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Frontiers in Cellular and Infection... 2022Respiratory infections seriously affect the swine industry worldwide. Co-infections of two vital pathogenic bacteria () and (), colonizing the respiratory tract often...
Respiratory infections seriously affect the swine industry worldwide. Co-infections of two vital pathogenic bacteria () and (), colonizing the respiratory tract often occurs in veterinary clinical practice. Moreover, our previous research found that and can form biofilm . The formation of a mixed biofilm not only causes persistent infections, but also increases the multiple drug resistance of bacteria, which brings difficulties to disease prevention and control. However, the methods for detecting and in co-infection and biofilm are immature. Therefore, in this study, primers and probes were designed based on the conservative sequence of gene and IVA gene. Then, a TaqMan duplex real-time PCR method for simultaneous detection of and was successfully established optimizing the reaction system and conditions. The specificity analysis results showed that this TaqMan real-time PCR method had strong specificity and high reliability. The sensitivity test results showed that the minimum detection concentration of and recombinant plasmid was 10 copies/μL, which is 100 times more sensitive than conventional PCR methods. The amplification efficiencies of and were 95.9% and 104.4% with R value greater than 0.995, respectively. The slopes of the calibration curves of absolute cell abundance of and were 1.02 and 1.09, respectively. The assays were applied to cultivated mixed biofilms and approximately 10 CFUs per biofilm were quantified when 10 CFUs planktonic bacteria of either or were added to biofilms. In summary, this study developed a TaqMan real-time PCR assay for specific, accurate quantification of or in mixed biofilms, which may help for the detection, prevention and control of diseases caused by a bacterial mixed infection involving and .
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Animals; Biofilms; Coinfection; Reproducibility of Results; Streptococcus suis; Swine; Swine Diseases
PubMed: 35992166
DOI: 10.3389/fcimb.2022.898412 -
Veterinary Record Open Dec 2022The Gram-negative bacterium is an agent of global importance to the swine industry and the cause of lethal respiratory or septicaemic disease in pigs of different ages....
OBJECTIVE
The Gram-negative bacterium is an agent of global importance to the swine industry and the cause of lethal respiratory or septicaemic disease in pigs of different ages. Between 2018 and 2019, seven commercial farms in western Canada experienced episodes of increased mortality due to infection in grower pigs. The goal of this work was to profile, with molecular methods, isolated from diseased pigs and to compare them to other isolates.
DESIGN
This inferential observational study used nine western Canadian strains obtained from diseased lungs ( = 6), heart ( = 2) and brain ( = 1) and whole genome sequencing was performed. Comparative genomic analyses were performed to characterise the genetic variability, antimicrobial resistance and the virulence genes present.
RESULTS
Compared to the reference strain (ATCC 33415), an increased number of RTX (repeats in the structural toxin) gene copies were identified in strains isolated from organs without a mucosal surface, thus theoretically harder to invade. Western Canadian strains did not harbour genes associated with resistance to antimicrobial agents used in swine production. Novel regions were also identified in the genomes of five of nine strains demonstrating recombination and emergence of novel strains.
CONCLUSIONS
The results obtained in this study were associated with the emergence of new lineages. An increased number of RTX toxin gene copies is suggested to be associated with increased virulence. This study will contribute to improve our understanding regarding and may help guide vaccine development and agent control measures.
PubMed: 36213600
DOI: 10.1002/vro2.45 -
Canadian Journal of Veterinary Research... Apr 1999In recent years, Actinobacillus suis, Haemophilus parasuis, and Streptococcus suis have emerged as important pathogens of swine, particularly in high health status... (Review)
Review
In recent years, Actinobacillus suis, Haemophilus parasuis, and Streptococcus suis have emerged as important pathogens of swine, particularly in high health status herds. Their association with a wide range of serious clinical conditions and has given rise to the moniker "suis-ide diseases." These organisms are early colonizers and, for that reason, are difficult to control by management procedures such as segregated early weaning. Vaccination, serodiagnostic testing, and even serotyping are complicated by the presence of multiple serotypes, cross-reactive antigens, and the absence of clear markers for virulence. In this review, we discuss our current understanding of the pathogenesis, epidemiology, and management of the causative agents of the "suis-ide diseases" of swine.
Topics: Actinobacillus Infections; Animals; Bacterial Vaccines; Haemophilus Infections; Streptococcal Infections; Streptococcus suis; Swine; Swine Diseases
PubMed: 10369563
DOI: No ID Found -
The Journal of Veterinary Medical... May 2022The species of the genus Actinobacillus have so far been associated with specific animal hosts, and A. suis sensu stricto, an opportunistic pathogen of swine, is rarely...
The species of the genus Actinobacillus have so far been associated with specific animal hosts, and A. suis sensu stricto, an opportunistic pathogen of swine, is rarely isolated from ruminants. We describe here the isolation of A. suis sensu stricto from a newborn calf that died on a dairy farm in Japan. Identification of the isolate was performed by phenotypic and genotypic characterization, with the latter consisting of nucleotide sequence analyses of the 16S rRNA gene plus three housekeeping genes, rpoB, infB and recN.
Topics: Actinobacillus; Actinobacillus Infections; Actinobacillus suis; Animals; Phylogeny; RNA, Ribosomal, 16S; Swine; Swine Diseases
PubMed: 35387957
DOI: 10.1292/jvms.22-0044 -
BMC Veterinary Research Dec 2023Accurate measurement of disease associated with endemic bacterial agents in pig populations is challenging due to their commensal ecology, the lack of disease-specific...
Detection and disease diagnosis trends (2017-2022) for Streptococcus suis, Glaesserella parasuis, Mycoplasma hyorhinis, Actinobacillus suis and Mycoplasma hyosynoviae at Iowa State University Veterinary Diagnostic Laboratory.
BACKGROUND
Accurate measurement of disease associated with endemic bacterial agents in pig populations is challenging due to their commensal ecology, the lack of disease-specific antemortem diagnostic tests, and the polymicrobial nature of swine diagnostic cases. The main objective of this retrospective study was to estimate temporal patterns of agent detection and disease diagnosis for five endemic bacteria that can cause systemic disease in porcine tissue specimens submitted to the Iowa State University Veterinary Diagnostic Laboratory (ISU VDL) from 2017 to 2022. The study also explored the diagnostic value of specific tissue specimens for disease diagnosis, estimated the frequency of polymicrobial diagnosis, and evaluated the association between phase of pig production and disease diagnosis.
RESULTS
S. suis and G. parasuis bronchopneumonia increased on average 6 and 4.3%, while S. suis endocarditis increased by 23% per year, respectively. M. hyorhinis and A. suis associated serositis increased yearly by 4.2 and 12.8%, respectively. A significant upward trend in M. hyorhinis arthritis cases was also observed. In contrast, M. hyosynoviae arthritis cases decreased by 33% average/year. Investigation into the diagnostic value of tissues showed that lungs were the most frequently submitted sample, However, the use of lung for systemic disease diagnosis requires caution due to the commensal nature of these agents in the respiratory system, compared to systemic sites that diagnosticians typically target. This study also explored associations between phase of production and specific diseases caused by each agent, showcasing the role of S. suis arthritis in suckling pigs, meningitis in early nursery and endocarditis in growing pigs, and the role of G. parasuis, A. suis, M. hyorhinis and M. hyosynoviae disease mainly in post-weaning phases. Finally, this study highlighted the high frequency of co-detection and -disease diagnosis with other infectious etiologies, such as PRRSV and IAV, demonstrating that to minimize the health impact of these endemic bacterial agents it is imperative to establish effective viral control programs.
CONCLUSIONS
Results from this retrospective study demonstrated significant increases in disease diagnosis for S. suis, G. parasuis, M. hyorhinis, and A. suis, and a significant decrease in detection and disease diagnosis of M. hyosynoviae. High frequencies of interactions between these endemic agents and with viral pathogens was also demonstrated. Consequently, improved control programs are needed to mitigate the adverse effect of these endemic bacterial agents on swine health and wellbeing. This includes improving diagnostic procedures, developing more effective vaccine products, fine-tuning antimicrobial approaches, and managing viral co-infections.
Topics: Humans; Swine; Animals; Mycoplasma hyorhinis; Mycoplasma hyosynoviae; Streptococcus suis; Actinobacillus suis; Mycoplasma Infections; Iowa; Retrospective Studies; Universities; Swine Diseases; Arthritis; Endocarditis
PubMed: 38087358
DOI: 10.1186/s12917-023-03807-w -
Veterinary Journal (London, England :... Sep 2004
Topics: Abortion, Veterinary; Actinobacillus suis; Animals; Swine; Swine Diseases
PubMed: 15301759
DOI: 10.1016/j.tvjl.2003.10.008 -
New Zealand Veterinary Journal Jun 1982Nineteen isolates of Actinobacillus suis were recovered from horses during the period October 1978-December 1980. Animals varied in age from a full term foetus to 12...
Nineteen isolates of Actinobacillus suis were recovered from horses during the period October 1978-December 1980. Animals varied in age from a full term foetus to 12 years. One isolate was obtained from the nose of an apparently healthy horse, the remainder were obtained from still-born foetuses (2), foals dying within a week of birth (5), older animals with respiratory (6) or genital infections (3) or abscesses in the jaw (1). One isolate was obtained from the lung of a 2-week-old foal which had shown diarrhoea. The bacteriological characteristics of the isolates and the pathological lesions present in eight cases are described. The organism has a wide geographical distribution in New Zealand, and in the northern part of the North Island appears to be more common than A. equuli.
PubMed: 16030875
DOI: 10.1080/00480169.1982.34889 -
The Journal of Veterinary Medical... Feb 2019Five-day-old neonatal piglets presented with debilitation and ananastasia. At the necropsy of one piglet, the apex of the tongue was found to be discolored dark red, and...
Five-day-old neonatal piglets presented with debilitation and ananastasia. At the necropsy of one piglet, the apex of the tongue was found to be discolored dark red, and disseminated white foci were found on the cut surface. Many white foci were also found in the lungs and on the serosa of the liver and spleen. Histopathological findings revealed multifocal necrotic glossitis and pneumonia with Gram-negative bacilli. The bacilli were identified as Actinobacillus suis through immunohistochemical, biochemical, and genetic tests, including 16S rRNA gene sequencing. Although A. suis usually causes inflammation in thoracic and abdominal organs, lesions were also found in the tongue in the present case. This study is the first report of glossitis caused by A. suis.
Topics: Actinobacillus Infections; Actinobacillus suis; Animals; Animals, Newborn; Glossitis; Necrosis; RNA, Ribosomal, 16S; Sepsis; Sequence Analysis, RNA; Tongue
PubMed: 30606907
DOI: 10.1292/jvms.18-0630 -
Biochemistry and Cell Biology =... Jun 2011The Gram-negative bacteria Actinobacillus suis colonizes the upper respiratory and genital tracts of swine. Along with capsular polysaccharides, lipopolysaccharides...
The Gram-negative bacteria Actinobacillus suis colonizes the upper respiratory and genital tracts of swine. Along with capsular polysaccharides, lipopolysaccharides (O-chain→core→lipid A~cell) are a main cell-surface component of A. suis. In this study, we determined that A. suis lipopolysaccharide incorporates a conserved core that shares some structural features with several core types of A. pleuropneumoniae . These common core structural features likely account for the observed serological cross-reactivity between A. suis and A. pleuropneumoniae, and the data suggest that the structural epitopes responsible for immunogenicity are those in the outer core domain.
Topics: Actinobacillus Infections; Actinobacillus pleuropneumoniae; Actinobacillus suis; Animals; Antibodies, Bacterial; Antigens, Bacterial; Antigens, Surface; Bacterial Capsules; Carbohydrate Sequence; Conserved Sequence; Lipopolysaccharides; Magnetic Resonance Spectroscopy; Mass Spectrometry; Models, Molecular; Molecular Sequence Data; O Antigens; Polysaccharides, Bacterial; Serotyping; Sus scrofa; Swine; Swine Diseases
PubMed: 21639829
DOI: 10.1139/o11-003 -
Microorganisms Sep 2023Antimicrobial resistance is an important health issue in human and veterinary medicine. The aim of this study was to monitor the antimicrobial resistance of three of the...
Antimicrobial resistance is an important health issue in human and veterinary medicine. The aim of this study was to monitor the antimicrobial resistance of three of the most important bacteria involved in porcine respiratory disease. A total of 465 isolates were tested during the 2017-2022 period for antimicrobial susceptibility for (n = 137), (n = 207), and (n = 121) by disk diffusion method. The results were interpreted by CLSI breakpoints, where available. High rates of susceptibility (from 90 to >99%) were observed for cefquinome, ceftiofur, amoxicillin + clavulanic acid, amoxicillin, penicillin, ampicillin, florfenicol, enrofloxacin, marbofloxacin, and trimethoprim-sulfamethoxazole. isolates showed high resistance to streptomycin (77%), gentamycin (45%), tilmicosin (39%) erythromycin (33%), oxytetracycline (19%), and tetracycline (18%). For , the highest rates of resistance were observed for streptomycin (98%), tetracycline (75%), oxytetracycline (72%), doxycycline (52%), and erythromycin (51%). presented a high rate of resistance for streptomycin (63%), tilmicosin (29%), oxytetracycline (13%), and tetracycline (14%). Bacteria isolates maintained high susceptibility against antimicrobial agents usually used against the mainly respiratory tract pathogens of swine. Resistance for streptomycin, tetracycline, oxytetracycline, and tilmicosin was high for all the tested pathogens.
PubMed: 37894069
DOI: 10.3390/microorganisms11102410