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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 -
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 -
International Journal of Molecular... Aug 2022(, Gram negative) and (.) (Gram positive) can cause severe diseases in pigs. During infection, neutrophils infiltrate to counteract these pathogens with phagocytosis...
(, Gram negative) and (.) (Gram positive) can cause severe diseases in pigs. During infection, neutrophils infiltrate to counteract these pathogens with phagocytosis and/or neutrophil extracellular traps (NETs). NETs consist of a DNA-backbone spiked with antimicrobial components. The NET formation mechanisms in porcine neutrophils as a response to both of the pathogens are not entirely clear. The aim of this study was to investigate whether (serotype 2, C3656/0271/11) and (serotype 2, strain 10) induce NETs by NADPH oxidase- or CD18-dependent mechanisms and to characterize phenotypes of NETs in porcine neutrophils. Therefore, we investigated NET induction in porcine neutrophils in the presence and absence of NET inhibitors and quantified NETs after 3 h. Furthermore, NETosis and phagocytosis were investigated by transmission electron microscopy after 30 min to characterize different phenotypes. and induce NETs that are mainly ROS-dependent. induces NETs that are partially CD18-dependent. Thirty minutes after infection, both of the pathogens induced a vesicular NET formation with only slight differences. Interestingly, some neutrophils showed only NET-marker positive phagolysosomes, but no NET-marker positive vesicles. Other neutrophils showed vesicular NETs and only NET-marker negative phagolysosomes. In conclusion, both of the pathogens induce ROS-dependent NETs. Vesicular NETosis and phagocytosis occur in parallel in porcine neutrophils in response to serotype 2 and serotype 2.
Topics: Animals; Bacterial Infections; Extracellular Traps; Neutrophils; Reactive Oxygen Species; Streptococcus suis; Swine
PubMed: 36012224
DOI: 10.3390/ijms23168953 -
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 -
Frontiers in Microbiology 2020() and () are primary swine pathogens that have been frequently co-isolated from pigs suffering from severe respiratory disease. The purpose of this study was to...
() and () are primary swine pathogens that have been frequently co-isolated from pigs suffering from severe respiratory disease. The purpose of this study was to investigate the biological impacts of the interactions between and . A single- and dual-species culture model was established via HA9801 (serotype 2) and CVCC265 (serotype 1). The single or mixed biofilms were imaged by confocal laser scanning microscopy. The biomass and viable cells in biofilms were quantified by crystal violet staining and determination of colony-forming units. The antibiotic susceptibility was determined by a microdilution broth method. The differences in gene transcription in pure- or mixed-species biofilms of and was evaluated by quantitative PCR. and formed two-species biofilms when co-cultured . When co-cultured with , biofilm formation by was significantly increased with the absence of NAD that is necessary for the growth of . Moreover, compared with monocultures, the antibiotic resistance of and was both enhanced in the co-culture model. When grown in dual-species biofilms, for , genes associated with virulence factors, including exotoxins and adhesins, were significantly upregulated. For , virulence factor-related genes , , , and were highly induced. These results suggest that the interspecies interactions between and may be cooperative under specific conditions and may play an important role in the disease progression and persistent infection.
PubMed: 32373078
DOI: 10.3389/fmicb.2020.00507 -
Animals : An Open Access Journal From... Oct 2023( HPS) is a prominent pathogenic bacterium in pig production. Its infection leads to widespread fibrinous inflammation in various pig tissues and organs, often in...
( HPS) is a prominent pathogenic bacterium in pig production. Its infection leads to widespread fibrinous inflammation in various pig tissues and organs, often in conjunction with various respiratory virus infections, and leads to substantial economic losses in the pig industry. Therefore, the rapid diagnosis of this pathogen is of utmost importance. In this study, we used recombinase polymerase amplification (RPA) and clustered regularly interspaced short palindromic repeats (CRISPR) technology to establish a convenient detection and analysis system for that is fast to detect, easy to implement, and accurate to analyze, known as RPA-CRISPR/Cas12a analysis. The process from sample to results can be completed within 1 h with high sensitivity (0.163 pg/μL of DNA template, < 0.05), which is 10 -fold higher than the common PCR method. The specificity test results show that the RPA-CRISPR/Cas12a analysis of did not react with other common pig pathogens, including type II and IX, , , , , and ( < 0.0001). The RPA-CRISPR/Cas12a assay was applied to 15 serotypes of clinical samples through crude extraction of nucleic acid by boiling method, and all of the samples were successfully identified. It greatly reduces the time and cost of nucleic acid extraction. Moreover, the method allows results to be visualized with blue light. The accurate and convenient detection method could be incorporated into a portable format as point-of-care (POC) diagnostics detection for at the field level.
PubMed: 37958075
DOI: 10.3390/ani13213317 -
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 -
Frontiers in Veterinary Science 2022A few decades ago, porcine respiratory disease complex (PRDC) exerted a major economic impact on the global swine industry, particularly due to the adoption of intensive... (Review)
Review
A few decades ago, porcine respiratory disease complex (PRDC) exerted a major economic impact on the global swine industry, particularly due to the adoption of intensive farming by the latter during the 1980's. Since then, the emerging of porcine reproductive and respiratory syndrome virus (PRRSV) and of porcine circovirus type 2 (PCV2) as major immunosuppressive viruses led to an interaction with other endemic pathogens (e.g., .) in swine farms, thereby exacerbating the endemic clinical diseases. We herein, review and discuss various dynamic polymicrobial infections among selected swine pathogens. Traditional biosecurity management strategies through multisite production, parity segregation, batch production, the adoption of all-in all-out production systems, specific vaccination and medication protocols for the prevention and control (or even eradication) of swine diseases are also recommended. After the introduction of the African swine fever (ASF), particularly in Asian countries, new normal management strategies minimizing pig contact by employing automatic feeding systems, artificial intelligence, and robotic farming and reducing the numbers of vaccines are suggested. Re-emergence of existing swine pathogens such as PRRSV or PCV2, or elimination of some pathogens may occur after the ASF-induced depopulation. ASF-associated repopulating strategies are, therefore, essential for the establishment of food security. The "repopulate swine farm" policy and the strict biosecurity management (without the use of ASF vaccines) are, herein, discussed for the sustainable management of small-to-medium pig farms, as these happen to be the most potential sources of an ASF re-occurrence. Finally, the ASF disruption has caused the swine industry to rapidly transform itself. Artificial intelligence and smart farming have gained tremendous attention as promising tools capable of resolving challenges in intensive swine farming and enhancing the farms' productivity and efficiency without compromising the strict biosecurity required during the ongoing ASF era.
PubMed: 36504860
DOI: 10.3389/fvets.2022.1048861 -
BMC Research Notes Nov 2015Actinobacillus suis disease has been reported in a wide range of vertebrate species, but is most commonly found in swine. A. suis is a commensal of the tonsils of the...
BACKGROUND
Actinobacillus suis disease has been reported in a wide range of vertebrate species, but is most commonly found in swine. A. suis is a commensal of the tonsils of the soft palate of swine, but in the presence of unknown stimuli it can invade the bloodstream, causing septicaemia and sequelae such as meningitis, arthritis, and death. It is genotypically and phenotypically similar to A. pleuropneumoniae, the causative agent of pleuropneumonia, and to other members of the family Pasteurellaceae that colonise tonsils. At present, very little is known about the genes involved in attachment, colonisation, and invasion by A. suis (or related members of the tonsil microbiota).
RESULTS
Bioinformatic analyses of the A. suis H91-0380 genome were done using BASys and blastx in GenBank. Forty-seven putative adhesin-associated genes predicted to encode 24 putative adhesins were discovered. Among these are 6 autotransporters, 25 fimbriae-associated genes (encoding 3 adhesins), 12 outer membrane proteins, and 4 additional genes (encoding 3 adhesins). With the exception of 2 autotransporter-encoding genes (aidA and ycgV), both with described roles in virulence in other species, all of the putative adhesin-associated genes had homologues in A. pleuropneumoniae. However, the majority of the closest homologues of the A. suis adhesins are found in A. ureae and A. capsulatus--species not known to infect swine, but both of which can cause systemic infections.
CONCLUSIONS
A. suis and A. pleuropneumoniae share many of the same putative adhesins, suggesting that the different diseases, tissue tropism, and host range of these pathogens are due to subtle genetic differences, or perhaps differential expression of virulence factors during infection. However, many of the putative adhesins of A. suis share even greater homology with those of other pathogens within the family Pasteurellaceae. Similar to A. suis, these pathogens (A. capsulatus and A. ureae) cause systemic infections and it is tempting to speculate that they employ similar strategies to invade the host, but more work is needed before that assertion can be made. This work begins to examine adhesin-associated factors that allow some members of the family Pasteurellaceae to invade the bloodstream while others cause a more localised infection.
Topics: Actinobacillus suis; Adhesins, Bacterial; Computational Biology; Pasteurellaceae
PubMed: 26567540
DOI: 10.1186/s13104-015-1659-x