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Seakamela EM, Henton MM, Jonker A, Kayoka-Kabongo PN, Matle I. Temporal and Serotypic Dynamics of Actinobacillus pleuropneumoniae in South African Porcine Populations: A Retrospective Study from 1985 to 2023. Pathogens 2024; 13:599. [PMID: 39057825 PMCID: PMC11280335 DOI: 10.3390/pathogens13070599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2024] [Revised: 07/03/2024] [Accepted: 07/17/2024] [Indexed: 07/28/2024] Open
Abstract
Actinobacillus pleuropneumoniae is a major bacterial pathogen causing porcine pleuropneumoniae, which is a disease of notable economic impact and high fatality rates among pigs worldwide. It has been reported that 19 distinct serotypes of this bacterium exist. Despite its global prominence, there exists a scarcity of information regarding its prevalence and distribution in South Africa. Thus, this study used laboratory records to investigate the serotype diversity, temporal distribution, and seasonal patterns of A. pleuropneumoniae isolated from porcine samples spanning from 1985 to 2023 within South Africa. Data from laboratory registries of 354 cases, obtained from three veterinary laboratories in South Africa, were analyzed. The data were categorized into two-time frames: term 1, covering 1985 to 2001, and term 2, spanning from 2002 to 2023. The dataset identified 11 different serotypes, with serotype 7 being the most prevalent at 22.7% (n = 62), which was followed by serotype 5 at 13.8% (n = 42). The study highlighted variations in the prevalence of serotypes among diseased animals over a 38-year period. Serotypes 3, 5, 7 and 8 were commonly observed during this time, while serotype 4 was absent from 1985 to 2001, and serotypes 1, 6, and 10 were absent from 2002 to 2023. The distribution of serotypes showed a diverse variation in the age of affected animals, clinical manifestation, and seasonal occurrence. Key findings revealed that serotype 7 was the most prevalent across all seasons with the highest occurrence in winter. Additionally, Gauteng province showed the highest prevalence of various serotypes. The information collected during this study will serve as a baseline for future epidemiological studies as well as inform control strategies.
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Affiliation(s)
- Emmanuel M. Seakamela
- Bacteriology Division, Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria 0110, South Africa
| | - Marijke M. Henton
- Vetdiagnostix Veterinary Pathology Services, P.O. Box 13624, Cascades 3202, South Africa;
| | - Annelize Jonker
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria 0110, South Africa;
| | - Prudence N. Kayoka-Kabongo
- Department of Agriculture and Animal Health, College of Agriculture and Environmental Sciences, University of South Africa, Johannesburg 1710, South Africa;
| | - Itumeleng Matle
- Bacteriology Division, Agricultural Research Council, Onderstepoort Veterinary Research, Pretoria 0110, South Africa
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2
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Kuchiishi SS, Ramos Prigol S, Bresolin E, Fernandes Lenhard B, Pissetti C, García-Iglesias MJ, Gutiérrez-Martín CB, Martínez-Martínez S, Kreutz LC, Frandoloso R. Brazilian Clinical Strains of Actinobacillus pleuropneumoniae and Pasteurella multocida: Capsular Diversity, Antimicrobial Susceptibility ( In Vitro) and Proof of Concept for Prevention of Natural Colonization by Multi-Doses Protocol of Tildipirosin. Antibiotics (Basel) 2023; 12:1658. [PMID: 38136692 PMCID: PMC10740920 DOI: 10.3390/antibiotics12121658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2023] [Revised: 11/08/2023] [Accepted: 11/10/2023] [Indexed: 12/24/2023] Open
Abstract
One hundred Actinobacillus pleuropneumoniae (App) and sixty Pasteurella multocida subsp. multocida serogroup A (PmA) isolates were recovered from porcine pneumonic lungs collected from eight central or southern states of Brazil between 2014 and 2018 (App) or between 2017 and 2021 (PmA). A. pleuropneumoniae clinical isolates were typed by multiplex PCR and the most prevalent serovars were 8, 7 and 5 (43, 25% and 18%, respectively). In addition, three virulence genes were assessed in P. multocida isolates, all being positive to capA (PmA) and kmt1 genes, all negative to capD and toxA, and most of them (85%) negative to pfhA gene. The susceptibility of both pathogens to tildipirosin was investigated using a broth microdilution assay. The percentage of isolates susceptible to tildipirosin was 95% for App and 73.3% for PmA. The MIC50 values were 0.25 and 1 μg/mL and the MIC90 values were 4 and >64 μg/mL for App and PmA, respectively. Finally, a multiple-dose protocol of tildipirosin was tested in suckling piglets on a farm endemic for both pathogens. Tildipirosin was able to prevent the natural colonization of the tonsils by App and PmA and significantly (p < 0.0001) reduced the burden of Glaesserella parasuis in this tissue. In summary, our results demonstrate that: (i) tildipirosin can be included in the list of antibiotics to control outbreaks of lung disease caused by App regardless of the capsular type, and (ii) in the case of clinical strains of App and PmA that are sensitive to tildipirosin based on susceptibility testing, the use of this antibiotic in eradication programs for A. pleuropneumoniae and P. multocida can be strongly recommended.
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Affiliation(s)
- Suzana Satomi Kuchiishi
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
- Centro de Diagnóstico de Sanidade Animal—CEDISA, Concórdia 89727-000, Brazil;
| | | | - Eduarda Bresolin
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
- AFK Imunotech, Passo Fundo 99052-900, Brazil;
| | - Bianca Fernandes Lenhard
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
| | - Caroline Pissetti
- Centro de Diagnóstico de Sanidade Animal—CEDISA, Concórdia 89727-000, Brazil;
| | - María-José García-Iglesias
- Animal Health Department, Faculty of Veterinary Medicine, University of León, 24007 León, Spain; (M.-J.G.-I.); (C.-B.G.-M.); (S.M.-M.)
| | - César-Bernardo Gutiérrez-Martín
- Animal Health Department, Faculty of Veterinary Medicine, University of León, 24007 León, Spain; (M.-J.G.-I.); (C.-B.G.-M.); (S.M.-M.)
| | - Sonia Martínez-Martínez
- Animal Health Department, Faculty of Veterinary Medicine, University of León, 24007 León, Spain; (M.-J.G.-I.); (C.-B.G.-M.); (S.M.-M.)
| | - Luiz Carlos Kreutz
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
| | - Rafael Frandoloso
- Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Passo Fundo 99052-900, Brazil; (S.S.K.); (E.B.); (B.F.L.); (L.C.K.)
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3
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Ozawa M, Kawano M, Abo H, Issiki Y, Kumakawa M, Kawanishi M, Kojima A, Iwamoto S. Characterization of Actinobacillus pleuropneumoniae isolated from pigs in Japan using whole genome sequencing. Comp Immunol Microbiol Infect Dis 2023; 102:102062. [PMID: 37741218 DOI: 10.1016/j.cimid.2023.102062] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 09/05/2023] [Accepted: 09/08/2023] [Indexed: 09/25/2023]
Abstract
We conducted whole-genome sequencing to investigate the serotypes, the presence of virulence and antimicrobial resistance genes, and the genetic relationships among isolates of Actinobacillus. pleuropneumoniae derived from diseased pigs. Serotype 2 (71.2%) was the most common, but the prevalence of serotypes 6 (13.6%) and 15 (6.8%) increased. Existing vaccines are considered ineffective on the isolates belonging to serotypes 6 and 15. The phylogenetic tree based on core genome single nucleotide polymorphisms showed that the isolates were clustered by serotype. Of the isolates, 62.5% did not have an antimicrobial resistance gene, including a florfenicol resistance gene, but 32.2% had a tetracycline resistance gene. The antimicrobial resistant phenotype and genotype were almost identical. The plasmid-derived contigs harbored resistance genes of aminoglycosides, tetracyclines, β-lactams, phenicols, or sulfonamides. It has been suggested that isolates with different genetic properties from vaccine strains are circulating; however, antimicrobial resistance may not be widespread.
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Affiliation(s)
- Manao Ozawa
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan.
| | - Motoshi Kawano
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan
| | - Hitoshi Abo
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan
| | - Yukari Issiki
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan
| | - Mio Kumakawa
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan
| | - Michiko Kawanishi
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan
| | - Akemi Kojima
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan
| | - Shoko Iwamoto
- National Veterinary Assay Laboratory, Ministry of Agriculture, Forestry and Fisheries, 1-15-1, Tokura, Kokubunji, Tokyo 185-8511, Japan
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Donà V, Ramette A, Perreten V. Comparative genomics of 26 complete circular genomes of 18 different serotypes of Actinobacillus pleuropneumoniae. Microb Genom 2022; 8. [PMID: 35196217 PMCID: PMC8942016 DOI: 10.1099/mgen.0.000776] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Actinobacillus pleuropneumoniae is a Gram-negative, rod-shaped bacterium of the family Pasteurellaceae causing pig pleuropneumonia associated with great economic losses worldwide. Nineteen serotypes with distinctive lipopolysaccharide (LPS) and capsular (CPS) compositions have been described so far, yet complete circular genomes are publicly available only for the reference strains of serotypes 1, 4 and 5b, and for field strains of serotypes 1, 3, 7 and 8. We aimed to complete this picture by sequencing the reference strains of 17 different serotypes with the MinION sequencer (Oxford Nanopore Technologies, ONT) and on an Illumina HiSeq (Illumina) platform. We also included two field isolates of serotypes 2 and 3 that were PacBio- and MinION-sequenced, respectively. Genome assemblies were performed following two different strategies, i.e. PacBio- or ONT-only de novo assemblies polished with Illumina reads or a hybrid assembly by directly combining ONT and Illumina reads. Both methods proved successful in obtaining accurate circular genomes with comparable qualities. blast-based genome comparisons and core-genome phylogeny based on core genes, SNP typing and multi-locus sequence typing (cgMLST) of the 26 circular genomes indicated well-conserved genomes across the 18 different serotypes, differing mainly in phage insertions, and CPS, LPS and RTX-toxin clusters, which, consistently, encode serotype-specific antigens. We also identified small antibiotic resistance plasmids, and complete subtype I-F and subtype II-C CRISPR-Cas systems. Of note, highly similar clusters encoding all those serotype-specific traits were also found in other pathogenic and commensal Actinobacillus species. Taken together with the presence of transposable elements surrounding these loci, we speculate a dynamic intra- and interspecies exchange of such virulence-related factors by horizontal gene transfer. In conclusion, our comprehensive genomics analysis provides useful information for diagnostic test and vaccine development, but also for whole-genome-based epidemiological studies, as well as for the surveillance of the evolution of antibiotic resistance and virulence genes in A. pleuropneumoniae.
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Affiliation(s)
- Valentina Donà
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
| | - Alban Ramette
- Institute for Infectious Diseases, University of Bern, Bern, Switzerland
| | - Vincent Perreten
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, University of Bern, Bern, Switzerland
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5
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Pepovich R, Hristov K, Nikolov B, Genova K, Ivanova E, Kundurzhiev T, Tsachev I, Ciccozzi M, Baymakova M. Seroprevalence of Actinobacillus pleuropneumoniae infection in pigs from Bulgaria. BULGARIAN JOURNAL OF VETERINARY MEDICINE 2022. [DOI: 10.15547/bjvm.2020-0036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Actinobacillus pleuropneumoniae (App) is the etiological agent of porcine pleuropneumonia. The purpose of the study was to present a serological report on App prevalence among pigs in industrial farms in Bulgaria. Seventy-two pigs from four industrial farms in four districts of Bulgaria – Eastern Bulgaria (Razgrad and Yambol districts) and Western Bulgaria (Lovech and Sofia districts) were included. Animals were divided in two age groups: weaners and fattening pigs. A commercial enzyme-linked immunosorbent assay (ELISA, INgezim APP MIX, Eurofins Ingenasa, Madrid, Spain) for the detection of antibodies against App parasuis in porcine serum was used. Microtitrе plate was coated with App antigen of the serovars 1, 2, 9 and 11. Positive results for anti-App antibodies were detected in 32 (44.4%) of all 72 tested sera. The overall seropositivity in weaners and fattening pigs was 22.2% (8/36), and 66.7% (24/36), respectively. The highest App seropositivity in pigs was found in Eastern Bulgaria - 61.1% (22/36; P<0.001) in comparison to App seropositivity in Western Bulgaria – 27.8% (10/36; P=0.137). This study on anti-App prevalence among pigs in Bulgaria gives new insights on App epidemiology in our country.
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Affiliation(s)
- R. Pepovich
- Faculty of Veterinary Medicine, University of Forestry, Sofia, Bulgaria
| | - K. Hristov
- Faculty of Veterinary Medicine, University of Forestry, Sofia, Bulgaria
| | - B. Nikolov
- Faculty of Veterinary Medicine, University of Forestry, Sofia, Bulgaria
| | - K. Genova
- Faculty of Veterinary Medicine, University of Forestry, Sofia, Bulgaria
| | - E. Ivanova
- National Diagnostic and Research Veterinary Medical Institute, Sofia, Bulgaria
| | - T. Kundurzhiev
- Department of Occupational Medicine, Faculty of Public Health, Medical University, Sofia, Bulgaria
| | - I. Tsachev
- Department of Microbiology, Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, Trakia University, Stara Zagora, Bulgaria
| | - M. Ciccozzi
- Unit of Medical Statistics and Molecular Epidemio¬logy, Universita Campus Bio-Medico di Roma, Rome, Italy
| | - M. Baymakova
- Department of Infectious Diseases, Military Medical Academy, Sofia, Bulgaria
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6
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Zhang L, Xie H, Wang H, Ding H, Zhang G, Hu J. Kill Rate and Evaluation of Ex Vivo PK/PD Integration of Cefquinome Against Actinobacillus pleuropneumoniae. Front Vet Sci 2021; 8:751957. [PMID: 34966804 PMCID: PMC8710486 DOI: 10.3389/fvets.2021.751957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/12/2021] [Indexed: 11/13/2022] Open
Abstract
We wished to study the detailed and precise antibacterial activity of cefquinome against Actinobacillus pleuropneumoniae (APP) in vitro and ex vivo. We analyzed the relationships between kill rate and cefquinome concentration in broth and between pharmacokinetic/pharmacodynamic (PK/PD) parameters and antibacterial effect in serum and tissue cage fluid (TCF) of piglets. Cefquinome exhibited time-dependent antibacterial activity against APP according to the kill rate. The maximum kill rate was 0.48 log10 CFU/mL/h at the 0-9-h period in broth. In the ex vivo PK/PD study, the maximum concentration (Cmax), time to reach the maximum concentration (Tmax), terminal half-life (T1/2β), and area under the concentration time curve (AUCinfinity) were 5.65 μg/ml, 0.58 h, 2.24 h, and 18.48 μg·h/ml in serum and 1.13 μg/ml, 2.60 h, 12.22 h, and 20.83 μg·h/ml in TCF, respectively. The values of area under the curve during 24 h/minimum inhibitory concentration (AUC24h/MIC) for bacteriostatic, bactericidal, and bacterial eradication effects were 18.94, 246.8, and 1013.23 h in serum and 4.20, 65.81, and 391.35 h in TCF, respectively. Our findings will provide a valuable basis for optimization of dosage regimens when applying cefquinome to treat APP infection.
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Affiliation(s)
- Longfei Zhang
- Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, China.,College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China.,Postdoctoral Research Station, Henan Agriculture University, Zhengzhou, China
| | - Hongbing Xie
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China
| | - Hongjuan Wang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China
| | - Huanzhong Ding
- Guangdong Key Laboratory for Veterinary Drug Development and Safety Evaluation, South China Agricultural University, Guangzhou, China
| | - Gaiping Zhang
- Postdoctoral Research Station, Henan Agriculture University, Zhengzhou, China
| | - Jianhe Hu
- Postdoctoral Research Base, Henan Institute of Science and Technology, Xinxiang, China.,College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, China
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7
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Bossé JT, Li Y, Cohen LM, Stegger M, Angen Ø, Lacouture S, Gottschalk M, Lei L, Koene M, Kuhnert P, Bandara AB, Inzana TJ, Holden MTG, Harris D, Oshota O, Maskell DJ, Tucker AW, Wren BW, Rycroft AN, Langford PR, On Behalf Of The BRaDP T Consortium. Complete genome for Actinobacillus pleuropneumoniae serovar 8 reference strain 405: comparative analysis with draft genomes for different laboratory stock cultures indicates little genetic variation. Microb Genom 2021; 7. [PMID: 34818145 PMCID: PMC8743550 DOI: 10.1099/mgen.0.000687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report here the complete genome sequence of the widely studied Actinobacillus pleuropneumoniae serovar 8 reference strain 405, generated using the Pacific Biosciences (PacBio) RS II platform. Furthermore, we compared draft sequences generated by Illumina sequencing of six stocks of this strain, including the same original stock used to generate the PacBio sequence, held in different countries and found little genetic variation, with only three SNPs identified, all within the degS gene. However, sequences of two small plasmids, pARD3079 and p405tetH, detected by Illumina sequencing of the draft genomes were not identified in the PacBio sequence of the reference strain.
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Affiliation(s)
- Janine T Bossé
- Section of Paediatric Infectious Diseases, Department of Infectious Diseases, Imperial College London, London, UK
| | - Yanwen Li
- Section of Paediatric Infectious Diseases, Department of Infectious Diseases, Imperial College London, London, UK
| | - Liza Miriam Cohen
- Department of Production Animal Clinical Sciences Faculty of Veterinary Medicine, Norwegian University of Life Sciences, Ås, Norway
| | - Marc Stegger
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Øystein Angen
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Sonia Lacouture
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - Marcelo Gottschalk
- Groupe de Recherche sur les Maladies Infectieuses du Porc, Faculté de Médecine Vétérinaire, Université de Montréal, Québec, Canada
| | - Liancheng Lei
- College of Veterinary Medicine, Jilin University, Changchun, P.R China
| | - Miriam Koene
- Wageningen Bioveterinary Research, Lelystad, The Netherlands
| | - Peter Kuhnert
- Institute of Veterinary Bacteriology, Vetsuisse Faculty, Universität Bern, Bern, Switzerland
| | - Aloka B Bandara
- Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, USA
| | - Thomas J Inzana
- Present address: College of Veterinary Medicine, Long Island University, Brookville, USA.,Virginia-Maryland Regional College of Veterinary Medicine, Blacksburg, USA
| | - Matthew T G Holden
- Present address: School of Medicine, University of St Andrews, St Andrews, UK.,The Wellcome Trust Sanger Institute, Cambridge, UK
| | - David Harris
- The Wellcome Trust Sanger Institute, Cambridge, UK
| | - Olusegun Oshota
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Duncan J Maskell
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Alexander W Tucker
- Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Brendan W Wren
- Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK
| | - Andrew N Rycroft
- Department of Pathology and Pathogen Biology, The Royal Veterinary College, Hatfield, UK
| | - Paul R Langford
- Section of Paediatric Infectious Diseases, Department of Infectious Diseases, Imperial College London, London, UK
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Cohen LM, Bossé JT, Stegger M, Li Y, Langford PR, Kielland C, Klem TB, Gulliksen SM, Ranheim B, Grøntvedt CA, Angen Ø. Comparative Genome Sequence Analysis of Actinobacillus pleuropneumoniae Serovar 8 Isolates From Norway, Denmark, and the United Kingdom Indicates Distinct Phylogenetic Lineages and Differences in Distribution of Antimicrobial Resistance Genes. Front Microbiol 2021; 12:729637. [PMID: 34566934 PMCID: PMC8461171 DOI: 10.3389/fmicb.2021.729637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 08/13/2021] [Indexed: 11/13/2022] Open
Abstract
Actinobacillus pleuropneumoniae is the etiological agent of porcine pleuropneumonia, a disease of major impact on pig health, welfare, and productivity globally. Serovar 8 (APP) is the predominant clinical serovar in Norway and the United Kingdom (UK), and has been isolated from clinical cases in Denmark. The primary objective of this study was to characterize the genetic variability of isolates of A. pleuropneumoniae APP8 in the Norwegian population. The secondary objectives were to determine the within-host variability of APP8; to compare the APP8 bacterial populations in Norway, Denmark, and the UK, including antimicrobial resistance (AMR) gene profiles and to assess the effect of national differences in antimicrobial drug use and restricted animal movement on the occurrence of resistance. Isolates of APP8 from the UK (n=67), Denmark (n=22), and Norway (n=123) collected between 1983 and 2020 were compared using whole genome sequencing. To investigate genetic variability within individual hosts, an additional 104 APP8 isolates from the lungs of six Norwegian pigs were compared. Very low within-host variation was observed (≤ 2 single nucleotide polymorphisms). The phylogeny of 123 Norwegian APP8 isolates from 76 herds revealed some within-herd genetic variation, but substantial geographical clustering. When inferring the relatedness of the three international APP8 collections, the topology highlighted the existence of two distinct monophyletic branches characterized by the Norwegian and UK isolates, respectively. Three Danish isolates were scattered across the UK branch, whereas the remaining 19 Danish isolates clustered in two monophyletic groups nested in the Norwegian branch. Coalescence analysis, performed to estimate the divergences from a common ancestor, indicated a last common ancestor several centuries ago. The phylogenetic analyses also revealed striking differences in occurrence of AMR genes, as these were 23-times more prevalent among the UK isolates than among the Norwegian isolates. An increased understanding of the effects of population strategies is helpful in surveillance and control of infectious diseases.
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Affiliation(s)
- Liza Miriam Cohen
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | - Janine T Bossé
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Marc Stegger
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
| | - Yanwen Li
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Paul R Langford
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Camilla Kielland
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | | | | | - Birgit Ranheim
- Department of Production Animal Clinical Sciences, Faculty of Veterinary Medicine, Norwegian University of Life Sciences (NMBU), Oslo, Norway
| | | | - Øystein Angen
- Department of Bacteria, Parasites and Fungi, Statens Serum Institut, Copenhagen, Denmark
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9
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Stringer OW, Bossé JT, Lacouture S, Gottschalk M, Fodor L, Angen Ø, Velazquez E, Penny P, Lei L, Langford PR, Li Y. Rapid Detection and Typing of Actinobacillus pleuropneumoniae Serovars Directly From Clinical Samples: Combining FTA ® Card Technology With Multiplex PCR. Front Vet Sci 2021; 8:728660. [PMID: 34447805 PMCID: PMC8382971 DOI: 10.3389/fvets.2021.728660] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 07/12/2021] [Indexed: 11/13/2022] Open
Abstract
Actinobacillus pleuropneumoniae (APP), the causative agent of porcine pleuropneumonia, is highly contagious and responsible for high morbidity, mortality, and economic losses in the swine industry worldwide, but quick serotyping and diagnosis are still not widely available. In this study, we sought to validate the use of Whatman FTA® cards for collection and processing of A. pleuropneumoniae isolates, or porcine lung tissue samples, for direct use in diagnostic multiplex PCRs. We have optimized the processing of 3-mm discs punched from FTA® cards loaded with cultured A. pleuropneumoniae, or imprinted on lesioned regions of lung tissue, with only three distilled water washes before addition into our APP-multiplex PCR (mPCR) assay for rapid, low-cost identification and serotyping. DNA captured on FTA® cards generated the same diagnostic PCR results as DNA extracted using commercial kits for 85 A. pleuropneumoniae clinical isolate cultures and 22 lung samples. Additionally, bacterial DNA bound to FTA® cards was detectable by PCR after 6 months of storage at 37°C. This study provides simple, efficient, rapid, and practical sample processing for detection and molecular serotyping of A. pleuropneumoniae.
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Affiliation(s)
- Oliver W. Stringer
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Janine T. Bossé
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Sonia Lacouture
- Groupe de Recherche sur les Maladies Infectieuses en Production Animale, Faculty of Veterinary Medicine, University of Montreal, Montreal, QC, Canada
| | - Marcelo Gottschalk
- Groupe de Recherche sur les Maladies Infectieuses en Production Animale, Faculty of Veterinary Medicine, University of Montreal, Montreal, QC, Canada
| | - László Fodor
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
| | - Øystein Angen
- Department of Microbiology and Infection Control, Statens Serum Institut, Copenhagen, Denmark
| | | | - Paul Penny
- Ceva Animal Health Ltd., Amersham, United Kingdom
| | - Liancheng Lei
- College of Veterinary Medicine, Jilin University, Changchun, China
| | - Paul R. Langford
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
| | - Yanwen Li
- Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom
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Comparative Genomics of Actinobacillus pleuropneumoniae Serotype 8 Reveals the Importance of Prophages in the Genetic Variability of the Species. Int J Genomics 2020; 2020:9354204. [PMID: 32149072 PMCID: PMC7049842 DOI: 10.1155/2020/9354204] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Accepted: 01/03/2020] [Indexed: 12/30/2022] Open
Abstract
Actinobacillus pleuropneumoniae is the etiologic agent of porcine pleuropneumonia. Currently, there are 18 different serotypes; the serotype 8 is the most widely distributed in the United States, Canada, United Kingdom, and southeastern Brazil. In this study, genomes of seven A. pleuropneumoniae serotype 8 clinical isolates were compared to the other genomes of twelve serotypes. The analyses of serotype 8 genomes resulted in a set of 2352 protein-coding sequences. Of these sequences, 76.6% are present in all serotypes, 18.5% are shared with some serotypes, and 4.9% were differential. This differential portion was characterized as a series of hypothetical and regulatory protein sequences: mobile element sequence. Synteny analysis demonstrated possible events of gene recombination and acquisition by horizontal gene transfer (HGT) in this species. A total of 30 sequences related to prophages were identified in the genomes. These sequences represented 0.3 to 3.5% of the genome of the strains analyzed, and 16 of them contained complete prophages. Similarity analysis between complete prophage sequences evidenced a possible HGT with species belonging to the family Pasteurellaceae. Thus, mobile genetic elements, such as prophages, are important components of the differential portion of the A. pleuropneumoniae genome and demonstrate a central role in the evolution of the species. This study represents the first study done to understand the genome of A. pleuropneumoniae serotype 8.
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Pereira MF, Rossi CC, Seide LE, Martins Filho S, Dolinski CDM, Bazzolli DMS. Antimicrobial resistance, biofilm formation and virulence reveal Actinobacillus pleuropneumoniae strains' pathogenicity complexity. Res Vet Sci 2018; 118:498-501. [DOI: 10.1016/j.rvsc.2018.05.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 05/02/2018] [Accepted: 05/06/2018] [Indexed: 01/11/2023]
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Antenucci F, Fougeroux C, Bossé JT, Magnowska Z, Roesch C, Langford P, Holst PJ, Bojesen AM. Identification and characterization of serovar-independent immunogens in Actinobacillus pleuropneumoniae. Vet Res 2017; 48:74. [PMID: 29122004 PMCID: PMC5679336 DOI: 10.1186/s13567-017-0479-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 10/20/2017] [Indexed: 11/17/2022] Open
Abstract
Despite numerous actions to prevent disease, Actinobacillus pleuropneumoniae (A. pleuropneumoniae) remains a major cause of porcine pleuropneumonia, resulting in economic losses to the swine industry worldwide. In this paper, we describe the utilization of a reverse vaccinology approach for the selection and in vitro testing of serovar-independent A. pleuropneumoniae immunogens. Potential immunogens were identified in the complete genomes of three A. pleuropneumoniae strains belonging to different serovars using the following parameters: predicted outer-membrane subcellular localization; ≤ 1 trans-membrane helices; presence of a signal peptide in the protein sequence; presence in all known A. pleuropneumoniae genomes; homology with other well characterized factors with relevant data regarding immunogenicity/protective potential. Using this approach, we selected the proteins ApfA and VacJ to be expressed and further characterized, both in silico and in vitro. Additionally, we analysed outer membrane vesicles (OMVs) of A. pleuropneumoniae MIDG2331 as potential immunogens, and compared deletions in degS and nlpI for increasing yields of OMVs compared to the parental strain. Our results indicated that ApfA and VacJ are highly conserved proteins, naturally expressed during infection by all A. pleuropneumoniae serovars tested. Furthermore, OMVs, ApfA and VacJ were shown to possess a high immunogenic potential in vitro. These findings favour the immunogen selection protocol used, and suggest that OMVs, along with ApfA and VacJ, could represent effective immunogens for the prevention of A. pleuropneumoniae infections in a serovar-independent manner. This hypothesis is nonetheless predictive in nature, and in vivo testing in a relevant animal model will be necessary to verify its validity.
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Affiliation(s)
- Fabio Antenucci
- Department of Veterinary and Animal Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frb. C., 1-20, Building: 301, Copenhagen, Denmark
| | - Cyrielle Fougeroux
- Department of International Health, Immunology and Microbiology ISIM, University of Copenhagen, Øster Farigmagsgade 5, Bldg 22/23, København K, 1014, Copenhagen, Denmark
| | - Janine T Bossé
- Department of Medicine, St Mary's Campus, Imperial College London, 236 Wright Fleming Wing, London, UK
| | - Zofia Magnowska
- Department of Veterinary and Animal Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frb. C., 1-20, Building: 301, Copenhagen, Denmark
| | - Camille Roesch
- Izon Science Ltd, Bâtiment Laennec, 60 Avenue Rockefeller, 69008, Lyon, France
| | - Paul Langford
- Department of Medicine, St Mary's Campus, Imperial College London, 236 Wright Fleming Wing, London, UK
| | - Peter Johannes Holst
- Department of International Health, Immunology and Microbiology ISIM, University of Copenhagen, Øster Farigmagsgade 5, Bldg 22/23, København K, 1014, Copenhagen, Denmark
| | - Anders Miki Bojesen
- Department of Veterinary and Animal Sciences, University of Copenhagen, Stigbøjlen 4, 1870 Frb. C., 1-20, Building: 301, Copenhagen, Denmark.
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Sassu EL, Bossé JT, Tobias TJ, Gottschalk M, Langford PR, Hennig-Pauka I. Update on Actinobacillus pleuropneumoniae-knowledge, gaps and challenges. Transbound Emerg Dis 2017; 65 Suppl 1:72-90. [PMID: 29083117 DOI: 10.1111/tbed.12739] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Indexed: 12/15/2022]
Abstract
Porcine pleuropneumonia, caused by the bacterial porcine respiratory tract pathogen Actinobacillus pleuropneumoniae, leads to high economic losses in affected swine herds in most countries of the world. Pigs affected by peracute and acute disease suffer from severe respiratory distress with high lethality. The agent was first described in 1957 and, since then, knowledge about the pathogen itself, and its interactions with the host, has increased continuously. This is, in part, due to the fact that experimental infections can be studied in the natural host. However, the fact that most commercial pigs are colonized by this pathogen has hampered the applicability of knowledge gained under experimental conditions. In addition, several factors are involved in development of disease, and these have often been studied individually. In a DISCONTOOLS initiative, members from science, industry and clinics exchanged their expertise and empirical observations and identified the major gaps in knowledge. This review sums up published results and expert opinions, within the fields of pathogenesis, epidemiology, transmission, immune response to infection, as well as the main means of prevention, detection and control. The gaps that still remain to be filled are highlighted, and present as well as future challenges in the control of this disease are addressed.
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Affiliation(s)
- E L Sassu
- Department of Pathobiology, Institute of Immunology, University of Veterinary Medicine, Vienna, Austria
| | - J T Bossé
- Section of Paediatrics, Department of Medicine, Imperial College London, London, UK
| | - T J Tobias
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - M Gottschalk
- Department of Pathology and Microbiology, Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada
| | - P R Langford
- Section of Paediatrics, Department of Medicine, Imperial College London, London, UK
| | - I Hennig-Pauka
- Field Station for Epidemiology, University of Veterinary Medicine Hannover, Foundation, Bakum, Germany
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To H, Teshima K, Nagai S, Zielinski GC, Koyama T, Lee J, Bessone FA, Nagano T, Oshima A, Tsutsumi N. Characterization of Actinobacillus pleuropneumoniae field strains antigenically related to the 3-6-8-15 group from diseased pigs in Japan and Argentina. Rev Argent Microbiol 2017; 50:12-22. [PMID: 28886933 DOI: 10.1016/j.ram.2017.04.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/08/2017] [Accepted: 04/20/2017] [Indexed: 11/30/2022] Open
Abstract
The objectives of this study were to determine the serovar of a collection of Actinobacillus pleuropneumoniae strains within the 3-6-8-15 cross-reacting group and to analyze their phenotypic and genetic properties. Based on the serological tests, forty-seven field strains of Actinobacillus pleuropneumoniae isolated from lungs with pleuropneumonia lesions in Japan and Argentina were found to be serovars belonging to the 3-6-8-15 cross-reacting group. By using a capsule loci-based PCR, twenty-nine (96.7%) and one (3.3%) from Japan were identified as serovars 15 and 8, respectively, whereas seventeen (100%) from Argentina were identified as serovar 8. The findings suggested that serovars 8 and 15 were prevalent within the 3-6-8-15 cross-reacting group, in Argentina and Japan, respectively. Phenotypic analyses revealed that the protein patterns observed on SDS-PAGE and the lipopolysaccharide antigen detected by immunoblotting of the reference and field strains of serovars 8 and 15 were similar to each other. Genetic (16S rDNA, apxIIA, apxIIIA, cps, cpx genes, apx and omlA patterns) analyses revealed that the apxIIA and apxIIIA genes of the field strains of serovars 8 and 15 were similar to those of the reference strains of serovars 3, 4, 6, 8 and 15. The results obtained in the present study may be useful for the development of more effective vaccines against disease caused by A. pleuropneumoniae by including the homologous antigens to the most prevalent serovars in specific geographical areas.
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Affiliation(s)
- Ho To
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan.
| | - Kaho Teshima
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Shinya Nagai
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Gustavo C Zielinski
- Animal Health Group, Estacion Experimental Agropecuaria Marcos Juarez, INTA, CC n°21 (2580), Marcos Juarez, Province of Cordoba, Argentina.
| | - Tomohiro Koyama
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Jina Lee
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Fernando A Bessone
- Animal Health Group, Estacion Experimental Agropecuaria Marcos Juarez, INTA, CC n°21 (2580), Marcos Juarez, Province of Cordoba, Argentina
| | - Tetsuji Nagano
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Atsushi Oshima
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
| | - Nobuyuki Tsutsumi
- Nippon Institute for Biological Science, 9-2221-1 Shinmachi, Ome, Tokyo 198-0024, Japan
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16
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Dors A, Kowalczyk A, Pomorska-Mól M. Real-time quantitative PCR for detection and identification of Actinobacillus pleuropneumoniae serotype 2. J Vet Res 2016. [DOI: 10.1515/jvetres-2016-0038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Abstract
Introduction: Porcine pleuropneumonia inflicts important economic losses on most commercial herds. Detection of subclinical or chronic infection in animals still remains a challenge, as isolation and identification of A. pleuropneumoniae serotypes is difficult and quantification of the bacteria on agar plates is often almost impossible. The aim of the study was to develop and evaluate a serotype-specific quantitative TaqMan probe-based PCR for detection of serotype 2 in pig lungs, tonsils, and nasal swabs.
Material and Methods: The primers were designed from the capsular polysaccharide biosynthesis genes of A. pleuropneumoniae serotype 2. PCR specificity and sensitivity were evaluated using reference strains and several other bacterial species commonly isolated from pigs.
Results: The real-time qPCR for detection of A. pleuropneumoniae serotype 2 was highly specific and gave no false positives with other serotypes or different bacterial species of pig origin. The detection limit for pure culture was 1.2 × 104 CFU/mL, for lung tissue and nasal swabs it was 1.2 × 105 CFU/mL, and for tonsils - 1.2 × 105 CFU/mL.
Conclusion: The method can be used to serotype A. pleuropneumoniae isolates obtained during cultivation and to detect and identify A. pleuropneumoniae serotype 2 directly in nasal swabs and tonsil scrapings obtained from live pigs or lung tissue and tonsils collected post-mortem.
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Affiliation(s)
- Arkadiusz Dors
- Department of Swine Diseases, National Veterinary Research Institute, 24-100 Pulawy, Poland
| | - Andrzej Kowalczyk
- Department of Swine Diseases, National Veterinary Research Institute, 24-100 Pulawy, Poland
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Li Y, Bossé JT, Williamson SM, Maskell DJ, Tucker AW, Wren BW, Rycroft AN, Langford PR. Actinobacillus pleuropneumoniae serovar 8 predominates in England and Wales. Vet Rec 2016; 179:276. [PMID: 27531715 PMCID: PMC5036230 DOI: 10.1136/vr.103820] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/19/2016] [Indexed: 11/23/2022]
Affiliation(s)
- Y Li
- Section of Paediatrics, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - J T Bossé
- Section of Paediatrics, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - S M Williamson
- APHA-Bury St Edmunds, Rougham Hill, Bury St Edmunds, Suffolk IP33 2RX, UK
| | - D J Maskell
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - A W Tucker
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - B W Wren
- Faculty of Infectious & Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - A N Rycroft
- Department of Pathology and Pathogen Biology, Royal Veterinary College, Hawkshead Lane, North Mymms, Hertfordshire AL9 7TA, UK
| | - P R Langford
- Section of Paediatrics, Imperial College London, St Mary's Campus, London W2 1PG, UK
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Bossé JT, Li Y, Fernandez Crespo R, Chaudhuri RR, Rogers J, Holden MTG, Maskell DJ, Tucker AW, Wren BW, Rycroft AN, Langford PR. ICEApl1, an Integrative Conjugative Element Related to ICEHin1056, Identified in the Pig Pathogen Actinobacillus pleuropneumoniae. Front Microbiol 2016; 7:810. [PMID: 27379024 PMCID: PMC4908127 DOI: 10.3389/fmicb.2016.00810] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 05/12/2016] [Indexed: 12/26/2022] Open
Abstract
ICEApl1 was identified in the whole genome sequence of MIDG2331, a tetracycline-resistant (MIC = 8 mg/L) serovar 8 clinical isolate of Actinobacillus pleuropneumoniae, the causative agent of porcine pleuropneumonia. PCR amplification of virB4, one of the core genes involved in conjugation, was used to identify other A. pleuropneumoniae isolates potentially carrying ICEApl1. MICs for tetracycline were determined for virB4 positive isolates, and shotgun whole genome sequence analysis was used to confirm presence of the complete ICEApl1. The sequence of ICEApl1 is 56083 bp long and contains 67 genes including a Tn10 element encoding tetracycline resistance. Comparative sequence analysis was performed with similar integrative conjugative elements (ICEs) found in other members of the Pasteurellaceae. ICEApl1 is most similar to the 59393 bp ICEHin1056, from Haemophilus influenzae strain 1056. Although initially identified only in serovar 8 isolates of A. pleuropneumoniae (31 from the UK and 1 from Cyprus), conjugal transfer of ICEApl1 to representative isolates of other serovars was confirmed. All isolates carrying ICEApl1 had a MIC for tetracycline of 8 mg/L. This is, to our knowledge, the first description of an ICE in A. pleuropneumoniae, and the first report of a member of the ICEHin1056 subfamily in a non-human pathogen. ICEApl1 confers resistance to tetracycline, currently one of the more commonly used antibiotics for treatment and control of porcine pleuropneumonia.
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Affiliation(s)
- Janine T Bossé
- Section of Paediatrics, Department of Medicine, Imperial College London London, UK
| | - Yanwen Li
- Section of Paediatrics, Department of Medicine, Imperial College London London, UK
| | | | - Roy R Chaudhuri
- Department of Veterinary Medicine, University of Cambridge Cambridge, UK
| | - Jon Rogers
- Animal and Plant Health Agency Bury St Edmunds Suffolk, UK
| | - Matthew T G Holden
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton Cambridge, UK
| | - Duncan J Maskell
- Department of Veterinary Medicine, University of Cambridge Cambridge, UK
| | - Alexander W Tucker
- Department of Veterinary Medicine, University of Cambridge Cambridge, UK
| | - Brendan W Wren
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine London, UK
| | - Andrew N Rycroft
- Department of Pathology and Pathogen Biology, The Royal Veterinary College Hatfield, UK
| | - Paul R Langford
- Section of Paediatrics, Department of Medicine, Imperial College London London, UK
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Complete Genome Sequence of MIDG2331, a Genetically Tractable Serovar 8 Clinical Isolate of Actinobacillus pleuropneumoniae. GENOME ANNOUNCEMENTS 2016; 4:4/1/e01667-15. [PMID: 26823596 PMCID: PMC4732349 DOI: 10.1128/genomea.01667-15] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We report here the complete annotated genome sequence of a clinical serovar 8 isolate Actinobacillus pleuropneumoniae MIDG2331. Unlike the serovar 8 reference strain 405, MIDG2331 is amenable to genetic manipulation via natural transformation as well as conjugation, making it ideal for studies of gene function.
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Abstract
The introduction into a naïve herd of animals sub-clinically infected with Actinobacillus pleuropneumoniae (App) is frequently the cause of clinical pleuropneumonia and the identification of such infected herds is a priority in the control of disease. Different serological tests for App have been developed and a number of these are routinely used. Some are species-specific whereas others identify more specifically the serotype/serogroup involved which requires updated information about important serotypes recovered from diseased pigs in a given area/country. Serotyping methods based on molecular techniques have been developed lately and are ready to be used by most diagnostic laboratories. When non-conclusive serological results are obtained, direct detection of App from tonsils is sometimes attempted. This review addresses different techniques and approaches used to monitor herds sub-clinically infected by this important pathogen.
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Affiliation(s)
- Marcelo Gottschalk
- Department of Pathology and Microbiology, Swine and Poultry Infectious Disease Center (CRIPA), Groupe de Recherche sur les Maladies Infectieuses du Porc (GREMIP), Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Québec, Canada J2S 2M2.
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21
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Bossé JT, Li Y, Walker S, Atherton T, Fernandez Crespo R, Williamson SM, Rogers J, Chaudhuri RR, Weinert LA, Oshota O, Holden MTG, Maskell DJ, Tucker AW, Wren BW, Rycroft AN, Langford PR. Identification of dfrA14 in two distinct plasmids conferring trimethoprim resistance in Actinobacillus pleuropneumoniae. J Antimicrob Chemother 2015; 70:2217-22. [PMID: 25957382 PMCID: PMC4500777 DOI: 10.1093/jac/dkv121] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2014] [Accepted: 04/05/2015] [Indexed: 11/30/2022] Open
Abstract
Objectives The objective of this study was to determine the distribution and genetic basis of trimethoprim resistance in Actinobacillus pleuropneumoniae isolates from pigs in England. Methods Clinical isolates collected between 1998 and 2011 were tested for resistance to trimethoprim and sulphonamide. The genetic basis of trimethoprim resistance was determined by shotgun WGS analysis and the subsequent isolation and sequencing of plasmids. Results A total of 16 (out of 106) A. pleuropneumoniae isolates were resistant to both trimethoprim (MIC >32 mg/L) and sulfisoxazole (MIC ≥256 mg/L), and a further 32 were resistant only to sulfisoxazole (MIC ≥256 mg/L). Genome sequence data for the trimethoprim-resistant isolates revealed the presence of the dfrA14 dihydrofolate reductase gene. The distribution of plasmid sequences in multiple contigs suggested the presence of two distinct dfrA14-containing plasmids in different isolates, which was confirmed by plasmid isolation and sequencing. Both plasmids encoded mobilization genes, the sulphonamide resistance gene sul2, as well as dfrA14 inserted into strA, a streptomycin-resistance-associated gene, although the gene order differed between the two plasmids. One of the plasmids further encoded the strB streptomycin-resistance-associated gene. Conclusions This is the first description of mobilizable plasmids conferring trimethoprim resistance in A. pleuropneumoniae and, to our knowledge, the first report of dfrA14 in any member of the Pasteurellaceae. The identification of dfrA14 conferring trimethoprim resistance in A. pleuropneumoniae isolates will facilitate PCR screens for resistance to this important antimicrobial.
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Affiliation(s)
- Janine T Bossé
- Section of Paediatrics, Department of Medicine, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Yanwen Li
- Section of Paediatrics, Department of Medicine, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Stephanie Walker
- Section of Paediatrics, Department of Medicine, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Tom Atherton
- Section of Paediatrics, Department of Medicine, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Roberto Fernandez Crespo
- Section of Paediatrics, Department of Medicine, Imperial College London, St Mary's Campus, London W2 1PG, UK
| | - Susanna M Williamson
- Animal and Plant Health Agency (APHA) Bury St Edmunds, Rougham Hill, Bury St Edmunds, Suffolk IP33 2RX, UK
| | - Jon Rogers
- Animal and Plant Health Agency (APHA) Bury St Edmunds, Rougham Hill, Bury St Edmunds, Suffolk IP33 2RX, UK
| | - Roy R Chaudhuri
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Lucy A Weinert
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Olusegun Oshota
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Matt T G Holden
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK
| | - Duncan J Maskell
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Alexander W Tucker
- Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES, UK
| | - Brendan W Wren
- Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Andrew N Rycroft
- Department of Pathology and Pathogen Biology, The Royal Veterinary College, Hawkshead Campus, Hatfield, Hertfordshire AL9 7TA, UK
| | - Paul R Langford
- Section of Paediatrics, Department of Medicine, Imperial College London, St Mary's Campus, London W2 1PG, UK
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Draft Genome Sequences of Six Actinobacillus pleuropneumoniae Serotype 8 Brazilian Clinical Isolates: Insight into New Applications. GENOME ANNOUNCEMENTS 2015; 3:3/2/e01585-14. [PMID: 25745011 PMCID: PMC4358398 DOI: 10.1128/genomea.01585-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Actinobacillus pleuropneumoniae is the causative agent of swine pleuropneumonia, a highly contagious disease associated with pigs of all ages that results in severe economic losses to the industry. Here, we report for the first time six genome sequences of A. pleuropneumoniae clinical isolates of serotype 8, found worldwide.
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Pereira MF, Rossi CC, Vieira de Queiroz M, Martins GF, Isaac C, Bossé JT, Li Y, Wren BW, Terra VS, Cuccui J, Langford PR, Bazzolli DMS. Galleria mellonella is an effective model to study Actinobacillus pleuropneumoniae infection. MICROBIOLOGY-SGM 2014; 161:387-400. [PMID: 25414045 DOI: 10.1099/mic.0.083923-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Actinobacillus pleuropneumoniae is responsible for swine pleuropneumonia, a respiratory disease that causes significant global economic loss. Its virulence depends on many factors, such as capsular polysaccharides, RTX toxins and iron-acquisition systems. Analysis of virulence may require easy-to-use models that approximate mammalian infection and avoid ethical issues. Here, we investigate the potential use of the wax moth Galleria mellonella as an informative model for A. pleuropneumoniae infection. Genotypically distinct A. pleuropneumoniae clinical isolates were able to kill larvae at 37 °C but had different LD50 values, ranging from 10(4) to 10(7) c.f.u. per larva. The most virulent isolate (1022) was able to persist and replicate within the insect, while the least virulent (780) was rapidly cleared. We observed a decrease in haemocyte concentration, aggregation and DNA damage post-infection with isolate 1022. Melanization points around bacterial cells were observed in the fat body and pericardial tissues of infected G. mellonella, indicating vigorous cell and humoral immune responses close to the larval dorsal vessel. As found in pigs, an A. pleuropneumoniae hfq mutant was significantly attenuated for infection in the G. mellonella model. Additionally, the model could be used to assess the effectiveness of several antimicrobial agents against A. pleuropneumoniae in vivo. G. mellonella is a suitable inexpensive alternative infection model that can be used to study the virulence of A. pleuropneumoniae, as well as assess the effectiveness of antimicrobial agents against this pathogen.
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Affiliation(s)
- Monalessa Fábia Pereira
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Ciro César Rossi
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Marisa Vieira de Queiroz
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Gustavo Ferreira Martins
- Laboratório de Biologia Molecular de Insetos, Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Clement Isaac
- Department of Zoology, Ambrose Alli University, Akpoma, Nigeria.,Laboratório de Biologia Molecular de Insetos, Departamento de Biologia Geral, Universidade Federal de Viçosa, Viçosa, Brazil
| | - Janine T Bossé
- Section of Paediatrics, Imperial College London, London, UK
| | - Yanwen Li
- Section of Paediatrics, Imperial College London, London, UK
| | - Brendan W Wren
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Vanessa Sofia Terra
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | - Jon Cuccui
- Department of Pathogen Molecular Biology, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT, UK
| | | | - Denise Mara Soares Bazzolli
- Laboratório de Genética Molecular de Micro-organismos, Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária - BIOAGRO, Universidade Federal de Viçosa, Viçosa, Brazil
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24
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The generation of successive unmarked mutations and chromosomal insertion of heterologous genes in Actinobacillus pleuropneumoniae using natural transformation. PLoS One 2014; 9:e111252. [PMID: 25409017 PMCID: PMC4237320 DOI: 10.1371/journal.pone.0111252] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 09/26/2014] [Indexed: 12/24/2022] Open
Abstract
We have developed a simple method of generating scarless, unmarked mutations in Actinobacillus pleuropneumoniae by exploiting the ability of this bacterium to undergo natural transformation, and with no need to introduce plasmids encoding recombinases or resolvases. This method involves two successive rounds of natural transformation using linear DNA: the first introduces a cassette carrying cat (which allows selection by chloramphenicol) and sacB (which allows counter-selection using sucrose) flanked by sequences to either side of the target gene; the second transformation utilises the flanking sequences ligated directly to each other in order to remove the cat-sacB cassette. In order to ensure efficient uptake of the target DNA during transformation, A. pleuropneumoniae uptake sequences are added into the constructs used in both rounds of transformation. This method can be used to generate multiple successive deletions and can also be used to introduce targeted point mutations or insertions of heterologous genes into the A. pleuropneumoniae chromosome for development of live attenuated vaccine strains. So far, we have applied this method to highly transformable isolates of serovars 8 (MIDG2331), which is the most prevalent in the UK, and 15 (HS143). By screening clinical isolates of other serovars, it should be possible to identify other amenable strains.
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25
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Gottschalk M, Lacouture S. Actinobacillus pleuropneumoniae
serotypes 3, 6, 8 and 15 isolated from diseased pigs in North America. Vet Rec 2014; 174:452. [DOI: 10.1136/vr.102470] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- M. Gottschalk
- Department of Pathology and Microbiology; Faculty of Veterinary Medicine; University of Montreal; 3200 Sicotte, Saint-Hyacinthe Quebec Canada J2S 2M2
| | - S. Lacouture
- Department of Pathology and Microbiology; Faculty of Veterinary Medicine; University of Montreal; 3200 Sicotte, Saint-Hyacinthe Quebec Canada J2S 2M2
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26
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Multiplex PCR assay for unequivocal differentiation of Actinobacillus pleuropneumoniae serovars 1 to 3, 5 to 8, 10, and 12. J Clin Microbiol 2014; 52:2380-5. [PMID: 24759717 PMCID: PMC4097740 DOI: 10.1128/jcm.00685-14] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
An improved multiplex PCR, using redesigned primers targeting the serovar 3 capsule locus, which differentiates serovars 3, 6, and 8 Actinobacillus pleuropneumoniae isolates, is described. The new primers eliminate an aberrant serovar 3-indicative amplicon found in some serovar 6 clinical isolates. Furthermore, we have developed a new multiplex PCR for the detection of serovars 1 to 3, 5 to 8, 10, and 12 along with apxIV, thus extending the utility of this diagnostic PCR to cover a broader range of isolates.
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27
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Kuhnert P, Rohde J, Korczak BM. A new variant of Actinobacillus pleuropneumoniae serotype 3 lacking the entire apxII operon. J Vet Diagn Invest 2012; 23:556-9. [PMID: 21908290 DOI: 10.1177/1040638711404148] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Actinobacillus pleuropneumoniae is an important respiratory pathogen causing pleuropneumonia in pig. The species is genetically characterized by the presence of 4 RTX (Repeats in the Structural ToXin) toxin genes: apxI, apxII, and apxIII genes are differentially present in various combinations among the different serotypes, thereby defining pathogenicity; the apxIV gene is present in all serotypes. Polymerase chain reaction (PCR)-based apx gene typing is done in many veterinary diagnostic laboratories, especially reference laboratories. The present report describes the isolation of atypical A. pleuropneumoniae from 4 independent cases from 2 countries. All isolates were beta-nicotinamide adenine dinucleotide (β-NAD) dependent and nonhemolytic but showed strong co-hemolysis with the sphingomyelinase of Staphylococcus aureus on sheep blood agar. Classical biochemical tests as well as Matrix-assisted laser desorption ionization time-of-flight mass spectrometry and sequence-based analysis (16S ribosomal RNA [rRNA] and rpoB genes) identified them as A. pleuropneumoniae. Apx-toxin gene typing using 2 different PCR systems showed the presence of apxIV and only the apxIII operon (apxIIICABD). None of the apxI or apxII genes were present as confirmed by Southern blot analysis. The 16S rRNA and rpoB gene analyses as well as serotype-specific PCR indicate that the isolates are variants of serotype 3. Strains harboring only apxIV and the apxIII operon are possibly emerging types of A. pleuropneumoniae and should therefore be carefully monitored for epidemiological reasons.
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Affiliation(s)
- Peter Kuhnert
- Institute of Veterinary Bacteriology, University of Bern, Laenggassstr. 122, 3001 Bern, Switzerland.
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28
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BPEX Pig Health Scheme: a useful monitoring system for respiratory disease control in pig farms? BMC Vet Res 2011; 7:82. [PMID: 22208847 PMCID: PMC3285094 DOI: 10.1186/1746-6148-7-82] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2011] [Accepted: 12/30/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Respiratory diseases account for significant economic losses to the UK pig industry. Lesions indicative of respiratory disease in pig lungs at slaughter e.g. pneumonia and pleuritis are frequently recorded to assess herd health or provide data for epidemiological studies. The BPEX Pig Health Scheme (BPHS) is a monitoring system, which informs producers of gross lesions in their pigs' carcasses at slaughter, enabling farm-level decisions to be made. The aim of the study was to assess whether information provided by the BPHS regarding respiratory lesions was associated with respiratory pathogens in the farm, farm management practices and each other. RESULTS BPHS reports were obtained from a subset of 70 pig farms involved in a cross-sectional study conducted in 2008-09 investigating the epidemiology of post-weaning multi-systemic wasting syndrome. The reports were combined with data regarding the presence/absence of several pathogens in the herd and potential farm-level risk factors for respiratory disease. Principal component analysis (PCA) performed on BPHS reports generated three principal components, explaining 71% of the total variance. Enzootic pneumonia score, severe pleurisy and acute pleuropneumonia had the highest loadings for the principal component which explained the largest percentage of the total variance (35%) (BPHS component 1), it was thought that this component identifies farms with acute disease. Using the factor loadings a score for each farm for BPHS component 1 was obtained. As farms' score for BPHS component 1 increased, average carcass weight at slaughter decreased. In addition, farms positive for H1N2 and porcine reproductive and respiratory disease virus (PRRSV) were more likely to have higher levels of severe and mild pleurisy reported by the BPHS, respectively. CONCLUSIONS The study found statistical associations between levels of pleurisy recorded by BPHS at slaughter and the presence H1N2 and PRRSV in the herd. There is also some evidence that farms which submit pigs with these lesions may have reduced productivity. However, more research is needed to fully validate the scheme.
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29
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O’Neilla C, Jones SC, Bossé JT, Watson CM, Williamson SM, Rycroft AN, Simon Kroll J, Hartley HM, Langford PR. Population-based analysis of Actinobacillus pleuropneumoniae ApxIVA for use as a DIVA antigen. Vaccine 2010; 28:4871-4874. [PMID: 20483193 PMCID: PMC4843962 DOI: 10.1016/j.vaccine.2010.04.113] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 04/22/2010] [Accepted: 04/30/2010] [Indexed: 10/19/2022]
Abstract
APXIVA is an RTX toxin of Actinobacillus pleuropneumoniae that is a candidate antigen to differentiate infected from vaccinated animals (DIVA). Insertion of ISApl1 into the apxIVA gene is known to compromise an APXIVA-based DIVA approach, as is potentially a TGG to TGA mutation in the apxIVA gene. ISApl1 was found in 63/349 (18.1%) A. pleuropneumoniae isolates from England and Wales including serovars 2, 3, 6-8 and 12. No ISApl1 insertions into apxIVA were found. Only two serovar 3 isolates contained the TGG to TGA mutation. We conclude that an ApxIVA-based DIVA approach would potentially be viable in England and Wales.
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Affiliation(s)
- Ciaragh O’Neilla
- Molecular Infectious Diseases Group, Department of Paediatrics, Imperial College London, St Mary’s Campus, London, W2 1PG, UK
| | - Sophie C.P. Jones
- Molecular Infectious Diseases Group, Department of Paediatrics, Imperial College London, St Mary’s Campus, London, W2 1PG, UK
| | - Janine T. Bossé
- Molecular Infectious Diseases Group, Department of Paediatrics, Imperial College London, St Mary’s Campus, London, W2 1PG, UK
| | | | - Susanna M. Williamson
- Veterinary Laboratories Agency (VLA) Bury St Edmunds, Rougham Hill, Bury St Edmunds, Suffolk, IP33 2RX, UK
| | - Andrew N. Rycroft
- Department of Pathology and Infectious Diseases, Royal Veterinary College, Hawkshead Lane, North Mimms, Herts AL9 7TA, UK
| | - J. Simon Kroll
- Molecular Infectious Diseases Group, Department of Paediatrics, Imperial College London, St Mary’s Campus, London, W2 1PG, UK
| | | | - Paul R. Langford
- Molecular Infectious Diseases Group, Department of Paediatrics, Imperial College London, St Mary’s Campus, London, W2 1PG, UK
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