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The Canadian Veterinary Journal = La... Jul 1988
PubMed: 17423089
DOI: No ID Found -
Journal of Veterinary Science Sep 2017Oral fluid analysis for herd monitoring is of interest to the commercial pig production in Korea. The aim of this study was to investigate pathogen-positive rates and...
Oral fluid analysis for herd monitoring is of interest to the commercial pig production in Korea. The aim of this study was to investigate pathogen-positive rates and correlations among eight pathogens associated with porcine respiratory disease complex by analyzing oral fluid samples from 214 pig groups from 56 commercial farms. Samples collected by a rope-chewing method underwent reverse-transcriptase polymerase chain reaction (RT-PCR) or standard polymerase chain reaction (PCR) analysis, depending on the microorganism. Pathogens were divided into virus and bacteria groups. The former consisted of porcine reproductive and respiratory syndrome virus and porcine circovirus type 2 (PCV2), and the latter , , , (MHP), , and (SS). All pathogens were detected more than once by PCR. Age-based analysis showed the PCR-positive rate increased with increasing age for PCV2 and MHP, whereas SS showed the opposite. Correlations between pathogens were assessed among 36 different pair combinations; only seven pairs showed statistically significant correlations. In conclusion, the oral fluid method could be a feasible way to detect various swine respiratory disease pathogens and, therefore, could complement current monitoring systems for respiratory diseases in the swine industry.
Topics: Animals; Farms; Mouth; Porcine Reproductive and Respiratory Syndrome; Porcine respiratory and reproductive syndrome virus; Republic of Korea; Reverse Transcriptase Polymerase Chain Reaction; Surveys and Questionnaires; Swine
PubMed: 27586468
DOI: 10.4142/jvs.2017.18.3.283 -
Canadian Journal of Veterinary Research... Jan 1998Equine herpesvirus-1 (EHV-1) causes respiratory disease, neonatal death, abortion and neurologic disease. The main purpose of this study was to identify viral antigen in...
Equine herpesvirus-1 (EHV-1) causes respiratory disease, neonatal death, abortion and neurologic disease. The main purpose of this study was to identify viral antigen in respiratory tract samples by immunoperoxidase staining. Six pony foals were selected on the basis of demonstrating seronegativity to EHV-1 by virus neutralization and housed in isolation. They were infected experimentally by administering EHV-1 nebulized ultrasonically through a face mask. Successful infection was clinically apparent as each of the foals had febrile responses, nasal discharge, and enlarged submandibular lymph nodes. Sporadic coughing was also heard. EHV-1 was isolated from nasopharyngeal swabs of 4/6 ponies and seroconversion was demonstrated in all foals. Bronchoscopic examination of the large airways revealed hyperemia. The incidence of recovery of Actinobacillus suis from nasopharyngeal swabs increased initially, with recovery of Streptococcus zooepidemicus isolates predominating at 3 wk post-infection. Cytology brushes were used to sequentially sample the respiratory tract of the infected ponies at the nasopharynx, mid-trachea and the mainstem bronchus. Bronchoalveolar lavage provided lung cells. Immunocytochemistry techniques were applied to both types of samples to locate EHV-1 antigen. Indirect immunoperoxidase staining of samples utilizing monoclonal antibodies specific for EHV-1 demonstrated viral antigen associated with cellular debris, primarily in the nasopharyngeal samples on days 3-9 post-infection.
Topics: Aerosols; Animals; Antigens, Viral; Blood Cell Count; Cell Line; Female; Fibrinogen; Herpesviridae Infections; Herpesvirus 1, Equid; Horses; Immunohistochemistry; Male; Nasal Mucosa
PubMed: 9442940
DOI: No ID Found -
Applied and Environmental Microbiology Aug 2003Streptococcus suis serotype 2 is a major pathogen found in the upper respiratory tract of swine. In this study, isolates of this bacterial species were tested for the...
Streptococcus suis serotype 2 is a major pathogen found in the upper respiratory tract of swine. In this study, isolates of this bacterial species were tested for the production of bacteriocin-like inhibitory substances (BLIS). Of the 38 strains tested, four inhibited the growth of other S. suis isolates according to a deferred-antagonism plate assay. Interestingly, three of the strains were originally isolated from healthy carrier pigs and were considered nonvirulent. Three isolates (94-623, 90-1330, and AAH4) that produced BLIS in liquid broth were selected for further characterization. None of the inhibitory activities was related to the production of either organic acids or hydrogen peroxide. The BLIS produced by these strains were heat stable and proteinase K, pronase, and elastase sensitive but were trypsin and chymotrypsin resistant. They were stable at pH 2 and 12 and had molecular masses in the range of 14 to 30 kDa. Maximum production was observed during the mid-log phase. Following a curing procedure with novobiocin, only 90-1330 lost the ability to produce BLIS, suggesting that the BLIS might be plasmid encoded. Analysis of the inhibitory spectra revealed that the BLIS-producing strains also inhibited the growth of Actinobacillus minor, Actinobacillus porcinus, Enterococcus durans, Micrococcus luteus, Streptococcus agalactiae, Streptococcus dysgalactiae subsp. dysgalactiae, Streptococcus equi subsp. zooepidemicus, and S. dysgalactiae subsp. equisimilis. This study reports for the first time the ability of the swine pathogen S. suis serotype 2 to produce BLIS with the characteristics of classic bacteriocins. Further studies are required to investigate the possibility of using bacteriocin-producing strains to prevent swine infections caused by virulent strains of S. suis serotype 2.
Topics: Animals; Bacteria; Bacteriocins; Molecular Weight; Novobiocin; Streptococcus suis; Swine
PubMed: 12902232
DOI: 10.1128/AEM.69.8.4482-4488.2003 -
BMC Microbiology Jun 2016Actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, which causes important worldwide economic losses in the swine industry....
BACKGROUND
Actinobacillus pleuropneumoniae is the etiologic agent of porcine contagious pleuropneumonia, which causes important worldwide economic losses in the swine industry. Several respiratory tract infections are associated with biofilm formation, and A. pleuropneumoniae has the ability to form biofilms in vitro. Biofilms are structured communities of bacterial cells enclosed in a self-produced polymer matrix that are attached to an abiotic or biotic surface. Virtually all bacteria can grow as a biofilm, and multi-species biofilms are the most common form of microbial growth in nature. The goal of this study was to determine the ability of A. pleuropneumoniae to form multi-species biofilms with other bacteria frequently founded in pig farms, in the absence of pyridine compounds (nicotinamide mononucleotide [NMN], nicotinamide riboside [NR] or nicotinamide adenine dinucleotide [NAD]) that are essential for the growth of A. pleuropneumoniae.
RESULTS
For the biofilm assay, strain 719, a field isolate of A. pleuropneumoniae serovar 1, was mixed with swine isolates of Streptococcus suis, Bordetella bronchiseptica, Pasteurella multocida, Staphylococcus aureus or Escherichia coli, and deposited in 96-well microtiter plates. Based on the CFU results, A. pleuropneumoniae was able to grow with every species tested in the absence of pyridine compounds in the culture media. Interestingly, A. pleuropneumoniae was also able to form strong biofilms when mixed with S. suis, B. bronchiseptica or S. aureus. In the presence of E. coli, A. pleuropneumoniae only formed a weak biofilm. The live and dead populations, and the matrix composition of multi-species biofilms were also characterized using fluorescent markers and enzyme treatments. The results indicated that poly-N-acetyl-glucosamine remains the primary component responsible for the biofilm structure.
CONCLUSIONS
In conclusion, A. pleuropneumoniae apparently is able to satisfy the requirement of pyridine compounds through of other swine pathogens by cross-feeding, which enables A. pleuropneumoniae to grow and form multi-species biofilms.
Topics: Acetylglucosamine; Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Biofilms; Bordetella bronchiseptica; Culture Media; Deoxyribonuclease I; Endopeptidase K; Escherichia coli; In Situ Hybridization, Fluorescence; Microscopy, Confocal; NAD; Niacinamide; Nicotinamide Mononucleotide; Pasteurella multocida; Pyridines; Pyridinium Compounds; Species Specificity; Staphylococcus aureus; Stem Cells; Streptococcus suis; Swine; Swine Diseases
PubMed: 27349384
DOI: 10.1186/s12866-016-0742-3 -
Infection and Immunity Oct 2005Actinobacillus suis has emerged as an important opportunistic pathogen of high-health-status swine. A colonization challenge method was developed, and using PCR-based...
Actinobacillus suis has emerged as an important opportunistic pathogen of high-health-status swine. A colonization challenge method was developed, and using PCR-based signature-tagged transposon mutagenesis, 13 genes belonging to 9 different functional classes were identified that were necessary for A. suis colonization of the upper respiratory tract of swine.
Topics: Actinobacillus Infections; Actinobacillus suis; Animals; DNA Transposable Elements; Gene Expression Regulation, Bacterial; Genes, Bacterial; Mutagenesis, Insertional; Nasopharynx; Swine; Swine Diseases; Virulence
PubMed: 16177387
DOI: 10.1128/IAI.73.10.7032-7039.2005 -
Research in Microbiology Jun 2011Sequencing of yet unknown Haemophilus influenzae serotype c (Hic) and d (Hid) capsule synthesis regions II revealed four (ccs1-4) and five (dcs1-5) open reading frames,...
Sequence analysis of serotype-specific synthesis regions II of Haemophilus influenzae serotypes c and d: evidence for common ancestry of capsule synthesis in Pasteurellaceae and Neisseria meningitidis.
Sequencing of yet unknown Haemophilus influenzae serotype c (Hic) and d (Hid) capsule synthesis regions II revealed four (ccs1-4) and five (dcs1-5) open reading frames, respectively. The inferred gene functions were in line with capsular polysaccharide structures. One or more proteins encoded by the Hic capsule synthesis region II showed similarity to Actinobacillus pleuropneumoniae serotype 1 and Actinobacillus suis K1 enzymes. Orthologues to the complete operon were observed in Actinobacillus minor strain 202, where even the gene order was conserved. Furthermore, Ccs4 was related to the capsule O-acetyltransferase of Neisseria meningitidis serogroup W-135. For the Hid locus, similarities to Hie, Mannheimia haemolytica A1 and N. meningitidis serogroup A were identified and the succession of genes was similar in the different species. The resemblance of genes and gene organization found for Hic and Hid with other species suggested horizontal gene transfer during capsule evolution across the bacterial classes.
Topics: Bacterial Capsules; Bacterial Proteins; Evolution, Molecular; Haemophilus influenzae; Molecular Sequence Data; Neisseria meningitidis; Operon; Pasteurellaceae; Sequence Analysis, DNA
PubMed: 21513796
DOI: 10.1016/j.resmic.2011.04.002 -
Immunology Aug 2005Surfactant protein D (SP-D) is a pattern-recognition molecule of the innate immune system that recognizes various microbial surface-specific carbohydrate and lipid...
Surfactant protein D (SP-D) is a pattern-recognition molecule of the innate immune system that recognizes various microbial surface-specific carbohydrate and lipid patterns. In vitro data has suggested that this binding may lead to increased microbial association with macrophages and dendritic cells. The aim of the present in vivo study was to study the expression of porcine SP-D (pSP-D) in the lung during different pulmonary bacterial infections, and the effect of the routes of infection on this expression was elucidated. Furthermore, the aim was to study the in vivo spatial relationship among pSP-D, pathogens, phagocytic cells and dendritic cells. Lung tissue was collected from experimental and natural bronchopneumonias caused by Actinobacillus pleuropneumoniae or Staphylococcus aureus, and from embolic and diffuse interstitial pneumonia, caused by Staph. aureus or Arcanobacterium pyogenes and Streptococcus suis serotype 2, respectively. By comparing normal and diseased lung tissue from the same lungs, increased diffuse pSP-D immunoreactivity was seen in the surfactant in both acute and chronic bronchopneumonias, while such increased expression of pSP-D was generally not present in the interstitial pneumonias. Co-localization of pSP-D, alveolar macrophages and bacteria was demonstrated, and pSP-D showed a patchy distribution on the membranes of alveolar macrophages. SP-D immunoreactivity was intracellular in dendritic cells. The dendritic cells were identified by their morphology, the absence of macrophage marker immunoreactivity and the presence of dendritic cell marker immunoreactivity. Increased expression of pSP-D in the surfactant coincided with presence of pSP-D-positive dendritic cells in bronchus-associated lymphoid tissue (BALT), indicating a possible transport of pSP-D through the specialized M cells overlying (BALT). In conclusion, we have shown that pSP-D expression in the lung surfactant is induced by bacterial infection by an aerogenous route rather than by a haematogenous route, and that the protein interacts specifically with alveolar macrophages and with dendritic cells in microbial-induced BALT. The function of the interaction between pSP-D and dendritic cells in BALT remain unclear, but pSP-D could represent a link between the innate and adaptive immune system, facilitating the bacterial antigen presentation by dendritic cells in BALT.
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Bacterial Infections; Bronchi; Dendritic Cells; Immunohistochemistry; In Situ Hybridization, Fluorescence; Lung; Lung Diseases; Lymphoid Tissue; Pneumonia; Pulmonary Surfactant-Associated Protein D; Pulmonary Surfactants; Staphylococcal Infections; Streptococcal Infections; Swine
PubMed: 16011521
DOI: 10.1111/j.1365-2567.2005.02189.x -
Research in Microbiology Jun 1996A 14-kDa outer membrane protein (OMP) was purified from Actinobacillus pleuro-pneumoniae serotype 2. The protein strongly reacts with sera from pigs experimentally or...
A 14-kDa outer membrane protein (OMP) was purified from Actinobacillus pleuro-pneumoniae serotype 2. The protein strongly reacts with sera from pigs experimentally or naturally infected with any of the 12 serotypes of A. pleuropneumoniae. The gene encoding this protein was isolated from a gene library of A. pleuropneumoniae serotype 2 reference strain by immunoscreening. Expression of the cloned gene in Escherichia coli revealed that the protein is also located in the outer membrane fraction of the recombinant host. DNA sequence analysis of the gene reveals high similarity of the protein's amino acid sequence to that of the E. coli peptidoglycan-associated lipoprotein PAL, to the Haemophilus influenzae OMP P6 and to related proteins of several other Gram-negative bacteria. We have therefore named the 14-kDa protein PalA, and its corresponding gene, palA. The 20 amino-terminal amino acid residues of PalA constitute a signal sequence characteristic of membrane lipoproteins of prokaryotes with a recognition site for the signal sequence peptidase II and a sorting signal for the final localization of the mature protein in the outer membrane. The DNA sequence upstream of palA contains an open reading frame which is highly similar to the E. coli tolB gene, indicating a gene cluster in A. pleuropneumoniae which is very similar to the E. coli tol locus. The palA gene is conserved and expressed in all A. pleuropneumoniae serotypes and in A. lignieresii. A very similar palA gene is present in A. suis and A. equuli.
Topics: Actinobacillus pleuropneumoniae; Bacterial Outer Membrane Proteins; Base Sequence; DNA, Bacterial; Electrophoresis, Polyacrylamide Gel; Escherichia coli Proteins; Immunoblotting; In Vitro Techniques; Lipoproteins; Molecular Sequence Data; Peptidoglycan; Proteoglycans
PubMed: 8763621
DOI: 10.1016/0923-2508(96)84710-3 -
Genome Announcements Sep 2014The assembled and annotated genome of Actinobacillus suis ATCC 33415(T) is reported here. The 2,501,598-bp genome encodes 2,246 open reading frames (ORFs) with strain...
The assembled and annotated genome of Actinobacillus suis ATCC 33415(T) is reported here. The 2,501,598-bp genome encodes 2,246 open reading frames (ORFs) with strain variable incursion of an integrative conjugative element into a tRNA locus. Comparative analysis of the deduced gene set should inform our understanding of pathogenesis, genomic plasticity, and serotype variation.
PubMed: 25237027
DOI: 10.1128/genomeA.00926-14