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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 -
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 -
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 -
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 -
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 -
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 -
The Canadian Veterinary Journal = La... Dec 2020Medical records of 20 horses with a confirmed diagnosis of valvular endocarditis at the Ontario Veterinary College between January 1, 1993 and February 3, 2020 were...
Medical records of 20 horses with a confirmed diagnosis of valvular endocarditis at the Ontario Veterinary College between January 1, 1993 and February 3, 2020 were reviewed. The diagnosis was based on physical examination findings, complete blood (cell) count (CBC), serum biochemistry, echocardiography, blood culture, and post-mortem findings. Common presenting signs included tachycardia, pyrexia, weight loss, lameness/joint distension, and a heart murmur. Clinicopathological findings included leukocytosis, anemia, hypoalbuminemia, hyperglobulinemia, and elevated inflammatory markers. Culture from 5 horses yielded in 2 cases and in 1 case. Of the 20 horses included in this study, 17 were euthanized and 3 were treated. Only 1 case had follow-up more than 1 year after discharge.
Topics: Animals; Echocardiography; Endocarditis; Euthanasia, Animal; Horse Diseases; Horses; Ontario
PubMed: 33299245
DOI: No ID Found -
Microbiology Spectrum Mar 2023Porcine respiratory disease complex (PRDC) is a serious disease caused by multiple pathogens which inflicts huge economic losses on the pig industry. Investigating the...
Porcine respiratory disease complex (PRDC) is a serious disease caused by multiple pathogens which inflicts huge economic losses on the pig industry. Investigating the epidemiology of porcine respiratory bacterial pathogens (PRBPs) in specific geographic areas and exploring the antibiotic susceptibility of local strains will contribute to the prevention and control of PRDC. However, the epidemiology of PRBPs in Guangxi Province remains unclear, and existing diagnostic methods have multiple limitations, such as high costs and the detection of only a single pathogen at a time. In this study, we developed a multiplex PCR assay for Streptococcus suis, Glaesserella parasuis, Actinobacillus pleuropneumoniae, Pasteurella multocida, and Mycoplasma hyopneumoniae, and investigated the prevalence of PRBPs in pigs with respiratory symptoms in Guangxi Province. The isolates from positive samples were subjected to susceptibility tests to 16 antibiotics. Our results indicated that of the 664 samples from pigs with respiratory symptoms, 433 (65.21%), 320 (48.19%), 282 (42.47%), 23 (3.46%), and 9 (1.36%), respectively, carried each of these 5 pathogens; 533 samples were positive; and 377 (56.78%) carried multiple pathogens simultaneously. The dominant PRBPs in pigs with respiratory symptoms in Guangxi province were S. suis, G. parasuis, and A. pleuropneumoniae, which frequently co-infected swine herds. Most of the isolates (A. pleuropneumoniae, G. parasuis, S. suis, and P. multocida) were sensitive to cefquinome, ceftiofur, trimethoprim-sulfamethoxazole (TMP-SMX), and tiamulin antibiotics. We developed a rapid specific multiplex PCR assay for PRBPs. Our findings provide new information on the epidemiology of PRBPs in Guangxi Province and offer a reference for developing drug targets against PRDC. Pigs are closely associated with humans as the most common food animals and the vectors of numerous pathogens. PRDC, caused by multiple pathogens, is a serious disease that can cause growth retardation in swine and even sudden death. Due to the droplet transmission of PRBP and the similar clinical signs of different pathogen infections, most pig farms struggle to identify and control PRBPs, leading to the abuse of antibiotics. In addition, some PRBPs have the potential to infect humans and threaten human health. Therefore, this study developed a multiplex PCR method targeting PRBPs, investigated the prevalence of these pathogens, and tested their antibiotic susceptibility. Our studies have important implications for public health safety and the development of the pig industry.
PubMed: 36916923
DOI: 10.1128/spectrum.03971-22