共查询到20条相似文献，搜索用时 0 毫秒
1.
S S Newman A F Roy D G Luther J D Hoskins H U Cox M T Kearney 《American journal of veterinary research》1985,46(1):294-297
A commercial broth microdilution system for testing the antimicrobial susceptibility of gram-positive cocci was compared with the standardized disk agar-diffusion method by testing 254 clinical strains of staphylococci and streptococci using both methods. A total of 2,794 parallel determinations were made with 92.3% complete agreement between the 2 methods; of the discrepancies encountered, 3.0% were minor, 2.5% were major, and 2.1% were very major. The results indicate that the commercial microdilution system may provide a reliable quantitative method for antimicrobial susceptibility testing of clinical isolates from animals. 相似文献
2.
采用微量肉汤稀释法和D-试验法检测64株凝固酶阴性葡萄球菌（CNs）对10种抗菌药物的耐药性,并用PCR方法分别检测头孢西丁耐药菌株和红霉素耐药菌株中mecA基因以及erinA、ermB、ermC和msrA基因的携带情况。结果表明,所有菌株均对万古霉素和甲氧苄啶／磺胺甲恶唑敏感;泰妙菌素为耐药率（65．6％）最高的抗菌药物,其次是红霉素、氧氟沙星和β-内酰胺类药物。28株（43．8％）CNS对青霉素耐药,其中26株对头孢西丁耐药（MRS）并且均携带mecA基因。30株（46．9％）CNS对红霉素耐药,其中24株为MLSB耐药表型,主要由ermB基因介导。总之,兽医临床CNs分离株对常用抗菌药物的耐药性不同,mecA基因和ermB基因的携带分别是兽医临床MRS和MLSB表型产生的主要原因。 相似文献
3.
Antunes NT Tavío MM Assunção P Rosales RS Aquili V de la Fé C Poveda JB 《Veterinary microbiology》2007,119(1):72-75
In vitro susceptibilities of 16 Mycoplasma mycoides subsp. mycoides large colony type field isolates to 15 antimicrobial agents were determined using a broth microdilution method. The most effective antimicrobials were fluoroquinolones, tetracyclines and macrolides, with MIC values under 2 microg/ml. Resistance to nalidixic acid, gentamicin, streptomycin and spectinomycin was observed. 相似文献
4.
5.
Rocksin A Gerlach GF Schwarz S 《Berliner und Münchener tier?rztliche Wochenschrift》2007,120(1-2):42-49
The determination of quantitative data (minimal inhibitory concentrations [MIC values]) using the broth microdilution method is considered the method of choice for in-vitro susceptibility testing of bacterial pathogens. For the inoculation of microtiter plates used in the broth microdilution method, an inoculation density of 5x10(5) CFU/ml has to be achieved according to the CLSI standard. In this study, it was shown that the requested CFU/ml corresponded to an optical density of 0.00027 of a bacterial suspension determined in a spectrophotometer at 625 nm (OD625).The comparison of susceptibility data of clinical isolates determined by agar disk diffusion and, in parallel, by broth microdilution confirmed the comparability of both methods. For most antibiotics the frequency of "very major errors" was below 10%. However, a higher frequency of errors was observed for combinations of antimicrobial agents and bacteria for which no valid breakpoints are available. The comparative testing of cephalothin showed a frequency of"very major errors" of 20.3% for staphylococci and 18.4% for Enterobacteriaceae; for apramycin the frequency of "major errors"was found to be 46.0% for Enterobacteriaceae. The reference strains as recommended in the CLSI Standard M31-S1 should be used for quality assurance. 相似文献
6.
As part of the basic characterization of Ornithobacterium rhinotracheale, the minimal inhibitory concentrations of 10 antimicrobial drugs were determined for reference strains and Mexican isolates by a broth microdilution method. For optimal growth of the organisms, a supplemented brain-heart infusion broth was used. The susceptibility of O. rhinotracheale to amoxicillin, enrofloxacin, and oxytetracycline was variable. However, consistent higher minimal inhibitory concentrations values were obtained for gentamicin, fosfomycin, trimethoprim, sulfamethazine, sulfamerazine, sulfaquinoxaline, and sulfachloropyridazine. Obtained results among Mexican isolates indicate a marked antimicrobial drug resistance trend. 相似文献
7.
Antunes NT Tavío MM Assunção P Rosales RS Poveda C de la Fé C Gil MC Poveda JB 《Veterinary journal (London, England : 1997)》2008,177(3):436-438
In order to determine how widespread antibiotic resistance has become to standard treatments, the in vitro susceptibilities of 28 Mycoplasma agalactiae Spanish field isolates to 16 antimicrobial agents were determined using a broth microdilution method. The most effective antimicrobials based on minimum inhibitory concentration (MIC)90 values were fluoroquinolones, tetracyclines and macrolides. Two strains were tetracycline resistant. Streptomycin, erythromycin and nalidixic acid resistance was observed in all strains. 相似文献
8.
Ryota MATSUYAMA Naotoshi KUNINAGA Tomoya MORIMOTO Tetsuya SHIBANO Akiko SUDO Kazunari SUDO Makoto ASANO Masatsugu SUZUKI Tetsuo ASAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1179-1181
Plesiomonas shigelloides is a causal agent of gastroenteritis, sepsis
and meningitis in humans. We examined the prevalence of P. shigelloides
among great cormorants (Phalacrocorax carbo hanedae) in Japan and the
antimicrobial susceptibility of isolates. P. shigelloides was isolated
from 33 (47.8%) of 69 fecal samples from great cormorants in 2014. All 33 isolates were
subjected to antimicrobial susceptibility testing using broth microdilution methods, which
showed resistance to ampicillin (31 isolates, 93.9%), tetracycline (two isolates, 6.1%)
and trimethoprim (one isolate, 3.0%). The high prevalence of P.
shigelloides in the great cormorants implicates the possible microbiological
risk to public health. 相似文献
9.
Boerlin P Nicholson V Brash M Slavic D Boyen F Sanei B Butaye P 《Veterinary microbiology》2012,157(3-4):405-411
Enterococcus cecorum is a normal inhabitant of the intestine of birds and other vertebrates. It has recently emerged in Canada and other countries as an important cause of arthritis and osteomyelitis in chickens. The objectives of this study were to assess if this emergence was caused by a particular clone of E. cecorum and to assess the antimicrobial susceptibility of this organism. One hundred and thirteen E. cecorum isolates from infections in Canadian chickens (cases) and from the ceca of control chickens from Canada and Belgium were examined. Isolates were identified using biochemical tests and, for a number of them, identification was confirmed by partial 16S rRNA gene sequencing. Case and control isolates were typed by pulsed-field gel electrophoresis and tested for antimicrobial susceptibility using the broth microdilution method. Cecal isolates from control birds were genetically very diverse but the vast majority of those from cases belonged to a single major clonal lineage. Reduced susceptibility was widespread for tetracycline, bacitracin, and erythromycin. Isolates from cases were generally less susceptible to antimicrobial agents than isolates from control birds. 相似文献
10.
A broth microdilution technique was used to determine the antimicrobial susceptibility of 15 field isolates of Mycoplasma hyorhinis to 10 antimicrobial agents, representative of different classes, and contrasting newer agents to existing ones. For the macrolides, the MIC(90) for tylosin and tilmicosin was 1 and 4 microg/ml, respectively, but was > or = 16 microg/ml for erythromycin. Tetracycline, lincomycin and enrofloxacin each had an MIC(90) of 2 microg/ml. The mycoplasma had similar levels of susceptibility to the aminoglycoside and aminocyclictol classes exhibiting an MIC(90) of 4 microg/ml for gentamicin and 2 microg/ml for spectinomycin. The isolates exhibited high MICs to trimethoprim/sulfamethoxazole with an MIC(90) > or = 16/304 microg/ml. In summary, M. hyorhinis isolates from the US had low MICs against a variety of antimicrobials tested, with the exception of erythromycin and trimethoprim/sulfamethoxazole. 相似文献
11.
García del Blanco N Gutiérrez Martín CB de la Puente Redondo VA Rodríguez Ferri EF 《Research in veterinary science》2004,76(3):195-198
Forty-two recent (1997-1999) Spanish isolates of Francisella tularensis subsp.holarctica were tested in a broth microdilution method for their susceptibilities to 29 antimicrobial agents, including penicillins, cephalosporins, cephamicins, monobactams, penems, aminoglycosides, tetracyclines, macrolides, quinolones, chloramphenicol and fosfomycin. The isolates were resistant to beta-lactam antibiotics and susceptible to chloramphenicol, ciprofloxacin, levofloxacin and norfloxacin. 相似文献
12.
Werckenthin C Luhofer G Böttner A Gangl A Goossens L Hafez HM Hartmann K Kaske M Kehrenberg C Kietzmann M Klarmann D Klein G Krabisch P Kühn T Richter A Schulz B Schwarz S Sigge C Traeder W Waldmann KH Jürgen W;Arbeitsgruppe Antibiotikaresistenz der Deutschen Veterinärmedizinischen;Gesellschaft 《Berliner und Münchener tier?rztliche Wochenschrift》2008,121(1-2):19-26
The determination of minimum inhibitory concentrations by broth microdilution is recommended as method of choice for susceptibility testing of veterinary bacterial pathogens. Accordingly, broth microdilution is used in veterinary routine diagnostic laboratories at a progressive rate. To reduce the costs of susceptibility testing, it is reasonable to develop widely accepted uniform microtitre plate layouts that are produced in large quantities. Such microtitre plate layouts have already been developed and published for the susceptibility testing of pathogens from food-producing animals. However, a microtitre plate layout, especially designed for the testing of bacteria from dogs and cats, should be available, too. The choice of the antimicrobial agents or combinations of antimicrobial agents to be included in a suitable layout should be based on the following criteria: (1) the approval and availability of an antimicrobial agent or combination of agents, (2) known cross-resistances, and (3) availability of approved clinical breakpoints. The latter point is of particular importance for the choice of the numbers of concentrations per antimicrobial agent tested and the range of test concentrations. Taking into account these aspects, a science-based layout proposal for microtitre plates, which are suitable for routine testing of bacteria from dogs and cats, is presented and discussed. 相似文献
13.
Antimicrobial susceptibility of 51 strains of Haemophilus pleuropneumoniae. 总被引：8，自引：3，他引：5 
下载免费PDF全文
下载免费PDF全文 Fifty-one strains of Haemophilus pleuropneumoniae were tested for susceptibility to 27 antimicrobial agents using agar disc diffusion, broth-tube dilution and microdilution methods. There was generally good agreement between the interpretation of the disc diffusion inhibition zones and the actual minimal inhibitory concentrations obtained with the dilution methods. The agreement between the results obtained with the broth-tube dilution method and the microdilution method was very good. Three strains were resistant to penicillin, ampicillin, carbenicillin, methicillin and tetracycline. One of those was also resistant to chloramphenicol. Forty strains were resistant to streptomycin, 23 strains were resistant to novobiocin and seven were resistant to triple sulfa. It is thus necessary to consider resistance development against antimicrobial agents chosen for the treatment of pleuro-pneumonia in pigs caused by Haemophilus pleuropneumoniae. 相似文献
14.
Immunofluorescence and flow cytometric methods were examined to detect and distinguish Mycoplasma gallisepticum and M. synoviae. The procedure employed 24-hr broth cultures of each organism, direct immunofluorescence staining with either homologous or heterologous antiserum, and analyses by flow cytometry. The organisms were distinguishable on the basis of fluorescent profiles when stained with the appropriate antiserum. 相似文献
15.
Schlegelova J Rysánek D Sedivá I Babák V 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2001,48(1):21-29
The results of three standard methods (broth dilution, agar dilution, disk diffusion) and an experimental modification of the microdilution method for determination of resistance to ampicillin, cephalotin, cloxacillin, neomycin, novobiocin, penicillin and streptomycin were compared using 151 Staphylococcus aureus isolates obtained from cases of mastitis. The accuracy of the dilution methods was compared by determination of minimum inhibition concentrations (MIC, MIC50, MIC90 and modal MIC) and by assessment of the agreement within the tolerance of +/-1 dilution step in 2-fold dilution series. The results of the dilution methods were further compared with those of the reference disk diffusion method and the strains were classified as sensitive or resistant using the interpretation criteria for human strains. The comparisons indicated that MIC characteristics and the final classification as sensitive or resistant were method-dependent. Resistance to aminoglycoside antibiotics was observed more often when using broth dilution methods, especially when the broth was supplemented with lactose. 相似文献
16.
Charles M. Gieseker Tina C. Crosby Tamara D. Mayer Sonya M. Bodeis Cynthia B. Stine 《Journal of aquatic animal health》2016,28(1):27-38
Flavobacterium columnare and F. psychrophilum are major fish pathogens that cause diseases that may require antimicrobial therapy. Choice of appropriate treatment is dependent upon determining the antimicrobial susceptibility of isolates. Therefore we optimized methods for broth microdilution testing of F. columnare and F. psychrophilum to facilitate standardizing an antimicrobial susceptibility test. We developed adaptations to make reproducible broth inoculums and confirmed the proper incubation time and media composition. We tested the stability of potential quality-control bacteria and compared test results between different operators. Log phase occurred at 48 h for F. columnare and 72–96 h for F. psychrophilum, confirming the test should be incubated at 28°C for approximately 48 h and at 18°C for approximately 96 h, respectively. The most consistent susceptibility results were achieved with plain, 4-g/L, dilute Mueller–Hinton broth supplemented with dilute calcium and magnesium. Supplementing the broth with horse serum did not improve growth. The quality-control strains, Escherichia coli ATCC 25922 and Aeromonas salmonicida subsp. salmonicida ATCC 33658, yielded stable minimal inhibitory concentrations (MIC) against all seven antimicrobials tested after 30 passes at 28°C and 15 passes at 18°C. In comparison tests, most MICs of the isolates agreed 100% within one drug dilution for ampicillin, florfenicol, and oxytetracycline. The agreement was lower with the ormetoprim–sulfdimethoxine combination, but there was at least 75% agreement for all but one isolate. These experiments have provided methods to help standardize antimicrobial susceptibility testing of these nutritionally fastidious aquatic bacteria.
Received June 24, 2015; accepted October 2, 2015. 相似文献
17.
The serological response and protective immunity elicited in the chicken by the pathogenic Ap3AS strain and the moderately pathogenic 80083 strain of Mycoplasma gallisepticum and variants of strain 80083 attenuated by repeated passage in mycoplasma broth were investigated. Strain 80083 elicited a substantial serum antibody response after administration either in drinking water or by conjunctival sac instillation to 7-week-old SPF chickens. No vaccinated chickens developed air sac lesions when challenged by intra-abdominal (IA) injection with the virulent Ap3AS strain. Chickens vaccinated with strain 80083M (50 broth passages) showed only a weak serological response but were substantially protected when challenged 4 weeks after vaccination. Chickens vaccinated with 80083H (100 broth passages) were serologically negative 4 weeks after vaccination and developed severe air sac lesions after challenge. Thirty-seven-week-old hens vaccinated 6 months previously with strain 80083 had high serum antibody levels and were completely protected against IA challenge with the homologous strain. However, 4/6 showed mild air sac lesions when challenged intra-abdominally with strain Ap3AS. Another group showed high M. gallisepticum serum antibody levels 6 months after vaccination with strain Ap3AS but 4/6 and 2/6 showed mild lesions after IA challenge with strains Ap3AS or 80083, respectively. Strains 80083 or 80083M were administered by conjunctival sac instillation to susceptible 11-week-old commercial pullets at the time of fowl pox vaccination. The concurrent use of both vaccines had no apparent adverse effect on the health of the chickens. Similar protection against IA challenge with strain Ap3AS was produced with the M. gallisepticum vaccines whether used alone or in combination with fowl pox. 相似文献
18.
Stoddard RA Atwill ER Conrad PA Byrne BA Jang S Lawrence J McCowan B Gulland FM 《Veterinary microbiology》2009,133(3):264-271
The aim of this study was to determine if antimicrobial drug use increases resistance of commensal gastrointensinal Escherichia coli of wild northern elephant seals (Mirounga angustirostris) treated in rehabilitation, and, if so, identify the risk factors involved. Minimum inhibitory concentration (MIC) levels of twelve antimicrobial drugs were determined for 289 E. coli isolates from 99 seals sampled at admission and 277 isolates obtained at release from rehabilitation using broth microdilution. Prevalence of E. coli antimicrobial resistance, MIC(50), MIC(90), and clustering of MIC values were determined for seals and the data were analyzed using Fisher's exact test, ordinal logistic regression and negative binomial regression. At release from rehabilitation 77.8% of the seals had antimicrobial resistant E. coli compared to 38.4% of the seals at admission. The MIC(90) for amoxicillin-clavulanic acid, chloramphenicol, enrofloxacin, ticarcillin-clavulanic acid, and trimethoprim-saulfamethoxazole were at levels considered to be sensitive at admission but they increased to levels of resistance at release. E. coli were grouped into four clusters by their MIC values, with increasing levels of resistance going from Cluster 1 to 4. A primary risk factor associated with the probability of a seal having E. coli in Clusters 3 and 4 was time in rehabilitation, regardless of whether the animal received treatment with antimicrobial drugs, suggesting nosocomial infection. The results of this study provide evidence that increased levels of hygiene and appropriate use of antimicrobial therapy might be important in the rehabilitation of wild animals to prevent rise in the prevalence of antimicrobial resistant bacteria. 相似文献
19.
The antimicrobial susceptibilities of 76 field isolates of Brachyspira hyodysenteriae from different states of Australia were tested in a newly developed broth dilution procedure. The antimicrobial agents used were tiamulin, valnemulin, tylosin, erythromycin, lincomycin and clindamycin. The results from the broth dilution susceptibility testing of 39 of the isolates were compared with results obtained for the same isolates using the agar dilution method. Amongst the isolates tested by broth dilution, 17 were from three farms and had been collected over a number of years. Their pulsed field gel electrophoresis pattern previously had been determined. The broth dilution technique was simple to use, less labor intensive than agar dilution, and gave clear end points. The results obtained using the two methods generally corresponded well, although in a few cases the MIC obtained by broth dilution were lower than those with agar dilution. For the 76 isolates tested by broth dilution, the MIC(90) (mg/l) was: tiamulin, 1; valnemulin, 0.5; tylosin>256; erythromycin>256; lincomycin, 64 and clindamycin, 16. Only minor differences in susceptibility patterns were found amongst isolates from different Australian states. Over all the isolates, and also amongst the isolates obtained from different years on the three farms, there was no trend for the susceptibility of the isolates to alter with time. 相似文献