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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 -
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 -
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 -
PloS One 2019Actinobacillus pleuropneumoniae, Pasteurella multocida and Streptococcus suis are prevalent bacterial causes of swine infections. Morbidity, mortality and positively...
Mutant prevention and minimum inhibitory concentration drug values for enrofloxacin, ceftiofur, florfenicol, tilmicosin and tulathromycin tested against swine pathogens Actinobacillus pleuropneumoniae, Pasteurella multocida and Streptococcus suis.
Actinobacillus pleuropneumoniae, Pasteurella multocida and Streptococcus suis are prevalent bacterial causes of swine infections. Morbidity, mortality and positively impacting the financial burden of infection occurs with appropriate antimicrobial therapy. Increasing antimicrobial resistance complicates drug therapy and resistance prevention is now a necessity to optimize therapy and prolong drug life. Mutant bacterial cells are said to arise spontaneously in bacterial densities of 107-109 or greater colony forming units/ml. Antibiotic drug concentration inhibiting growth of the least susceptible cell in these high density populations has been termed the mutant prevention concentration (MPC). In this study MPC and minimum inhibitory concentration (MIC) values of ceftiofur, enrofloxacin, florfenicol, tilmicosin and tulathromycin were determined against the swine pathogens A. pleuropneumoniae, P.multocida and S. suis. The following MIC90/MPC90 values (mg/L) for 67 A. pleuropneumoniae and 73 P. multocida strains respectively were as follows: A. pleuropneumoniae 0.031/0.5, ≤0.016/0.5, 0.5/2, 4/32, 2/32; P. multocida 0.004/0.25, 0.016/0.125, 0.5/0.5, 8/16, 0.5/1. For 33 S. suis strains, MIC90 values (mg/L) respectively were as follows: 1, 0.25, 4, ≥8 and ≥8. A total of 16 S. suis strains with MIC values of 0.063-0.5 mg/L to ceftiofur and 0.25-0.5 mg/L to enrofloxacin were tested by MPC; MPC values respectively were 0.5 and 1 mg/L respectively. MPC concentrations provide a dosing target which may serve to reduce amplification of bacterial subpopulations with reduced antimicrobial susceptibility. Drug potency based on MIC90 values was ceftiofur > enrofloxacin >florfenicol = tulathromycin > tilmicosin; based on MPC90 values was enrofloxacin > ceftiofur > tulathromycin > florfenicol ≥ tilmicosin.
Topics: Actinobacillus pleuropneumoniae; Animal Husbandry; Animals; Anti-Bacterial Agents; Cephalosporins; Disaccharides; Drug Resistance, Multiple, Bacterial; Enrofloxacin; Heterocyclic Compounds; Microbial Sensitivity Tests; Pasteurella multocida; Streptococcus suis; Swine; Swine Diseases; Thiamphenicol; Tylosin
PubMed: 30629633
DOI: 10.1371/journal.pone.0210154 -
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 -
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 -
Veterinary Medicine and Science Sep 2021Porcine respiratory disease complex (PRDC) is one of the most challenging health concerns for pig production worldwide. The aim of the present study was to determine the...
Porcine respiratory disease complex (PRDC) is one of the most challenging health concerns for pig production worldwide. The aim of the present study was to determine the prevalence of pathogens associated with PRDC, including porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus type 2 (PCV2) and bacterial agents, such as Streptococcus suis, Haemophilus parasuis and Actinobacillus pleuropneumoniae, in clinically healthy pigs in Eastern China. Molecular detection revealed positive single-pathogen detection rates of 59.9%, 27.2%, 52.3%, 33.2% and 0.4% for PCV2, PRRSV, S. suis, H. parasuis and A. pleuropneumoniae, respectively. Co-infection with more than one pathogen was frequently detected in these samples, with PCV2/S. suis, H. parasuis and PCV2/H. parasuis mixed infection rates of 35.4%, 33.2% and 21.6%, respectively, and PCV2/S. suis/H. parasuis and PRRSV/PCV2/S. suis co-infection rates of 21.6% and 6.2%, respectively. These results suggest that mixed infections are prevalent among PRDC cases in swine, which may pose a greater threat to the health of herds compared with single-pathogen infections.
Topics: Animals; Circoviridae Infections; Circovirus; Coinfection; Porcine Reproductive and Respiratory Syndrome; Swine; Swine Diseases
PubMed: 34032016
DOI: 10.1002/vms3.533 -
BMC Veterinary Research Dec 2019Optimal treatment and prudent use of antimicrobials for pigs is imperative to secure animal health and prevent development of critical resistance. An important step in...
BACKGROUND
Optimal treatment and prudent use of antimicrobials for pigs is imperative to secure animal health and prevent development of critical resistance. An important step in this one-health context is to monitor resistance patterns of important animal pathogens. The aim of this study was to investigate the antimicrobial resistance patterns of five major pathogens in Danish pigs during a period from 2004 to 2017 and elucidate any developments or associations between resistance and usage of antibiotics.
RESULTS
The minimum inhibitory concentration (MIC) for Escherichia coli, Actinobacillus pleuropneumoniae, Streptococcus suis, Bordetella bronchiseptica, and Staphylococcus hyicus was determined to representatives of antibiotic classes relevant for treatment or surveillance. Escherichia coli isolates were mostly sensitive to fluoroquinolones and colistin, whereas high levels of resistance were observed to ampicillin, spectinomycin, streptomycin, sulfonamides and tetracycline. While resistance levels to most compounds remained relatively stable during the period, resistance to florfenicol increased from 2.1% in 2004 to 18.1% in 2017, likely in response to a concurrent increase in usage. A temporal association between resistance and usage was also observed for neomycin. E. coli serovars O138 and O149 were generally more resistant than O139. For A. pleuropneumoniae, the resistance pattern was homogenous and predictable throughout the study period, displaying high MIC values only to erythromycin whereas almost all isolates were susceptible to all other compounds. Most S. suis isolates were sensitive to penicillin whereas high resistance levels to erythromycin and tetracycline were recorded, and resistance to erythromycin and trimethoprim increasing over time. For S. hyicus, sensitivity to the majority of the antimicrobials tested was observed. However, penicillin resistance was recorded in 69.4-88.9% of the isolates. All B. bronchiseptica isolates were resistant to ampicillin, whereas all but two isolates were sensitive to florfenicol. The data obtained have served as background for a recent formulation of evidence-based treatment guidelines for pigs.
CONCLUSIONS
Antibiotic resistance varied for some pathogens over time and in response to usage. Resistance to critically important compounds was low. The results emphasize the need for continuous surveillance of resistance patterns also in pig pathogenic bacteria.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Bacterial Infections; Denmark; Drug Resistance, Bacterial; Microbial Sensitivity Tests; Swine; Swine Diseases
PubMed: 31829171
DOI: 10.1186/s12917-019-2162-8 -
Antibiotics (Basel, Switzerland) May 2022Antimicrobial susceptibility testing is necessary to carry out antimicrobial stewardship but a limited number of drugs belonging to each antimicrobial family has to be...
Antimicrobial susceptibility testing is necessary to carry out antimicrobial stewardship but a limited number of drugs belonging to each antimicrobial family has to be tested for technical limitations and economic resources. In this study, we have determined the minimal inhibitory concentration, using microdilution following international standards (CLSI), for 490 Actinobacillus pleuropneumoniae, 285 Pasteurella multocida, 73 Bordetella bronchiseptica, 398 Streptococcus suis and 1571 Escherichia coli strains from clinical cases collected in Spain between 2018 and 2020. The antimicrobial susceptibility pattern was deciphered using a principal component analysis for each bacterium and a matrix correlation (high > 0.8, medium 0.5−0.8 and low < 0.5) was obtained for each pair of antimicrobials. No significant associations were observed between MIC patterns for different antimicrobial families, suggesting that co-selection mechanisms are not generally present in these porcine pathogens. However, a high correlation was observed between the fluroquinolones (marbofloxacin and enrofloxacin) for all mentioned pathogens and for ceftiofur and cefquinome for E. coli and S. suis. Moreover, a significant association was also observed for tetracyclines (doxycycline and oxytetracycline) and B. bronchiseptica and tildipirosin/tulathromycin for P. multocida. These results suggest that generally, a representative drug per antimicrobial class cannot be selected, however, for some drug−bug combinations, MIC values from one representative drug could be extrapolated to the whole antimicrobial family.
PubMed: 35625283
DOI: 10.3390/antibiotics11050638 -
Scientific Reports Feb 2023Antimicrobial resistance (AMR) is one of the major challenges of the century and should be addressed with a One Health approach. This study aimed to develop a tool that...
Antimicrobial resistance (AMR) is one of the major challenges of the century and should be addressed with a One Health approach. This study aimed to develop a tool that can provide a better understanding of AMR patterns and improve management practices in swine production systems to reduce its spread between farms. We generated similarity networks based on the phenotypic AMR pattern for each farm with information on important bacterial pathogens for swine farming based on the Euclidean distance. We included seven pathogens: Actinobacillus suis, Bordetella bronchiseptica, Escherichia coli, Glaesserella parasuis, Pasteurella multocida, Salmonella spp., and Streptococcus suis; and up to seventeen antibiotics from ten classes. A threshold criterion was developed to reduce the density of the networks and generate communities based on their AMR profiles. A total of 479 farms were included in the study although not all bacteria information was available on each farm. We observed significant differences in the morphology, number of nodes and characteristics of pathogen networks, as well as in the number of communities and susceptibility profiles of the pathogens to different antimicrobial drugs. The methodology presented here could be a useful tool to improve health management, biosecurity measures and prioritize interventions to reduce AMR spread in swine farming.
Topics: Animals; Swine; Anti-Bacterial Agents; Farms; Antimicrobial Stewardship; Drug Resistance, Bacterial; Bacteria; Anti-Infective Agents; Escherichia coli
PubMed: 36804990
DOI: 10.1038/s41598-023-29980-4