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1.
J Vet Sci ; 21(4): e57, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32735095

RESUMO

BACKGROUND: Streptococcus dysgalactiae subspecies equisimilis (SDSE) acts as an etiological agent for lameness, neurological signs, and high mortality in pigs. Despite its importance in pig industries and zoonotic potential, little is known about the effects of this pathogen. OBJECTIVES: This study aimed to determine the molecular characteristics and antimicrobial resistance of SDSE strains isolated from diseased pigs. METHODS: A total 11 SDSE isolates were obtained from diseased pigs. Bacterial identification, PCR for virulence genes, emm typing, and antimicrobial resistance genes, multilocus sequence typing, and antimicrobial susceptibility test were performed. RESULTS: Nine isolates were from piglets, and 8 showed lameness, sudden death, or neurological signs. The isolates were PCR-positive for sla (100%), sagA (100%), and scpA (45.5%), and only 1 isolate amplified the emm gene (stL2764). Eight different sequence types were detected, categorized into 2 clonal complexes and 4 singletons. All the isolates in this study were included in a small cluster, which also contained other strains derived from humans and horses. The minimum inhibitory concentrations for the tested beta-lactams were low, while those for macrolides, tetracyclines, and fluoroquinolones were relatively high. PCR analysis of the macrolide and tetracycline resistance genes demonstrated that the isolates carried erm(B) (18.2%, n = 2), mef(A/E) (9.1%, n = 1), tet(M) (18.2%, n = 2), and tet(O) (90.2%, n = 10). Two isolates presented a mutation in parC, which is associated with fluoroquinolone resistance. CONCLUSION: This study provided insight into swine-derived SDSE, as it is related to veterinary medicine, and elucidated its zoonotic potential, in the context of molecular epidemiology and antimicrobial resistance in public health.


Assuntos
Farmacorresistência Bacteriana/genética , Infecções Estreptocócicas/veterinária , Streptococcus/efeitos dos fármacos , Doenças dos Suínos/diagnóstico , Animais , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/veterinária , Tipagem de Sequências Multilocus/veterinária , República da Coreia , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Streptococcus/genética , Suínos , Doenças dos Suínos/microbiologia
2.
Arq. bras. med. vet. zootec. (Online) ; 72(4): 1213-1220, July-Aug. 2020. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1131481

RESUMO

Surgical site infections (SSIs) and antimicrobial resistance among pathogens causing SSI are a growing concern in veterinary hospitals. One major reason, the widespread use of antimicrobials, has led to increased incidence of SSIs. This study identified bacteria and resistance profiles to antimicrobials in the SSI cases diagnosed at the Surgical Clinic of Small Animals in the Veterinary Hospital, Federal University of Viçosa, Brazil. The main genus identified was Staphylococcus, followed by Escherichia, Enterococcus, Bacillus, Shigella, Citrobacter, Proteus, Morganella, Serratia, Enterobacter, Pseudomonas and Klebsiella were also found, but in small number. The results indicated the predominance of Gram-negative bacteria among the collected samples. Most of isolates identified were resistant to more than one of the following antimicrobials: ampicillin, tetracycline, enrofloxacin, amoxicillin/clavulanic acid and cephalotin. Of the 17 Staphylococcus sp. isolates, two (11.8%) were methicillin-resistant Staphylococcus aureus (MRSA) and 11 (64.7%) of them were methicillin-resistant Staphylococcus pseudintermedius (MRSP). There were bacterial genera identified with resistance to all tested antimicrobials in different proportions. This should alert veterinary hospitals to the emergence of multidrug-resistant bacteria and to the requirement for the revision of surgical protocols with regard to antimicrobial prophylaxis and therapy.(AU)


As infecções em sítio cirúrgico (ISCs) e a resistência bacteriana entre os patógenos relacionados constituem uma preocupação crescente nos hospitais veterinários. O aumento na incidência de ISCs possui forte relação com o uso amplo e disseminado de antibióticos. O presente estudo identificou bactérias e perfis de resistência a antibióticos nos casos de ISCs diagnosticados na Clínica Cirúrgica de Pequenos Animais do Hospital Veterinário da Universidade Federal de Viçosa, Brasil. O principal gênero identificado foi Staphylococcus, seguido pelos gêneros Escherichia, Enterococcus, Bacillus, Shigella, Citrobacter, Proteus, Morganella, Serratia, Enterobacter, Pseudomonas e Klebsiella, porém, em menor quantidade. Os resultados demonstraram a predominância de bactérias Gram-negativas entre as amostras coletadas. A maioria dos isolados identificados eram resistentes a um ou a mais de um dos seguintes antibióticos: ampicilina, tetraciclina, enrofloxacina, amoxicilina/ácido clavulânico e cefalotina. Entre os 17 isolados de Staphylococcus sp., dois (11,8%) eram Staphylococcus aureus resistentes à meticilina (SARM) e 11 (64,7%) eram Staphylococcus pseudintermedius resistentes à meticilina (SPRM). Houve identificação de gêneros bacterianos com diferentes proporções de resistência para todos os antibióticos avaliados. Esses achados devem alertar os hospitais veterinários para a emergência de bactérias multirresistentes e para a necessidade de revisar a profilaxia e a terapia antimicrobiana referente aos protocolos cirúrgicos.(AU)


Assuntos
Animais , Gatos , Cães , Resistência Microbiana a Medicamentos , Infecção Hospitalar/veterinária , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana/veterinária
3.
J Vet Sci ; 21(3): e40, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32476314

RESUMO

The purpose of this study was to investigate the high-level mupirocin resistance (HLMR) in Gram-positive bacteria isolated from companion animals. A total of 931 clinical specimens were collected from diseased pets. The detection of mupirocin-resistant bacteria and plasmid-mediated mupirocin resistance genes were evaluated by antimicrobial susceptibility tests, polymerase chain reactions, and sequencing analysis. Four-hundred and six (43.6%) bacteria were isolated and 17 (4.2%), including 14 staphylococci and 3 Corynebacterium were high-level mupirocin-resistant (MICs, ≥ 1,024 ug/mL) harboring mupA. Six staphylococci of HLMR strains had plasmid-mediated mupA-IS257 flanking regions. The results show that HLMR bacteria could spread in veterinary medicine in the near future.


Assuntos
Antibacterianos/farmacologia , Corynebacterium/efeitos dos fármacos , Farmacorresistência Bacteriana , Mupirocina/farmacologia , Staphylococcus/efeitos dos fármacos , Animais , Doenças do Gato/tratamento farmacológico , Gatos , Infecções por Corynebacterium/tratamento farmacológico , Doenças do Cão/tratamento farmacológico , Cães , Testes de Sensibilidade Microbiana/veterinária , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária , Infecções Estafilocócicas/tratamento farmacológico
4.
Vet J ; 259-260: 105474, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32553237

RESUMO

Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary agent of enzootic pneumonia, a chronic and economically important respiratory disease of pigs. Control and prevention of M. hyopneumoniae infections can be accomplished by optimization of management and housing conditions, and by vaccination. The present paper summarizes the current knowledge on the main characteristics and efficacy of antimicrobials used for the treatment of clinical M. hyopneumoniae infections, the in vitro and in vivo activities of these antimicrobials and the reported resistance mechanisms against some. Potentially active antimicrobials against M. hyopneumoniae include tetracyclines, macrolides, lincosamides, pleuromutilins, amphenicols, aminoglycosides, aminocyclitols and fluoroquinolones. Antimicrobial treatment can be administered either orally or parenterally. Based on the overall results of efficacy studies performed under experimental and/or field conditions, the majority of agents belonging to these antimicrobial classes improved clinical parameters (clinical signs, lung lesions) and reduced performance losses due to M. hyopneumoniae infection. Antimicrobials may, however, not be able to prevent infection or to eradicate the bacterium from the respiratory tract. The decision to medicate should, therefore, be considered carefully. M. hyopneumoniae shows an intrinsic resistance against ß-lactam antibiotics, sulfonamides and trimethoprim. A few reports have shown acquired antimicrobial resistance against some antibiotics, along with associated resistance mechanisms. The results of antimicrobial susceptibility testing are difficult to interpret in terms of treatment outcome, as no clinical breakpoints have been defined for M. hyopneumoniae.


Assuntos
Antibacterianos/uso terapêutico , Mycoplasma hyopneumoniae , Pneumonia Suína Micoplasmática/tratamento farmacológico , Animais , Farmacorresistência Bacteriana , Testes de Sensibilidade Microbiana/veterinária , Suínos
5.
Acta Vet Scand ; 62(1): 36, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32580735

RESUMO

BACKGROUND: Streptococcus suis is a major cause of meningitis, arthritis, and pneumonia in pigs worldwide, and an emerging pathogen in humans. In Sweden, S. suis has previously received little attention but has in recent years become increasingly recognized as affecting the pig production. The aim of the present study was to investigate the occurrence, serotypes and antimicrobial susceptibility of S. suis in Swedish grower pigs from herds with and without reported S. suis associated disease, as well as possible associations between S. suis associated disease and selected environmental and production factors. Swab samples were taken from the tonsils of clinically healthy 8-13-week-old grower pigs from ten case herds and ten control herds. Isolates were cultured, identified using MALDI-TOF MS, and serotyped using latex agglutination. The antimicrobial susceptibility of 188 isolates was tested using broth microdilution. Production data was gathered and environmental parameters were measured on the farms. RESULTS: Streptococcus suis was isolated from 95% of the sampled pigs in both the case and the control herds. Serotypes 3, 4, 5, 7, 9, 10, 11, 15, 16, and 17-34 were detected, although a majority of the isolates (81.5%) were non-typeable. There was less diversity among the serotypes isolated from the case herds than among those from the control herds; four and nine different serotypes, respectively. Isolates resistant to penicillin (3.8%) were reported for the first time in Sweden. Tetracycline resistance was common (88.4%). No association was noted between the production and the environmental factors investigated, and the carriership of S. suis. CONCLUSIONS: The carriership of S. suis was found to be higher in clinically healthy Swedish pigs than previously estimated, and for the first time, the presence of Swedish isolates resistant to penicillin was reported. Many of the most commonly disease-associated serotypes, e.g. serotypes 2, 9, 3, and 7, were detected in healthy grower pigs although further studies are needed to investigate the virulence of these isolates.


Assuntos
Infecções Estreptocócicas/veterinária , Streptococcus suis/isolamento & purificação , Doenças dos Suínos/epidemiologia , Animais , Antibacterianos/farmacologia , Feminino , Incidência , Testes de Sensibilidade Microbiana/veterinária , Sorogrupo , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/microbiologia , Streptococcus suis/classificação , Streptococcus suis/efeitos dos fármacos , Sus scrofa , Suécia/epidemiologia , Suínos , Doenças dos Suínos/microbiologia
6.
Appl Environ Microbiol ; 86(15)2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32471914

RESUMO

In order to estimate herd-level prevalence of extended-spectrum ß-lactamase/AmpC ß-lactamase (ESBL/AmpC)- and carbapenemase-producing commensal Escherichia coli in ruminants in the Basque Country (northern Spain), a cross-sectional survey was conducted in 2014 to 2016 in 300 herds using selective isolation. ESBL-/AmpC-producing E. coli was isolated in 32.9% of dairy cattle herds, 9.6% of beef cattle herds, and 7.0% of sheep flocks. No carbapenemase-producing E. coli was isolated. Phenotypic antimicrobial susceptibility determined by broth microdilution using EUCAST epidemiological cutoff values identified widespread coresistance to extended-spectrum cephalosporins and other antimicrobials (110/135 isolates), particularly tetracycline, sulfamethoxazole, trimethoprim, and ciprofloxacin. All isolates were susceptible to tigecycline, imipenem, meropenem, and colistin. The genomes of 66 isolates were sequenced using an Illumina NovaSeq 6000 and screened for antimicrobial resistance determinants against ResFinder and PointFinder. The plasmid/chromosomal locations of resistance genes were predicted with PlasFlow, and plasmid replicons were identified using PlasmidFinder. Fifty-two acquired resistance genes and point mutations in another four genes that coded for resistance to 11 antimicrobial classes were identified. Fifty-five genomes carried ESBL-encoding genes, bla CTX-M-14 being the most common, and 11 carried determinants of the AmpC phenotype, mostly the bla CMY-2 gene. Additionally, genes coding for ß-lactamases of the CTX-M group 9 were detected as well as the sporadic presence of bla SHV-12, bla CMY-4, and a point mutation in the ampC promoter. Only a bovine isolate coharbored more than one ESBL/AmpC genetic determinant (bla CTX-M-14 and a mutation in the ampC promoter), confirming its ESBL- and AmpC ß-lactamase-producing phenotype. Most ESBL/AmpC genes were located in IncI1 plasmids, which also carried a great variety of other antimicrobial resistance genes.IMPORTANCE Extended-spectrum ß-lactamase (ESBL)- and AmpC ß-lactamase (AmpC)-producing E. coli isolates have emerged in recent years as some of the fastest spreading antimicrobial resistance determinants in humans and food-producing animals, becoming a concern for animal and public health. This study provided insight into the prevalence of cefotaxime-resistant E. coli in cattle and sheep in the Basque Country and the associated genetic determinants of antimicrobial resistance. These constituted an important contribution to the limited repository of such data for cattle in the region and for sheep worldwide. Antimicrobial susceptibility testing by phenotypic and molecular methods is key in surveillance programs to enhance early detection of resistance development, monitor resistance trends, and provide guidance to clinicians in selecting the adequate therapy.


Assuntos
Antibacterianos/farmacologia , Doenças dos Bovinos/epidemiologia , Cefotaxima/farmacologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Doenças dos Ovinos/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Estudos Transversais , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Genótipo , Testes de Sensibilidade Microbiana/veterinária , Fenótipo , Prevalência , Ovinos , Doenças dos Ovinos/microbiologia , Espanha/epidemiologia
7.
Br Poult Sci ; 61(5): 550-556, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32329627

RESUMO

1. Campylobacteriosis is the leading cause of human bacterial gastroenteritis. Broilers are considered the most important source of human Campylobacter infection. In the 2008 European baseline survey Ireland had a 98% prevalence of campylobacter-contaminated broiler carcases. 2. Randomly-selected Campylobacter isolates (296 C. jejuni, 54 C. coli) recovered in 2017 and 2018, from Irish broiler neck skin and caeca were tested for their resistance to tetracycline, erythromycin, gentamicin, ciprofloxacin, nalidixic acid and streptomycin. 3. Overall, 45% of the Campylobacter spp. isolates tested were resistant to at least one antimicrobial. Tetracycline resistance (38%) was most prevalent in C. jejuni, followed by ciprofloxacin and nalidixic acid resistance (29%). In C. coli, resistance to ciprofloxacin and nalidixic acid (26%) was most prevalent followed by resistance to tetracycline (13%). Gentamicin resistance was undetected and resistance to streptomycin was low for C. jejuni (1%) and C. coli (4%). All C. jejuni isolates examined were erythromycin-sensitive, while 9% of C. coli isolates were erythromycin-resistant. Three multidrug-resistant C. coli isolates were recovered. 4. While antibiotic resistance rates were somewhat similar to figures reported nationally over the past 20 years, the prevalence of tetracycline resistance in C. jejuni has increased. The persistence of substantial ciprofloxacin resistance in the Irish broiler population was noteworthy, despite fluoroquinolones having been banned for growth promotion in Europe since 2006.


Assuntos
Infecções por Campylobacter , Campylobacter coli , Campylobacter jejuni , Campylobacter , Animais , Antibacterianos/farmacologia , Infecções por Campylobacter/tratamento farmacológico , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/veterinária , Galinhas , Farmacorresistência Bacteriana , Humanos , Irlanda/epidemiologia , Testes de Sensibilidade Microbiana/veterinária
8.
J Vet Sci ; 21(2): e32, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32233138

RESUMO

Levofloxacin pharmacokinetic profiles were evaluated in 6 healthy female rabbits after intravenous (I/V), intramuscular (I/M), or subcutaneous (S/C) administration routes at a single dose of 5 mg/kg in a 3 × 3 cross-over study. Plasma levofloxacin concentrations were detected using a validated Ultra Performance Liquid Chromatography method with a fluorescence detector. Levofloxacin was quantifiable up to 10 h post-drug administration. Mean AUC0-last values of 9.03 ± 2.66, 9.07 ± 1.80, and 9.28 ± 1.56 mg/h*L were obtained via I/V, I/M, and S/C, respectively. Plasma clearance was 0.6 mL/g*h after I/V administration. Peak plasma concentrations using the I/M and S/C routes were 3.33 ± 0.39 and 2.91 ± 0.56 µg/mL. Bioavailability values, after extravascular administration were complete, - 105% ± 27% (I/M) and 118% ± 40% (S/C). Average extraction ratio of levofloxacin after I/V administration was 7%. Additionally, levofloxacin administration effects on tear production and osmolarity were evaluated. Tear osmolarity decreased within 48 h post-drug administration. All 3 levofloxacin administration routes produced similar pharmacokinetic profiles. The studied dose is unlikely to be effective in rabbits; however, it was calculated that a daily dose of 29 mg/kg appears effective for I/V administration for pathogens with MIC < 0.5 µg/mL.


Assuntos
Anti-Infecciosos/farmacocinética , Levofloxacino/farmacocinética , Testes de Sensibilidade Microbiana/veterinária , Coelhos/metabolismo , Animais , Estudos Cross-Over , Injeções Intramusculares/veterinária , Injeções Intravenosas/veterinária , Injeções Subcutâneas/veterinária
9.
J Am Vet Med Assoc ; 256(7): 800-807, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32176585

RESUMO

OBJECTIVE: To describe the antimicrobial susceptibility patterns of the most commonly isolated bacteria cultured from synovial fluid samples from horses with suspected septic synovitis treated at an equine referral hospital between May 1, 2008, and September 24, 2017. SAMPLE: 131 synovial fluid samples from 108 client-owned horses. PROCEDURES: A retrospective medical record search was conducted to identify horses with suspected septic synovitis and results of synovial fluid bacterial culture and antimicrobial susceptibility testing. Data collected included signalment, known or suspected origin of synovial contamination, synovial structures affected, antimicrobial treatment, and results of synovial fluid cytologic evaluation and bacterial culture and susceptibility testing. Horses were grouped as adults (≥ 6 months old) or foals (< 6 months old). RESULTS: Results of bacterial culture were positive for 34 of 70 (49%) and 18 of 61 (30%) samples from 68 adult horses and 40 foals, respectively. Gram-positive bacteria were more common in adult horses, whereas gram-negative bacteria were more common in foals. No multidrug-resistant microorganisms were identified. For adult horses, 92% (23/25) of gram-positive isolates tested with penicillin and gentamicin were susceptible to the combination. For foals, 94% (15/16) of isolates tested with penicillin, gentamicin, or both had susceptibility to 1 or both antimicrobials. CONCLUSIONS AND CLINICAL RELEVANCE: Periodic review of bacterial profiles and antimicrobial susceptibility in horses with septic synovitis can help to detect early changes in bacterial pressure and antimicrobial resistance. Findings suggested that in the geographic area we serve, a combination of penicillin and gentamicin would be an effective empirical antimicrobial treatment for most horses with septic synovitis while results of bacterial culture and susceptibility are pending.


Assuntos
Doenças dos Cavalos/tratamento farmacológico , Sinovite/veterinária , Animais , Antibacterianos/uso terapêutico , Cavalos , Testes de Sensibilidade Microbiana/veterinária , Estudos Retrospectivos , Líquido Sinovial
10.
BMC Vet Res ; 16(1): 81, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32138735

RESUMO

BACKGROUND: Gamithromycin is a macrolide approved for the treatment of bovine and swine respiratory diseases. Our study aims to establish the clinical breakpoint and optimum dose regimen for gamithromycin against Haemophilus parasuis in piglets. RESULTS: Gamithromycin was well absorbed and fully bioavailable (87.2-101%) after intramuscular and subcutaneous administrations. The MICs of gamithromycin for 192 clinical H. parasuis isolates ranged from 0.008 to 128 mg/L and the epidemiological cutoff (ECOFF) was calculated as 1.0 mg/L. A large potentiation effect of serum on in vitro susceptibility of gamithromycin was observed for H. parasuis, with broth/serum ratios of 8.93 for MICs and 4.46 for MBCs, respectively. The postantibiotic effects were 1.5 h (1 × MIC) and 2.4 h (4 × MIC), and the postantibiotic sub-MIC effects ranged from 2.7 to 4.3 h. Gamithromycin had rapid and concentration-dependent killing against H. parasuis, and the AUC24h/MIC ratio correlated well with ex vivo efficacy (R2 = 0.97). The AUC24h/MIC targets in serum associated with bacteriostatic, bactericidal and eradication activities were 15.8, 30.3 and 41.2, respectively. The PK/PD-based population dose prediction indicated a probability of target attainment (PTA) for the current marketed dose (6 mg/kg) of 88.9% against H. parasuis. The calculated gamithromycin dose for a PTA ≥ 90% was 6.55 mg/kg. Based on Monte Carlo simulations, the PK/PD cutoff (COPD) was determined to be 0.25 mg/L. CONCLUSION: The determined cutoffs and PK/PD-based dose prediction will be of great importance in gamithromycin resistance surveillance and serve as an important step in the establishment of optimum dose regimen and clinical breakpoints.


Assuntos
Infecções por Haemophilus/veterinária , Haemophilus parasuis/efeitos dos fármacos , Macrolídeos/farmacologia , Doenças dos Suínos/tratamento farmacológico , Animais , Antibacterianos/administração & dosagem , Antibacterianos/farmacocinética , Antibacterianos/farmacologia , Área Sob a Curva , Infecções por Haemophilus/tratamento farmacológico , Injeções Intramusculares/veterinária , Injeções Subcutâneas/veterinária , Macrolídeos/administração & dosagem , Macrolídeos/farmacocinética , Masculino , Testes de Sensibilidade Microbiana/veterinária , Sus scrofa , Suínos
11.
Poult Sci ; 99(2): 1117-1123, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32029147

RESUMO

Colibacillosis, caused by Escherichia coli, is one of the most common bacterial diseases of chickens. The high incidence and considerable economic losses associated with colibacillosis make it a significant concern worldwide. In recent years, the efficacy of colistin has been severely impacted by the emergence of plasmid-mediated colistin resistance genes, especially mcr-1. Therefore, monitoring of antibiotic resistance, particularly colistin resistance, amongst E. coli strains is vitally important to the future growth and sustainability of the poultry industry. In this study, a total of 130 E. coli strains were isolated from the livers of chickens displaying symptoms of colibacillosis in Tai'an, China. Isolates were screened for their susceptibility to various antibiotics and for the presence of mobile colistin resistance genes and other antibiotic resistance genes. Overall, 75 (57.7%) isolates showed resistance to colistin and were positive for mcr-1. The mobile colistin resistance genes, mcr-2, -3, and -4, were not detected in this study. Of the 75 mcr-1-positive isolates, all (100%) also carried tetracycline resistance genes, 71 (94.7%) also contained genes associated with ß-lactam resistance, 59 (78.7%) contained aminoglycoside resistance genes, and 57 (76%) contained sulfonamide resistance genes. This high prevalence of multidrug resistance among mcr-1-positive E. coli isolates, including the production of extended-spectrum ß-lactamases, is highly concerning. The surveillance findings presented here will be conducive to our understanding of the prevalence and characteristics of multidrug-resistance in E. coli in the Tai'an area and will provide a better scientific basis for the clinical treatment of colibacillosis in chickens.


Assuntos
Galinhas , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Doenças das Aves Domésticas/epidemiologia , Animais , China/epidemiologia , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Testes de Sensibilidade Microbiana/veterinária , Doenças das Aves Domésticas/microbiologia , Prevalência
12.
Poult Sci ; 99(2): 763-771, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32036976

RESUMO

Suboptimal animal welfare may affect natural immunity, rendering animals more susceptible to environmentally conditioned diseases, including those requiring antimicrobial treatment, which may promote antimicrobial resistance (AMR) in bacterial populations. Herewith, we tested the hypothesis that conventionally raised turkeys have higher levels of AMR in indicator Escherichia coli bacteria, but lower levels of natural immunity, as compared to turkeys reared under organic conditions. Litter and serum samples were collected from 28 conventional and 4 organic turkey farms: E. coli isolates from litter were tested for resistance to 14 antimicrobials, while 3 parameters of natural immunity (i.e., lysozyme, hemolytic complement levels, and serum bactericidal activity) were assessed in the sera. Resistant E. coli isolates were identified in both conventional and organic farms but generally more frequently in conventional farms. High rates of resistance to ampicillin (96%), tetracycline (95%), streptomycin (82%), sulfamethoxazole (80%), ciprofloxacin (73%), and trimethoprim (71%), as well as high rates of multiresistance, were observed in conventional farms. Organically raised turkeys had significantly higher levels of lysozyme and serum bactericidal activity than conventional turkeys, and these levels were also higher in turkeys housed in farms where AMR frequency was lower. Findings support the hypothesis that conventional farming conditions may affect turkeys' natural immunity, rendering the animals more susceptible to environmentally conditioned diseases requiring antimicrobial treatment, which would in turn promote AMR. Reducing AMR in turkey farming is therefore more likely to be successful when considering animal welfare as an option to reduce the need of antimicrobial use.


Assuntos
Criação de Animais Domésticos/métodos , Farmacorresistência Bacteriana , Infecções por Escherichia coli/veterinária , Imunidade Inata , Perus , Animais , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Feminino , Itália , Masculino , Testes de Sensibilidade Microbiana/veterinária , Agricultura Orgânica
14.
Vet Microbiol ; 241: 108540, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31928695

RESUMO

Urinary tract infections (UTIs), many of which are caused by bacterial pathogens, are some of the most common infections in dogs. To effectively treat UTIs, it is important to identify the predominant bacterial pathogens and their susceptibility to antimicrobial agents. In this study, we collected 326 samples from cases with UTIs or other urinary system diseases at the China Agricultural University Veterinary Teaching Hospital, Beijing, from 2016-2018. In total, 129 non-duplicate bacterial isolates were recovered from 103 clinical samples. The proportion of positive female samples was higher than that of males. The predominant Gram-negative bacteria were Escherichia coli and Klebsiella spp., while Staphylococcus spp. were the predominant Gram-positive bacteria. Broth microdilution-based antimicrobial susceptibility testing showed that 39 % of E. coli and 51.5 % of Staphylococcus spp. isolates were multidrug-resistant. Specifically, E. coli isolates showed high rates of resistance to ampicillin (40.5 %), ceftazidime (59.5 %), and florfenicol (42.9 %), but limited resistance to amikacin (2.38 %), meropenem (7.14 %), and polymyxin E (7.14 %). In comparison, Staphylococcus spp. showed high rates of resistance to erythromycin (60.6 %), trimethoprim-sulfamethoxazole (54.6 %), and penicillin (45. 5 %), but low resistance rates to vancomycin (6.06 %) and nitrofurantoin (6.06 %). Pulsed-field gel electrophoresis (PFGE)-based typing identified 31 PFGE patterns among the 43 E. coli isolates. These results suggested that multiple bacterial strains, many of which are multidrug-resistant, can cause UTIs in dogs. Thus, basic antimicrobial susceptibility tests should be performed to provide guidance for the selection of first-line clinical therapeutics, and to help prevent the occurrence and spread of induced antimicrobial resistance.


Assuntos
Anti-Infecciosos/farmacologia , Doenças do Cão/microbiologia , Farmacorresistência Bacteriana , Infecções Urinárias/veterinária , Animais , Anti-Infecciosos/classificação , Bacteriúria/microbiologia , Bacteriúria/veterinária , Doenças do Cão/tratamento farmacológico , Cães , Eletroforese em Gel de Campo Pulsado/veterinária , Feminino , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana/veterinária , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia
15.
Prev Vet Med ; 175: 104880, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31918357

RESUMO

The rapid expansion of the ornamental aquaculture industry over the past decades has resulted in a concomitant increase in the use of antibiotics to combat infectious diseases. The aim of this study was to assess the possible role of ornamental fish in the translocation of antibiotic resistant bacteria, with possible consequences for aquarium and public health. We assessed the prevalence of bacterial infections and the antibiotic resistance profile of bacteria isolated from 134 ornamental fish imported into northwest Italy during two years of monitoring. Ornamental fish analyzed were imported mainly from Singapore (40%) and Israel (20%), followed by Thailand (13%), Sri Lanka (12%), Czech Republic (7%), Vietnam (5%) and Indonesia (3%). The most commonly imported fish were freshwater species, particularly those belonging to the Poeciliidae family. Bacteriological exam was positive in 68% of the fish examined. The most frequently isolated bacterium was Aeromonas sobria (37%). Bacteria showed resistance against lincomycin, ampicillin, oxytetracycline and tetracycline. Sensitivity was found for florfenicol, chloramphenicol, gentamicin, and trimethoprim/sulfamethoxazole. Odds ratio (OR) values were calculated as a measure of the association between antibiotic resistance of A. sobria and selected factors (country of origin, fish family and fish species), considering Thailand, Poeciliidae and Poecilia reticulata as control cases. Higher values were found for Vietnam (OR 5.6) and Xiphophorus helleri and X. maculatus (OR 3.0 and 3.7 respectively). Our findings underline the need to improve targeted surveillance of antimicrobial resistance and prevent the translocation of resistant or multi-resistant bacterial strains in ornamental fish, especially in fish imported from countries where surveillance is limited or lacking.


Assuntos
Infecções Bacterianas/veterinária , Farmacorresistência Bacteriana , Doenças dos Peixes/epidemiologia , Animais , Antibacterianos/farmacologia , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Doenças dos Peixes/microbiologia , Itália/epidemiologia , Testes de Sensibilidade Microbiana/veterinária , Prevalência
16.
J Anim Sci ; 98(3)2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31950170

RESUMO

Studies suggest a link between added copper (Cu) and co-selection of antimicrobial resistance (AMR) in Enterococcus spp., but data are inconsistent. This study aimed to assess the impact of added Cu, alone or with a feed-grade antimicrobial, on growth performance, transferable Cu resistance gene (tcrB) prevalence, abundance of tcrB in fecal community DNA, and AMR in fecal enterococci in weaned piglets. A total of 320 barrows (DNA 200 × 400, DNA Genetics) weaned at approximately 21 d of age with 7.4 kg (7.4 ±â€…0.06 kg) BW were used in a 28-d study. Piglets were fed a common non-medicated diet for 7 d of acclimation. Treatments were arranged in a 2 × 2 factorial design with main effects of added Cu (0 vs. 200 mg/kg Cu from Cu sulfate) and chlortetracycline (0 vs. 440 mg/kg CTC). Growth performance and fecal samples were obtained on days 0, 14, and 28. There was no evidence (P > 0.05) for Cu and CTC interaction in growth performance. Pigs fed diets with added Cu had increased (P < 0.05) ADG and ADFI from days 0 to 14, with no evidence for differences (P > 0.05) from days 15 to 28 and 0 to 28. Pigs fed diets with CTC had improved (P < 0.01) ADG, ADFI, and G:F from days 0 to 28. Prevalence of tcrB-positive enterococci was not affected by the addition of Cu and/or CTC (P > 0.05). Prevalence of tcrB-positive enterococci was higher on day 14 than other sampling days (P = 0.002). Prevalence of tetracycline resistance gene [tet(M)]-positive enterococci was not affected by treatments or day (P > 0.05). Prevalence of macrolide resistance gene [erm(B)]-positive enterococci had a significant treatment and sampling day interaction (P = 0.021). The abundance of the tcrB gene in feces, quantified by PCR, was not affected by Cu treatment. The median Cu minimum inhibitory concentrations (MIC) of tcrB-negative and -positive isolates were 3 and 20 mM, respectively (P < 0.001). For day 0 and day 28, all Enterococcus isolates were susceptible to gentamicin, kanamycin, streptomycin, daptomycin, and tigecycline, with a majority of isolates resistant to chloramphenicol, erythromycin, lincomycin, linezolid, tetracycline, tylosin tartrate, and Synercid. In conclusion, 200 mg/kg added Cu or 440 mg/kg CTC in nursery diets improved growth performance of nursery pigs. Added Cu, with or without a selection pressure of CTC, did not increase Cu-resistant enterococci and did not co-select resistance to antibiotics.


Assuntos
Clortetraciclina/farmacologia , Cobre/farmacologia , Enterococcus/efeitos dos fármacos , Fezes/microbiologia , Suínos/crescimento & desenvolvimento , Ração Animal/análise , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/farmacologia , Clortetraciclina/administração & dosagem , Cobre/administração & dosagem , Dieta/veterinária , Farmacorresistência Bacteriana/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana/veterinária
17.
Arch Microbiol ; 202(1): 115-125, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31501949

RESUMO

Staphylococcus aureus is part of the normal flora of animals, and represents one of the leading causes of contagious mastitis in dairy herds worldwide. Sixty-seven epidemiologically unrelated S. aureus isolates from nasal and mastitis milk samples of dairy-producing animals (32 cows, 25 sheep, and 10 goats) were characterized by antimicrobial susceptibility testing and spa typing followed by multilocus sequence typing (MLST) on representative isolates and SCCmec-typing on methicillin-resistant S. aureus (MRSA) isolates. The highest resistance was observed to penicillin (64.2%, 43/67), followed by tetracycline (23.9%, 16/67), erythromycin (22.4%, 15/67), and streptomycin (17.9%, 12/67). In general, 18 spa types (including newly identified t16958) and 13 sequence types (STs) belonging to 8 clonal complexes (CCs) were detected. The cow-associated isolates were mainly assigned to CC5 (n = 18, related to t267-ST97, t521-ST352, t527-ST97, t304-ST6, and t084-ST15), followed by CC398 (n = 6, t937-ST291), CC45 (n = 3, t230-ST45), CC88 (n = 2, t2526-ST88), CC22 (n = 2, t3680-ST22), and CC522 (n = 1, t3576-ST522). Small ruminant isolates were mostly clustered into CC522 (n = 29, related to t3576, t1534, t16958, t7308, t7311, t7305 [ST522], t1534-ST2057, and t5428-ST2079). Two isolates from cows with mastitis were found to be MRSA, exhibited a composite profile of t937-ST291-SCCmecIV. No isolates carried the PVL and mecC genes. A significant difference in clonal types of S. aureus isolates from cows in comparison with those from small ruminants was found. This study demonstrated the circulation of diverse clones of S. aureus among dairy animals in Iran, with a different clonal composition between cows and small ruminants. The current study also reports MRSA-related mastitis in dairy cows, emphasizing the need for comprehensive surveillance.


Assuntos
Antibacterianos/farmacologia , Genótipo , Testes de Sensibilidade Microbiana/veterinária , Ruminantes/microbiologia , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/efeitos dos fármacos , Animais , Bovinos , Indústria de Laticínios , Farmacorresistência Bacteriana/efeitos dos fármacos , Feminino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Tipagem de Sequências Multilocus , Ovinos , Infecções Estafilocócicas/microbiologia
18.
Int J Antimicrob Agents ; 55(1): 105806, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31533074

RESUMO

OBJECTIVES: To characterize the colistin-resistant bacterial population in the gut and assess diversity of mcr-1 transmission within a single individual. METHODS: Large numbers of isolates (>100 colonies/chicken cecum sample) were collected from nine randomly selected mcr-1-positive chickens in China and used for comprehensive microbiological, molecular and comparative genomics analyses. RESULTS: Of 1273 colonies, 968 were mcr-1 positive (962 Escherichia coli, two Escherichia fergusonii, two Klebsiella pneumoniae and two Klebsiella quasipneumoniae). One to six colistin-resistant species and three to 10 E. coli pulsed-field gel electrophoresis (PFGE) clusters could be identified from each sample. Whole-genome sequencing (WGS) analysis of the representative E. coli strains revealed three to nine sequence types observed in a single chicken host. The mcr-1 genes are located in either chromosomes or plasmids of different types, including IncI2 (n=30), IncHI2 (n=14), IncX4 (n=4), p0111(n=2) and IncHI1(n=1). Strikingly, in single cecum samples, one to five Inc type plasmids harbouring mcr-1 could be identified. Great diversity was also observed for the same IncI2 plasmid within a single chicken host. In addition, up to eight genetic contexts of the mcr-1 gene occurred within a single chicken. CONCLUSIONS: There is extensive heterogeneity and flexibility of mcr-1 transmission in chicken gut due to bacterial species differences, distant clonal relatedness of isolates, many types and variations of mcr-positive plasmids, and the flexible genetic context of the mcr-1 gene. These compelling findings indicate that the gut is a 'melting pot' for active horizontal transfer of the mcr-1 gene.


Assuntos
Galinhas/microbiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/enzimologia , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/genética , Escherichia coli/enzimologia , Doenças das Aves Domésticas/microbiologia , Animais , Antibacterianos/farmacologia , Ceco/microbiologia , China/epidemiologia , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Eletroforese em Gel de Campo Pulsado/veterinária , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/epidemiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Transferência Genética Horizontal , Testes de Sensibilidade Microbiana/veterinária , Plasmídeos/genética , Doenças das Aves Domésticas/epidemiologia , Sequenciamento Completo do Genoma/veterinária
19.
Br Poult Sci ; 61(2): 122-131, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31774316

RESUMO

1. The increase in microbial resistance, and in particular multiple drug resistance (MDR), is an increasing threat to public health. The uncontrolled use of antibiotics and antibacterial chemotherapeutics in the poultry industry, especially in concentrations too low to cause inhibition, and the occurrence of residues in feed and in the environment play a significant role in the development of resistance among zoonotic food-borne microorganisms.2. Determining the presence and transmission methods of resistance in bacteria is crucial for tracking and preventing antibiotic resistance. Horizontal transfer of genetic elements responsible for drug resistance is considered to be the main mechanism for the spread of antibiotic resistance.3. Of the many well-known genetic elements responsible for horizontal gene transfer, integrons are among the most important factors contributing to multiple drug resistance. The mechanism of bacterial drug resistance acquisition through integrons is one of the essential elements of MDR prevention in animal production.


Assuntos
Integrons , Aves Domésticas , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Proliferação de Células , Galinhas , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Testes de Sensibilidade Microbiana/veterinária
20.
Trop Anim Health Prod ; 52(1): 407-414, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31376059

RESUMO

The aim of this study was to evaluate the phenotypic (in vitro) antimicrobial susceptibility of milk pathogens isolated from subclinical and clinical mastitis in outdoor dairy herds of S. Miguel, Azores. Between January and March 2018, a total of 144 isolates was obtained from dairy cows with mastitis. Escherichia coli (38.9%; n = 56), Streptococcus uberis (20.1%; n = 29), and coagulase-negative staphylococci (17.4%; n = 25) were the major milk pathogens isolated. An in vitro average susceptibility of 52.0% was observed for 13 different antimicrobials (n = 725). According to an analysis of the mean for proportions, the proportions of bacterial isolates presenting in vitro susceptibility to danofloxacin (75.3%; P < 0.001) and to trimethoprim-sulfamethoxazole (25.0%; P < 0.05) were outside of the upper (65.8%) and lower (25.6%) decision lines, respectively. This profile was related to mainly with E. coli and Strep. uberis isolates. Multidrug resistance was observed in 2.1% isolates, namely, in two Strep. uberis strains from the same farm and one Enterococcus sp. strain. In conclusion, varying degrees of in vitro susceptibility of milk pathogens to the tested antimicrobials were observed, suggesting that these environmental bacteria probably play an important role in the spread of antimicrobial resistances in pastures. The use of fluoroquinolones to treat mastitis of dairy cows should be carefully evaluated in order to maintain their suitability for human medicine.


Assuntos
Farmacorresistência Bacteriana , Infecções por Escherichia coli/veterinária , Mastite Bovina/microbiologia , Leite/microbiologia , Infecções Estreptocócicas/veterinária , Animais , Antibacterianos/farmacologia , Açores , Bovinos , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Feminino , Testes de Sensibilidade Microbiana/veterinária , Fenótipo , Infecções Estreptocócicas/microbiologia , Streptococcus/efeitos dos fármacos , Streptococcus/isolamento & purificação
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