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1.
从307份鸡盲肠内容物样品中分离到47株空肠弯曲杆菌,并测定这些空肠弯曲杆菌耐药性,结果显示对喹诺酮类药(环丙沙星)耐药性为31.9%;对氨苄青霉素,克林霉素和红霉素耐药性较高,分别达到85.1%、83.0%和83.0%;而对痢特灵和庆大霉素则较为敏感,敏感度分别为85.1%和74.5%。有89.4%的菌株显示多重耐药性。利用MAMAPCR技术,对获得的47株空肠弯曲杆菌进行检测,结果显示对环丙沙星耐药的15株空肠弯曲杆菌均检测出其在gyrA基因257位发生点突变,30株对喹诺酮药物敏感的菌株均未检出。另外2株对环丙沙星耐药的菌株,有1株检测出点突变。 相似文献
2.
为了解鸡源弯曲菌分离株中毒力基因携带情况和耐药现状，探讨毒力基因的存在与耐药性的关系，本试验通过PCR方法对贵州省9个市(州)禽类养殖场分离的96株弯曲菌进行毒力基因检测，采用琼脂稀释法进行药敏试验，通过分类变量的关联性分析，计算关联系数(Cramer’s V)后分析毒力基因与耐药性的相关性。结果显示，在弯曲菌分离株中携带率位于前3名的毒力基因是sodB、cheY、fur(99.0%、96.9%、96.9%),ciaB、virB11的携带率均为0;空肠弯曲菌优势毒力基因谱为flaA-cadF-cheY-cdtA-cdtB-cdtC-fur-katA-sodB,结肠弯曲菌优势毒力基因谱为flaA-cadF-cheY-fur-katA-sodB,结肠弯曲菌毒力基因谱型多于空肠弯曲菌。空肠弯曲菌和结肠弯曲菌分离株耐药率位于前3名的抗菌药均为萘啶酸(88.2%、93.5%)、四环素(85.2%、90.3%)和环丙沙星(73.5%、87.0%);结肠弯曲菌对红霉素、阿奇霉素、链霉素、氯霉素、泰利霉素和克林霉素的耐药水平高于空肠弯曲菌。红霉素与cdtC基因，阿奇霉素与cdtA、cdtB基因，环丙沙... 相似文献
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为了解江苏省鸡源结肠弯曲菌的流行情况和药物敏感性,对江苏省不同规模化养鸡场、农贸市场和超市的鸡泄殖腔样品和鸡肉产品进行结肠弯曲菌的分离及PCR鉴定;采用纸片扩散法测定分离株对17种抗菌药物的敏感性。结果显示,从750份样品(禽肉产品和泄殖腔棉拭子)中分离到81株结肠弯曲菌,分离率为10.8%。耐药性试验结果显示,80%以上菌株对头孢曲松、妥布霉素、诺氟沙星、环丙沙星、林可霉素和甲氧苄氨嘧啶耐药,其中甲氧苄氨嘧啶耐药率达99%,对美罗培南和氟苯尼考保持高度敏感。所有测试菌株出现多重耐药,优势耐药谱为LIN/CRO/CN/T/NOR/CIP。调查结果为结肠弯曲菌防控提供参考依据。 相似文献
4.
采用6种常用抗菌药物对临床分离的38株猪链球菌2型进行敏感性检测,从中选择3株对红霉素和环丙沙星敏感的菌株,采用体外递增药物浓度的方法分别诱导成对红霉素和环丙沙星耐药的菌株,按临床检验标准委员会(CLSI)推荐的方法测定了红霉素和环丙沙星对同一亲本的敏感株和诱导耐药株的体外最小抑菌浓度(MIC),并测定在外排泵抑制剂利血平存在的情况下敏感株和诱导耐药株的MIC变化情况。微量稀释法测定的MIC结果显示:在所选的6种抗生素中,氟苯尼考和氨苄西林对临床分离的38株猪链球菌的作用最好,抑菌率都为100%,红霉素及环丙沙星有一定作用,耐药率分别达39.5%(15/38)和28.9%(11/38),而磺胺间甲氧嘧啶、四环素的抑菌效果最差,耐药率达100%。浓度递增法成功诱导了猪链球菌2型菌株对红霉素和环丙沙星耐药性,其MIC值分别由0.001 8 mg/L上升至128 mg/L。在外排泵抑制剂利血平存在的情况下,抗菌药物对部分猪链球菌2型菌株的MIC值下降。结果提示:逐步增加药物浓度可以诱导猪链球菌2型菌株对红霉素和环丙沙星的耐药性,而且猪链球菌2型菌株耐药性的产生可能与耐药性相关的主动外排机制有关。 相似文献
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6.
河南省鸡源结肠弯曲杆菌的分离鉴定及耐药性分析 《畜牧与饲料科学》2021,42(3):111-114
[目的]掌握河南省鸡源结肠弯曲杆菌的分布和对抗菌药物的耐药情况。[方法]从养殖场抽取鸡泄殖腔拭子460份进行结肠弯曲杆菌分离培养,采用PCR、基质辅助激光解吸电离飞行时间质谱进行鉴定,并通过微量肉汤稀释法对分离菌株进行药物敏感性分析。[结果]共分离结肠弯曲杆菌42株,分离率为9.13%;分离的结肠弯曲杆菌对环丙沙星、萘啶酸、阿奇霉素耐药严重,耐药率分别为95.24%、90.48%、71.43%。[结论]河南省鸡源结肠弯曲杆菌耐药情况较为严重,应规范使用抗菌药物。 相似文献
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猪链球菌2型湖南分离株多重耐药性及相关耐药基因研究 总被引：1，自引：0，他引：1
基因突变和基因转移是细菌耐药性产生和存在的重要内因,检测与抗生素耐药性相关的基因具有重要的意义.试验选取25份猪链球菌2型湖南分离株对16种抗生素进行药敏试验,检测菌株耐药性;选出了23株有红霉素抗性的菌株,用PCR检测其erm(B)基因.结果显示,猪链球菌湖南分离株对红霉素、四环素、万古霉素和克林霉素具有高耐药性,在23株红霉素抗性菌株中有18株存在erm(B)基因,由erm(B)基因产生的红霉素耐药菌株占到其中的78.3%.因此,erm(B)基因是链球菌2型湖南分离株对红霉素耐药的主要抗性决定基因. 相似文献
9.
《中国家禽》2017,(18)
为了解江苏地区鸡源弯曲杆菌的流行和耐药状况,采集养殖场及农贸市场鸡泄殖腔棉拭子样品和超市鸡肉样品进行空肠弯曲杆菌、结肠弯曲杆菌的分离与鉴定,对分离菌株采用纸片扩散法检测其耐药情况。结果显示:泄殖腔棉拭子样品弯曲杆菌总分离率为38.68%(205/530),其中空肠弯曲杆菌和结肠弯曲杆菌阳性率分别为27.36%(145/530)和11.32%(60/530);鸡肉样品中弯曲杆菌总分离率为45.33%(68/150),其中空肠弯曲杆菌和结肠弯曲杆菌阳性率分别为30.00%(45/150)和15.33%(23/150)。所有样品空肠弯曲杆菌分离率极显著高于结肠弯曲杆菌(P0.01),就泄殖腔棉拭子样品而言,养殖场样品弯曲杆菌总分离率显著高于农贸市场样品(P0.05),泄殖腔棉拭子样品与鸡肉样品弯曲杆菌分离率无显著性差异(P0.05)。耐药检测结果显示,弯曲杆菌对9大类27种抗生素耐药率在80%以上的有6种,分别为头孢噻肟、头孢曲松、诺氟沙星、环丙沙星、甲氧苄胺嘧啶和克林霉素,所有菌株表现出多重耐药现象,耐药谱主要集中在12耐、13耐和14耐。研究表明,江苏地区鸡源弯曲杆菌流行普遍,分离菌株存在耐药现象且多重耐药情况较严重。 相似文献
10.
为获得陕西某羊场病羊脓包中的病原菌,以无菌采集的病羊颈部脓汁为材料,进行细菌分离培养,鉴定分离菌株的形态特征、培养特性、生化特性,挑取分离菌株进行协同溶血试验(cAMP)和16SrRNA基因的PCR扩增,并对序列进行分析,NJ法构建系统发育树;用分离菌株分别接种Balb/c小鼠和奶山羊;药敏试验鉴定分离株的耐药性。结果显示,分离菌株的形态特征、培养特性、生化特性与伯杰细菌鉴定手册所述伪结核棒状杆菌特性一致;测序显示分离菌株与GenBank中已收录伪结核棒状杆菌相似性达97%以上;Balb/c小鼠致病性试验和奶山羊动物回归试验表明分离株有强致病性;药敏试验表明分离菌株对红霉素、环丙沙星、克拉霉素、强力霉素、四环素、头孢唑啉、新霉素、氧氟沙星等多种抗生素敏感,对复方新诺明耐药。 相似文献
11.
Antibiotic use in poultry production is a risk factor for promoting the emergence of resistant Escherichia coli. To ascertain differences in different classes of chickens, the resistance profile, some virulence genes and phylogenetic grouping on 251 E. coli isolates from intensive meat (free range and indoor commercial) and free range egg layer chickens collected between December 2008 and June 2009 in South Australia were performed. Among the 251 strains, 102 (40.6%) and 67 (26.7%) were found to be resistant to tetracycline and ampicillin respectively. Resistance was also observed to trimethoprim-sulfamethoxazole (12.4%), streptomycin (10.8%), spectinomycin (9.6%), neomycin (6.0%) and florfenicol (2.0%) but no resistance was found to ceftiofur, ciprofloxacin or gentamicin. Amplification of DNA of the isolates by polymerase chain reaction revealed the presence of genes that code for resistant determinants: tetracycline (tet(A), tet(B) and tet(C)), ampicillin (bla(TEM) and bla(SHV)), trimethoprim (dhfrV and dhfrXIII), sulphonamide (sulI and sulII), neomycin (aph(3)-Ia(aphA1)), and spectinomycin-streptinomycin (aadA2). In addition, 32.3-39.4% of the isolates were found to belong to commensal groups (A and B1) and 11.2-17.1% belonged to the virulent groups (B2 and D). Among the 251 E. coli isolates, 25 (10.0%) carried two or more virulence genes typical of Extraintestinal pathogenic E. coli (ExPEC). Furthermore, 17 of the isolates with multi-resistance were identified to be groups B2 and D. Although no significant difference was observed between isolates from free range and indoor commercial meat chickens (P>0.05), significant differences was observed between the different classes of meat chickens (free range and indoor commercial) and egg layers (P<0.05). While this study assessed the presence of a limited number of virulence genes, our study re emphasises the zoonotic potential of poultry E. coli isolates. 相似文献
12.
Kaesbohrer A Schroeter A Tenhagen BA Alt K Guerra B Appel B 《Zoonoses and public health》2012,59(Z2):158-165
In 2009, 1462 Escherichia coli isolates were collected in a systematic resistance monitoring approach from primary production, slaughterhouses and at retail and evaluated on the basis of epidemiological cut-off values. Besides resistance to antimicrobial classes that have been extensively used for a long time (e.g. sulphonamides and tetracyclines), resistance to (fluoro)quinolones and third-generation cephalosporins was observed. While in the poultry production chain the majority (60%) of isolates from laying hens was susceptible to all antimicrobials tested, most isolates from broilers, chicken meat and turkey meat showed resistance to at least one (85-93%) but frequently even to several antimicrobial classes (73-84%). In the cattle and pig production chain, the share of isolates showing resistance to at least one antimicrobial was lowest (16%) in dairy cows, whereas resistance to at least one antimicrobial ranged between 43% and 73% in veal calves, veal and pork. Resistance rates to ciprofloxacin and nalidixic acid in isolates from broilers were 41.1% and 43.1%, respectively. Likewise, high resistance rates to (fluoro)quinolones were observed in isolates from chicken meat and turkey meat. In contrast, ciprofloxacin resistance was less frequent in E.?coli isolates from the cattle and pig production chain with highest rate in veal calves (13.3%). Highest resistance rates to cephalosporins were observed in broilers and chicken meat, with 5.9% and 6.2% of the isolates showing resistance. In dairy cattle and veal, no isolates with cephalosporin resistance were detected, whereas 3.3% of the isolates from veal calves showed resistance to ceftazidime. Resistance to (fluoro)quinolones and cephalosporins in E.?coli isolates is of special concern because they are critically important antimicrobials in human antimicrobial therapy. The emergence of this resistance warrants increased monitoring. Together with continuous monitoring of antimicrobial usage, management strategies should be regularly assessed and adapted. 相似文献
13.
Parisi A Lanzilotta SG Addante N Normanno G Di Modugno G Dambrosio A Montagna CO 《Veterinary research communications》2007,31(1):113-123
Eleven cattle farms, 8 layer farms, 7 broiler farms and 30 broiler meat samples were investigated in south-eastern Italy throughout
2003 to evaluate the prevalence, the molecular type and antimicrobial resistance of thermophilic Campylobacters. A total of
398 samples were analysed. One Campylobacter isolate for each positive faecal swab and three isolates per positive broiler meat sample were selected for further analysis.
Multiplex PCR was performed for species-level identification and PCR-RFLP of the flagellin A gene for genotyping. Resistance
to 14 antimicrobials was studied in 188 Campylobacter isolates. Prevalence of campylobacters was high both on farms (100%) and in food samples (73%). On 4/11 cattle farms and
on 10/15 poultry farms more than one species was isolated. The presence of more than one genotype was found on 8/11 cattle
farms, on 10/15 poultry farms and in 8/22 Campylobacter-positive food samples. High rates of resistance to quinolone were observed: 9/31 (29%) C. jejuni bovine isolates, 4/22 (18%) C. jejuni poultry isolates, and 14/26 (54%) C. coli poultry isolates. Resistance to sulphamethoxazole-trimethoprim was also observed frequently: 18/26 (69%) of the avian C. coli strains, 25/31 (80%) of the C. jejuni strains isolated from poultry and 15/22 (68%) of those isolated from cattle were resistant. There was a significant difference
between the rate of resistance to macrolides of C. coli and C. jejuni isolated in poultry, which amounted to 23% and 3%, respectively. This study provided data on the prevalence and antimicrobial
resistance of thermophilic campylobacters in south-eastern Italy and confirmed that flaA-typing is an efficient tool to study the epidemiology of Campylobacter strains in short-term investigations. 相似文献
14.
Poultry feed is at the start of the food safety chain in the "farm-to-fork" model, and might serve as a source of antimicrobial resistant bacteria present in poultry meat. Antimicrobial resistance was investigated in 1137 enterococci and 163 Escherichia coli strains recovered from 23 samples of commercial broiler feed and 66 samples of raw feeding materials taken over half a year timespan. Enumeration of enterococci and E. coli were also performed using traditional plating and fluorescent in situ hybridisation methods. Viable enterococci were detected in all feed samples and in 66% of samples of separate feed ingredients, while E. coli was present in 50% and 32% of feed and raw feeding materials, respectively. The median values (50th percentile) for plate and FISH counts for feeds were, respectively, 2.70 log CFU/g and 5.52 log cells/g for enterococci, and 0.15 log CFU/g and 6.00 log cells/g for E. coli. Among enterococci recovered from feed ingredients, resistance to rifampicin, erythromycin, nitrofurantoin, tetracycline, and ciprofloxacin was found in 59.8%, 21.6%, 21.2%, 18.0% and 6.9% of the isolates, respectively. A considerable proportion of the enterococci isolates obtained from broiler feed displayed resistance to tetracycline (69.1%), rifampicin (58.5%), erythromycin (52.9%) and nitrofurantoin (36.2%). Lower percentage of resistance was observed to chloramphenicol (4.6%), ciprofloxacin (3.9%), vancomycin (1.9%) and ampicillin (1.2%). Among E. coli recovered from feed ingredients and poultry feeds, resistance to ampicillin, tetracycline and streptomycin was found in 22.9%, 27.6% and 19.0% and in 22.4%, 41.4% and 17.0% of the isolates, respectively. These data show that feedstuffs and poultry feeds are extensively contaminated by resistant enterococci and, in a lesser extent, by E. coli, thus leading to their introduction in the farm environment. 相似文献
15.
动物源性大肠杆菌药物敏感性检测及耐药性分析 总被引：8，自引：0，他引：8
用2000～2003年自兽医临床分离的393株大肠杆菌,对9种常用抗生素的敏感性进行了检测.依据菌株采集时间、菌株来源对菌株耐药性的变化及耐药性产生之间的相关性进行了较全面的统计分析,并随机选出39株典型的多重耐药菌株观察了对小鼠的致病性.结果显示,393株分离菌对四环素、庆大霉素、氯霉素、氨苄青霉素、利福平、卡那霉素、呋喃妥因、链霉素和环丙沙星的耐药率分别为93.89%, 57.76%,78.63%, 77.86%,92.11%, 47.33%,46.82%, 76.84%,74.81%;按照耐药种类可将分离菌株分为8类,最多耐药9种,最少耐药2种,约80%以上的菌株耐受7种所试药物.猪源大肠杆菌对庆大霉素、氨苄青霉素、卡那霉素的耐药率高,而鸡源大肠杆菌对四环素、氯霉素、链霉素和环丙沙星的耐药率显著高于猪源大肠杆菌.2000年和2003年分离菌株的耐药率相比,氯霉素从67.33%上升到90.58%,氨苄青霉素从71.29%上升到84.81%,链霉素从73.76%上升到80.10%,环丙沙星从61.88%上升到88.48%,庆大霉素却从61.39%下降到53.92%.95%的菌株(37/39)可直接在72 h内致死感染小鼠(2.0×107CFU·鼠-1).5%不能直接致死小鼠的菌株经小鼠体内2～3次传代,可直接致死感染小鼠.试验表明,兽医临床分离菌株普遍存在多重耐药性,并随分离时间、寄主种类等耐药率出现动态变化,耐药类型间具有一定的相关性.耐药菌株对小鼠仍具有很强的致病性,少数菌株致病性出现暂时减弱,但在体内几次传代即可恢复. 相似文献
16.
Thermotolerant Campylobacter spp., in particular Campylobacter jejuni, are among the most frequently identified pathogens, found to be causing human gastrointestinal infections in Europe, with the Czech Republic being no exception. The presented work aimed at assessing results of the first nationwide monitoring of prevalence and antibiotic resistance of Campylobacter spp. in broiler flocks in the Czech Republic, including a comparison of antibiotic resistance of C. jejuni isolates collected from poultry and the human community. The monitoring was carried out in poultry slaughterhouses in 2006 and 2007. From broilers, cloacal swabs were collected and examined. The human isolates of C. jejuni were acquired from rectal swabs in community patients with diarrhoeal diseases. Suspected isolates of both animal and human origin were confirmed by the PCR methods. Antibiotic resistance to selected anti-microbial agents was tested by the microdilution method. In the monitored period, the prevalence of thermotolerant Campylobacter spp. in broilers in the Czech Republic reached almost 50%. In 2006, C. jejuni was detected in 46% and Campylobacter coli in 3% of the tested samples. In 2007, C. jejuni was found in 43% and C. coli in 2% of the samples. The results of anti-microbial susceptibility testing of C. jejuni showed higher resistance in animals when compared with humans. The only exception was tetracycline with higher resistance in isolates of human origin. The highest resistance detected was to quinolone antibiotics. Resistance to oxolinic acid was 77% in animal and 60% in human isolates, to ciprofloxacin 72% in isolates from poultry and 55% in those from humans. In ampicillin, 26% of poultry isolates and 16% of human isolates were resistant. Moreover, 9% of animal isolates demonstrated resistance to streptomycin, undetected in human isolates. In erythromycin, resistance was found in 6% of poultry and 1% of human isolates. 相似文献
17.
Campylobacter is responsible for human bacterial enteritis and poultry meat is recognised as a primary source of infection. In slaughterhouses, cleaning and disinfection procedures are performed daily, and it has been suggested that disinfectant molecules might select for antibiotic resistant strains if shared targets or combined resistance mechanisms were involved. The aim of the study was to investigate if cleaning and disinfection procedures in poultry slaughterhouses select for antibiotic resistance in Campylobacter jejuni and C. coli and to determine the genotypes of isolates collected after cleaning and disinfection. Nine sampling visits were made to four French slaughterhouses. Samples were collected from transport crates and equipment surfaces, before and after cleaning and disinfection. Minimal inhibitory concentrations of the recovered C. jejuni and C. coli isolates to six antibiotics and two disinfectants were measured. The C. jejuni isolates collected from equipment surfaces after cleaning and disinfection were subjected to PCR-RFLP typing. Twenty-five C. jejuni isolates and 1 C. coli were recovered from equipment surfaces after cleaning and disinfection during five visits to three different slaughterhouses. Those isolates did not show an increased resistance to the tested antibiotics compared to isolates collected before cleaning and disinfection. Only one or two genotypes were recovered after cleaning and disinfection during single visits to each slaughterhouse. This observation suggests that such genotypes may be particularly adapted to survive cleaning and disinfection stress. Understanding the survival mechanisms of Campylobacter should facilitate the implementation of better-targeted strategies and reduce the public health burden associated with Campylobacter infection. 相似文献
18.
Jaglic Z Vlkova H Bardon J Michu E Cervinkova D Babak V 《Zoonoses and public health》2012,59(3):202-211
The occurrence of staphylococci and enterococci expressing increased resistance to erythromycin (ERY) and, in particular, to macrolide-lincosamide-streptogramin B (MLS(B) ) antibiotics was investigated in dairy cattle, pigs and turkeys. Three hundred rectal (cloacal) swabs of each animal species were examined. A total of 120 and 71 staphylococci and enterococci, respectively, with increased resistance to ERY were identified. These were most frequent in turkeys (42.3% of positive animals), followed by pigs and dairy cattle (6.7% and 6.0% of positive animals, respectively). Similarly, MLS(B) -resistant isolates colonized predominantly turkeys (29.7% of animals), while their occurrence in pigs and dairy cattle was only sporadic (0.8% of animals). At least one of the erm genes encoding for MLS(B) resistance was found in 56.7% and 69.0% of staphylococci and enterococci, respectively. The erm(C) gene prevailed in staphylococci while the erm(B) gene was predominant in enterococci. Macrolide efflux genes msr(A) and msr(C) were also frequent in staphylococci and enterococci, respectively. Macrolide inactivation gene mph(C) occurred mainly in staphylococci. In staphylococci, methicillin resistance was rarely detected (7.5% of isolates), but resistance to telithromycin (ketolides) was frequent in both staphylococci and enterococci (89.2% and 47.9% of isolates, respectively). This study showed that turkeys represent an important source of ERY (MLS(B) )-resistant cocci. In addition, resistance to ketolides was also frequent. 相似文献
19.
规模化猪场大肠杆菌的耐药性监测及血清流行病学调查 总被引：40，自引：0，他引：40
为了调查猪致病性大肠杆菌的耐药性及流行血清型 ,从湖北、河南、江西、安徽、浙江等省的 33个猪场采集 32 1份仔猪黄、白痢病料进行细菌的分离和生化鉴定 ,结果分离到大肠杆菌 30 2株 ,其中致病性大肠杆菌 2 76株。对 112株致病性大肠杆菌进行了 15种抗生素敏感性试验 ,发现分离菌株对 15种药物均有不同程度的耐药性 :青霉素 G对其完全没有抑制作用 ;先锋霉素 抑制作用最强 (97.3% ) ,其次为呋喃妥因 (78.6 % )、痢特灵 (71.4 % )、环丙沙星(6 8.8% )、诺氟沙星 (6 5 .1% )。 112株菌中 ,有 4 7种耐药谱型 ,多数为 6耐以上的菌株 (80株 ) ,占供试菌株的 71.4 %。应用微量平板凝集试验 ,对分离的 2 76株致病菌进行了血清型鉴定 ,鉴定共有 72种血清型 ,其中优势血清型 10种 ,占能定型分离致病菌株的 5 3.7%。 相似文献
20.
Lukásová J Abraham B Cupáková S 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2004,51(2):77-81
The study was carried out to investigate the incidence of Escherichia coli O157 in raw materials, foodstuffs and the agricultural environment. Of a total of 987 samples examined, 22 strains (2.2%) were identified as E. coli O157 and 10 of them as E. coli O157:H7. Cefixime-Tellurite MacConkey sorbitol agar (CT-SMAC) agar and Biosynth culture medium (BCM) E. coli O157:7 medium were used for the isolation. The virulence factors (stx1, stx2, eae, and ehxA genes) were identified by polymerase chain reaction (PCR). Most strains were isolated from the mechanically deboned poultry meat (nine), minced meat (six) and raw milk (four). One strain was isolated from beef carcass and two strains from waste water. No strains were were found in mass for sausages, refreshment salads, swabs of pork and poultry carcasses and faeces of cattle and pigs. Ten strains from the 22 identified proved to be positive for all factors of virulence. They were isolated from minced meat (four), raw milk (four), waste water (one) and swab from beef carcass (one). Sensitivity to the antimicrobial drugs ampicillin (AMS), ampicillin-sublactam (SAM), tetracycline (TET), ofloxacine (OFL), cefuroxime (CRX), chloramphenicol (CPM), gentamicine (GEN), colistin (COL), cephalozine (CLZ), cefoxitin (CXT), aztreonam (AZT), and sulphamethoxazole + trimethoprim (COT) was tested using the standard dilution technique and disc diffusion test. Minimum inhibitory concentrations (MIC) characteristics (MIC(50), MIC(90), MIC range) and inhibitory zone diameter were determined for each strain. As determined by MICs, the resistance to tested antibiotics in E. coli O157 isolates was found to AMS (90.9%), CLZ (81.8%), CRX (63.6%), CXT (72.7%), CPM (72.7%), TET (81.8%), SAM (59.1%), COT (9.1%), COL (63.61%), AZT (9%) and GEN (4.5%). The similar results were obtained using the disc diffusion method. The differences were found relating to SAM, CXT, CMO and TET. Resistance against one or more antibiotics was found in 95.4% of E. coli O157. Only one strain was susceptible to all tested antibiotics. Most of the strains were resistant to ampicillin and cephalozine. Eight different resistance phenotypes were demonstrated in E. coli O157. 相似文献