to facilitate the development of the carrier state. In carrier animals persistence may lead to reproductive tract and egg infection associated with a decline in CD4+ T cell numbers and function associated with the onset of sexual maturity in hens.
Topics: Animals; Carrier State; Chickens; Intestines; Poultry Diseases; Salmonella Infections, Animal; Salmonella enterica
PubMed: 19070366
DOI: 10.1016/j.vetimm.2008.10.295 -
Poultry Science May 2017Salmonella enterica serovar Gallinarum biovars Pullorum and Gallinarum represent the most common causative agents of chicken salmonellosis, which result in high...
Salmonella enterica serovar Gallinarum biovars Pullorum and Gallinarum represent the most common causative agents of chicken salmonellosis, which result in high mortality and morbidity throughout the world. It is difficult and laborious to discriminate these diseases based on biochemical or phenotypic methods. Herein, we report the development of a single nucleotide polymorphism (SNP) PCR-high resolution melt (PCR-HRM) assay for the detection and discrimination of both S. Pullorum and S. Gallinarun. The gene rfbS, which encodes a factor involved in the biosynthesis of ADP paratose in serogroup D of Salmonella, has been identified as a robust genetic marker for the identification of S. Pullorum and S. Gallinarun based on polymorphisms at positions 237 and 598. Therefore, PCR-HRM analyses were used to characterize this gene. A total of 15 reference and 33 clinical isolates of Salmonella and related Gram-negative bacteria were detected using 2 sets of primers. Our PCR-HRM assay could distinguish S. Pullorum from S. Gallinarun and other strains using the primer pair SP-237F/237R. Similarly, S. Gallinarun could be distinguished from S. Pullorum and other strains using primer set SG-598F/598R. These 2 assays showed high specificity (100%) for both S. Pullorum and S. Gallinarun; the sensitivity of these 2 assays was at least 100-fold greater than that of the allele-specific PCR assay. This present study demonstrated that HRM analysis represents a potent, simple, and economic tool for the rapid, specific, and sensitive detection of S. Pullorum and S. Gallinarun. Our approach also may aid efforts for purification of Avian Salmonella disease.
Topics: Animals; Chickens; Polymorphism, Single Nucleotide; Poultry Diseases; Real-Time Polymerase Chain Reaction; Salmonella Infections, Animal; Salmonella enterica; Serogroup
PubMed: 27837117
DOI: 10.3382/ps/pew400 -
Veterinary Microbiology May 2017Salmonella enterica serovar Gallinarum biovar Pullorum (S. Pullorum) is the cause of pullorum disease, characterized by white diarrhea, which leads to high mortality in...
Salmonella enterica serovar Gallinarum biovar Pullorum (S. Pullorum) is the cause of pullorum disease, characterized by white diarrhea, which leads to high mortality in poultry. In this study, we aimed to assess the genetic diversity of 655 S. Pullorum strains from 1962 to 2015 in China, Europe, and South America. A sequence typing scheme based on clustered regularly interspaced short palindromic repeats (CRISPR) was used to reveal the genetic relationships among these strains in this study. Overall, a total of 20 Pullorum sequence types (PSTs) of CRISPR were identified in the 655 isolates with PST7 (74%, 486/655) and PST3 (13%, 86/655) to be the most two frequent PSTs belonging to two different lineages, which confirmed the genetic conservation of S. Pullorum strains isolated from six provinces and two direct-controlled municipalities (Beijing and Shanghai) in China. However, the identification of seven new PSTs distributed in strains isolated since 2001 implied that genetic variation continues to develop in S. Pullorum. Interestingly, the whole-genome single-nucleotide polymorphism typing (WGST) of 96 strains out of the 655 isolates divided them into four lineages based on SNP analysis of core genomic sequence and exhibit good correspondence with the CRISPR subtyping method. Notably, 22 out of 26 isolates from Europe and South America were distributed in five distinctive PSTs (with no Chinese strains). Additionally, CRISPR data of spacers and their arrangement exhibit subtle but distinct specificity between different strains, and the dynamic adaptive nature of CRISPR loci provides critical insights into the evolution of S. Pullorum as the bacteria are influenced by their environment.
Topics: Animals; China; Cluster Analysis; Clustered Regularly Interspaced Short Palindromic Repeats; Evolution, Molecular; Phylogeny; Poultry; Poultry Diseases; Salmonella Infections, Animal; Salmonella enterica; Sequence Analysis, DNA; Serogroup
PubMed: 28619172
DOI: 10.1016/j.vetmic.2017.02.010 -
Microbial Pathogenesis Feb 1990We examined the compatibility of the Salmonella virulence plasmids of serovars choleraesuis, dublin, enteritidis, gallinarum and pullorum and the cryptic Salmonella...
The virulence plasmids of Salmonella serovars typhimurium, choleraesuis, dublin, and enteritidis, and the cryptic plasmids of Salmonella serovars copenhagen and sendai belong to the same incompatibility group, but not those of Salmonella serovars durban, gallinarum, give, infantis and pullorum.
We examined the compatibility of the Salmonella virulence plasmids of serovars choleraesuis, dublin, enteritidis, gallinarum and pullorum and the cryptic Salmonella plasmids of serovars copenhagen, durban, give, infantis and sendai, with the 90 kilobase pair (kb) virulence plasmid of S. typhimurium. The 90 kb virulence plasmid of S. typhimurium in the form of pWR33, a cointegrate of F'::Tn10lac+ts and the 90 kb virulence plasmid, was transferred by bacterial conjugation into the Salmonella strains (except for S. sendai). The compatibility of their plasmids with the 90 kb virulence plasmid of S. typhimurium was then tested. Separately, a 90 kb virulence plasmid tagged with Tn5 was transformed into the S. sendai strain. The 90 kb virulence plasmid of S. typhimurium was found to be incompatible with the plasmids of serovars choleraesuis, copenhagen, dublin, enteritidis, and sendai, but compatible with the plasmids of serovars durban, gallinarum, give, infantis, and pullorum.
Topics: Conjugation, Genetic; Electrophoresis, Agar Gel; Plasmids; Salmonella; Serotyping; Virulence
PubMed: 2348777
DOI: 10.1016/0882-4010(90)90074-z