黄羽肉种鸡场死胚中鸡白痢沙门菌的分离鉴定及耐药性分析

为了解广东某黄羽肉种鸡场鸡白痢沙门菌的感染及耐药情况,随机采集该场孵化至21日胚龄时的117个死亡胚进行鸡白痢沙门菌分离,通过生化鉴定、PCR、血清分型及rfbS基因序列测定等鉴定鸡白痢沙门菌分离株,并采用琼脂稀释法测定分离株对16种抗菌药物的最小抑菌浓度(MIC)。结果显示:共分离鉴定出18株鸡白痢沙门菌,分离率为15.38%;18个鸡白痢沙门菌分离株对头孢噻肟、头孢吡肟、亚胺培南、多黏菌素B、庆大霉素、阿米卡星、氟苯尼考、链霉素均敏感,而对磺胺异吡恶唑(100%)、萘啶酸(72.2%)、氨苄西林(55.6%)、四环素(44.4%)耐药率较高,且分离株均有多重耐药性。研究表明该黄羽肉种鸡场已受到鸡白痢沙门菌感染的困扰,有必要尽快启动鸡白痢沙门菌防控与净化。     

河南省鸡源沙门菌新近流行株的分离鉴定及其耐药性分析

旨在了解河南省鸡沙门菌临床分离株血清型分布及药物敏感情况。从河南省各地区养鸡场共采集了沙门菌可疑病料617份,按常规方法进行分离,经生化、PCR及血清型鉴定,共分离出98株鸡源沙门菌,其中血清型定型82株,主要为肠炎沙门菌(62.24%)、鸡白痢沙门菌(18.37%)。进一步Kindy-Bauer(KB)法检测分离菌株对22种药物敏感性表明,所有分离菌株对多粘菌素B、阿米卡星、庆大霉素、萘啶酸较为敏感,对阿齐霉素和氨苄西林耐药率在60.00%～70.00%之间,对红霉素和青霉素表现为极高的耐药性,耐药率高达100.00%。三重以上耐药菌株高达96.94%,七耐以上的菌株为56.12%,耐药最多的菌株可耐18种抗生素。由此可见,河南省禽类沙门菌的感染流行主要以肠炎沙门菌和鸡白痢沙门菌为主,多重耐药十分严重,严重影响了禽类沙门菌病的诊治与预防。     

河北省保定地区雏鸡鸡白痢沙门菌的分离鉴定及耐药性检测

为了有效防控雏鸡白痢沙门菌病,试验自保定某蛋种鸡场疑似为鸡沙门菌病雏鸡采取肝脏病料进行细菌的分离培养、生化鉴定、鸡白痢沙门菌多价血清学鉴定及沙门菌inv A基因PCR鉴定,并对分离菌进行致病性检测及对7种抗菌药物的耐药性检测。结果表明,10株分离菌的形态特征、生化特性、血清学鉴定结果符合鸡白痢沙门菌的特征,说明从病死雏鸡组织中分离出的细菌为鸡白痢沙门菌。沙门菌inv A基因PCR扩增出373 bp目的片段,进一步证实分离菌为鸡沙门菌。用分离菌株接种雏鸡,其死亡率高达90%,表明该菌株有很高的致病性。10株分离菌株对阿莫西林和青霉素耐药率达100%,对阿齐霉素的耐药率达90%,而对阿米卡星、头孢唑林和庆大霉素耐药性较弱、对氧氟沙星较为敏感。3耐菌株多重耐药比例为42.86%,4耐菌株多重耐药比例为57.14%,5耐菌株多重耐药比例为71.43%,说明雏鸡沙门菌分离株对所试抗菌药物均表现出不同程度的耐药性,且表现出多重耐药现象。本试验为鸡白痢沙门菌病的防治提供参考。     

2010～2012年苏皖两省鸡白痢沙门菌的分离鉴定及耐药性分析

通过培养特性、生化反应、血清学试验及PCR检测,对2010年10月～2012年6月江苏、安徽两省送检的禽源病料进行鸡白痢沙门菌的分离鉴定,并对分离株进行药敏试验.结果从1 420份样品中分离鉴定出55株鸡白痢沙门菌;药敏试验结果表明,分离株对萘啶酸、羧苄青霉素、链霉素、磺胺异恶唑和氨苄西林等抗菌药物具有较高的耐药性,而对庆大霉素、头孢曲松、氯霉素和卡那霉素具有较强敏感性.上述鸡白痢沙门菌分离株中,有49株(89.09％)为多重耐药菌株,其中以四耐菌株比例最高(25.45％).本研究对于指导临床合理用药及控制鸡白痢沙门菌发生与流行具有重要的现实意义.     

鸡白痢沙门菌对四环素类药物耐药性和耐药基因调查分析

检测分析珠三角地区69株鸡白痢沙门菌对四环素的耐药性及5种四环素耐药基因[tet(A)、tet(B)、tet(C)、tet(M)和tet(X)]在分离株中的分布情况。结果显示,43株(62.7%)鸡白痢沙门菌分离株对四环素产生耐药性,耐药基因tet(A)的检出率为75.4%,未能检测到耐药基因tet(B)、tet(C)、tet(M)和tet(X),表明鸡白痢沙门菌对四环素的耐药机制以tet(A)基因介导的主动外排为主。     

河南地区麻种鸡死胚中沙门菌的分离鉴定与耐药性分析

为了解麻鸡死胚中沙门菌的感染和耐药状况,本研究于2014年9月～2015年8月采集河南省郑州、平顶山、漯河、商丘地区4个父母代麻鸡场孵化场死胚样品,进行沙门菌分离、血清型鉴定,并用纸片法和PCR方法对菌株耐药表型及相关耐药基因进行检测。结果显示,695份死胚样品共分离到263株沙门菌,分离率为37.8%。包括9种血清型:鸡白痢沙门菌203株、爱丁堡沙门菌17株、汤卜逊沙门菌14株、塞罗沙门菌13株、田纳西沙门菌9株、吉姆皮斯Ⅱ沙门菌4株、加瓦尼沙门菌1株、泰米尔纳德沙门菌1株、恩德培Ⅱ沙门菌1株。其中有两个鸡场样品禽副伤寒沙门菌分离率超过鸡白痢沙门菌。263株沙门菌对磺胺异噁唑(69.6%,183/263)、氨苄西林(40.7%,107/263)、四环素(35.7%,94/263)、土霉素(35.4%,93/263)、磺胺甲噁唑/甲氧苄啶(34.2%,90/263)的耐药较严重,且26.2%(69/263)的菌株表现为多重耐药;所有分离株对多粘菌素E、亚胺培南、美罗培南敏感;不同种鸡场来源的沙门菌耐药情况差异较大;用PCR方法共扩增到15种耐药基因,且检出的5类耐药基因与耐药表型的符合率在81.6%以上。本研究结果为制订种鸡群沙门菌病综合防控措施提供了参考。     

鸡白痢沙门菌的耐药性及磺胺类耐药基因的研究

本研究检测分析了珠三角地区鸡白痢沙门菌对磺胺药的耐药性及相关耐药基因,以进一步了解鸡白痢沙门菌对磺胺药耐药性的产生和传播机制。采用微量稀释法检测69株鸡白痢沙门菌分离株对磺胺药的耐药性,PCR检测了磺胺类耐药基因SulⅠ、SulⅡ和SulⅢ在分离株中的分布情况。结果显示,75.4%的受试菌株对磺胺异恶唑产生了耐药性;耐药基因SulⅡ检出率最高(79.7%),其次是耐药基因SulⅠ(33.3%),未能检出耐药基因SulⅢ。提示珠三角地区鸡白痢沙门菌对磺胺药的耐药情况相当严重,磺胺类耐药基因SulⅠ和SulⅡ在磺胺类耐药菌株的产生中起重要作用。     

动物源性沙门菌的血清型、生物被膜形成能力和耐药性分析

本研究旨在探讨动物源性沙门菌的血清型分布、生物被膜形成能力及其耐药性.从不同动物病料中分离细菌,以PCR方法鉴定沙门菌,结合玻片凝集法和16S rRNA序列测定确定沙门菌的血清型和分布,结晶紫染色定量法检测分离株的生物被膜形成能力,药敏试验检测分离菌对常用药物的敏感性.结果共分离鉴定出58株沙门菌,包括鸡白痢沙门菌、鼠伤寒沙门菌、肠炎沙门菌、丙型副伤寒沙门菌、乙型副伤寒沙门菌、都柏林沙门菌和阿哥那沙门菌等7种血清型,其中鸡群以鸡白痢沙门菌感染为主,肠炎沙门菌次之;水禽以鼠伤寒沙门菌感染为主.生物被膜测定结果显示51.72％的沙门菌分离株可形成生物被膜,其中83.33％的鼠伤寒沙门菌可形成生物被膜.20种抗生素(氨基糖苷类、磺胺类、喹诺酮类、林可酰胺类、氯霉素类、青霉素类、四环素类和头孢菌素类)敏感性试验表明所有菌株对林可霉素耐药,51.72％对4种及其以上抗生素耐药,并出现了1株对所有受试抗生素均耐药的鼠伤寒沙门菌.结果表明鸡白痢沙门菌、鼠伤寒沙门菌和肠炎沙门菌是为目前在家禽中分离的优势血清型;同时具有生物被膜形成能力和多重耐药性的沙门菌将对家禽疾病控制和公共卫生带来更大的威胁.     

华中地区鸡源沙门菌分离鉴定及耐药性分析

为了探明华中地区种鸡场沙门菌(Salmonella)的优势血清型和耐药情况,本研究从湖北、河南、湖南等省市22个规模化鸡场采集病鸡、死胚及弱雏组织样品3 724份,通过分离培养、生化试验、PCR鉴定及血清型试验确定分离菌种属及其血清型,并采用Kirby-Bauer法对分离菌株进行了耐药性分析。结果显示,本试验从3 724份病料中共分离鉴定出124株沙门菌,其中79株为D群肠炎沙门菌(63.71%,79/124),34株为D群鸡白痢沙门菌(27.42%,34/124),8株为B群鼠伤寒沙门菌(6.45%,8/124),有3株沙门菌未能确定血清型。O抗原鉴定79株肠炎沙门菌和34株鸡白痢沙门菌为O9,8株鼠伤寒沙门菌为O4。H抗原鉴定79株肠炎沙门菌为Hg,m,8株鼠伤寒沙门菌为Hi。药敏试验结果显示,124株分离菌株对萘啶酸、氨苄青霉素、四环素和多西环素耐药率分别为95.97%(119/124)、91.94%(114/124)、57.26%(71/124)和70.16%(87/124);对复方新诺明和红霉素耐药率分别为25.81%(32/124)和12.10%(15/124);对氯霉素、庆大霉素、头孢噻肟和卡那霉素耐药率分别为6.45%(8/124)、1.61%(2/124)、1.61%(2/124)和0.81%(1/124);对左氧氟沙星、阿米卡星和多黏菌素B完全敏感。99.19%(123/124)的分离株至少对一种药物耐药,87.10%(108/124)的分离株表现多重耐药。本研究为华中地区养鸡场沙门菌的诊断及防控提供了数据支撑。     

鸡白痢沙门菌耐药基因检测及其与药敏性的相关性分析

为探讨鸡白痢沙门菌耐药基因携带情况及其与药敏性的相关性,研究采用PCR方法对已确定耐药谱的207株鸡白痢沙门菌分离株的6类药物的10种耐药基因进行了检测。结果显示:12株(5.80%)未检出耐药基因,11株(5.31%)可携带多达7种耐药基因,携带3种耐药基因的菌株数量最多,占38.16%。10种耐药基因均可检出,tet C基因检出率最高(54.11%),其次为tet A(50.24%)和blaCMY-2(49.76%)。与菌株药敏性总符合率较高的基因依次为cat I(90.82%)、add A1(87.76%)、tet A(86.36%)、blaTEM-1(79.31%),但cat I的耐药符合率及add A1的敏感符合率均为0。blaCMY-2与tet C虽然基因检出率较高,但与药敏性的符合率均较低。研究表明:鸡白痢沙门菌分离株耐药基因携带率较高,但耐药基因与药敏性并不完全相符,耐药基因检测结果可能并不一定能反映分离菌株的实际耐药状况。     

鸡源印第安纳沙门菌多重耐药性分析

采集山东不同地区鸡源沙门菌,根据Kauffmann-White方法测定分离株血清型,采用肉汤微量稀释法测试分离株对16种抗菌药物的敏感性,PCR方法检测10种耐药基因,分析耐药表型和耐药基因之间的关系。结果显示：共鉴定出沙门菌80株,其中印第安纳沙门菌60株。药敏试验证实：60株印第安纳沙门菌对阿莫西林-克拉维酸、头孢唑啉、多黏菌素、氨苄西林、多西环素和甲氧苄啶等16种抗菌药物普遍耐药。88.33%菌株多重耐药分布在12~15耐,未发现3耐以下的菌株。PCR扩增出int1,blaTEM,aac（6’）-Ib-cr,floR,catA1,tetA,strA,cmlA 8种耐药基因。超过90%的菌株携带int1,blaTEM,floR和aac（6’）-Ib-cr耐药基因。上述结果表明,耐药表型及耐药基因的符合呈现相关性。     

Effects of marketing stress on fecal excretion of Salmonella spp in feeder calves

Fecal samples were collected from 200 feeder-calves on farms in Tennessee, after assembly at a Tennessee auction market, and after transport to a Texas feedyard. A final fecal sample was collected from each calf after 30 days of feedyard confinement. The fecal samples were cultured for the presence of Salmonella spp. Salmonella isolates were serotyped and antimicrobial drug-resistance patterns determined. The number of calves fecal culture-positive for Salmonella spp increased from 0 on the Tennessee farms and auction market to 3/200 (1.5%) at entry into the Texas feedyard, and 16/200 (8%) after 30 days of feedyard confinement. Salmonella serotypes isolated and the number of isolates of each serotype were S reading (8), S cerro (4), S newbrunswick (3), S anatum (2), and S typhimurium (copenhagen; 2). All Salmonella isolates were resistant to 5 or more of 13 antimicrobial drugs tested. Salmonella reading isolates were resistant to 10 or 11 of 13 antimicrobial drugs. The results indicated that the calves could have been infected with Salmonella spp prior to or during the course of the study, and that marketing stress as they moved from farm through feedyard may have induced fecal excretion of salmonellae. In addition, the pattern of antimicrobial drug resistance in the Salmonella isolates was broad.     

鸡白痢沙门氏菌病原的分离鉴定及耐药性分析

为鉴定新疆某些地区鸡白痢沙门氏菌主要流行株的流行现状和耐药情况,本研究采用平板凝集试验方法对有发病史的种鸡场进行现场检测,被检的750只鸡中,发现78例疑似鸡白痢沙门氏菌感染,运用沙门氏菌鉴别培养基、组织病理学观察和PCR方法进行确诊,并进行药敏试验。结果显示,疑似的78例鸡白痢沙门氏菌中有69例符合鸡白痢沙门氏菌的生化特性和病理学特点,PCR成功扩增出invA基因,分离率为9.2%,血清型诊断为D1型;其中分离菌对万古霉素和新霉素耐药性最高,耐药率分别为100.0%和81.2%,而对头孢曲松、克拉维酸和多黏菌素的敏感率达60.0%以上。本研究为养殖户和兽医工作者在净化鸡白痢沙门氏菌及临床用药方面提供参考。     

Isolation,Identification and Analysis of Drug Resistance of Salmonella Pullorum

In order to investigate the epidemic situation and drug resistance of major epidemic Salmonella Pullorum in some areas of Xinjiang, 750 chickens with disease history were detected using the methods of plate agglutination, and a total of 78 cases were diagnosed infection with Salmonella Pullorumin by using Salmonella identification medium, histopathological observation, PCR and drug sensitivity test.The results showed that 69 of 78 cases suspect Salmonella Pullorum were isolated, and prove the biochemical characteristics and pathologic characteristics of Salmonella Pullorum, the invA gene was amplified successfully by PCR,the isolation rate was 9.2% and the serotype was diagnosed as D1. The isolates were the most resistant to vancomycin and neomycin, and Salmonella Pullorum resistant rate was 100.0% and 81.2%, respectively. Drug sensitive test results showed that the sensitive rate of the bacteria were more than 60.0% to ceftriaxone,clavulanate and polymyxin. This study provided reference for farmers and veterinary workers, which indicated it could be used for the purification of Salmonella Pullorum and clinical medication.     

食品动物源沙门氏菌质粒介导喹诺酮类耐药基因的检测与分析

为了解食品动物源沙门氏菌质粒介导喹诺酮类耐药性(Plasmid-mediated quinolone resistance,PMQR),采用微量肉汤稀释法和PCR方法,检测了316株食品动物源沙门氏菌对20种抗菌药物的敏感性,以及菌株中PMQR基因的携带率.结果显示:316株沙门氏菌对20种抗菌药物呈不同程度的耐药性,95.57％菌株为多重耐药菌;316株菌中未检出qnrA、qnrC、qnrD、qnrS和qepA基因,7.91％菌株检出qnrB基因,15.19％菌株检出aac(6 ′ )-Ib-cr基因,7.91％菌株检出oqxA基因,8.86％菌株检出oqxB基因,这是首次在沙门氏菌中发现oqxAB基因;98.11％PMQR阳性菌同时携带2种及以上的耐药基因,呈8～17耐的多重耐药性,其中以qnrB和aac(6′)-Ibcr基因型为主;53株PMQR阳性菌分属于5种不同的基因型,耐药表型或耐药基因型不同的菌株却有相同的PFGE谱型.本次检测的316株食品动物源沙门氏菌耐药较为严重;菌株主要携带qnrB、aac(6 ′ )-Ib-cr及oqxAB基因;不同来源菌株存在同一耐药克隆株的流行.     

Antimicrobial resistance of selected Salmonella isolates from food animals and food in Alberta

Salmonella isolates (n = 209) obtained from food animals and foods in Alberta during 1996 through 1999 were tested for sensitivity to 17 antimicrobials. Of the 3553 antimicrobial susceptibility tests on Salmonella isolates, 11.8% were positive for resistance. These isolates were commonly resistant to tetracycline (35.4%), streptomycin (32.5%), sulfamethoxazole (28.7%), ticarcillin (27.3%), and ampicillin (26.8%). Resistance to at least 1 antimicrobial was observed in 112 isolates (53.6%). Salmonella Typhimurium, S. Typhimurium var. Copenhagen, and S. Heidelberg were the most common serovars among isolates resistant to individual antimicrobials and multiple antimicrobials. The most common profile of multiple-antimicrobial resistance was that which included resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, tetracycline, and ticarcillin. The proportions of isolates that were resistant to antimicrobials were greater among bovine isolates of Salmonella than among poultry isolates, and this difference was greater among isolates from veterinary diagnostic sources than among those from monitoring sources.     

贵州省猪源沙门氏菌对β-内酰胺类药耐药性及耐药基因分析

为了解贵州省猪源沙门氏菌对β-内酰胺类抗菌药物耐药性及其耐药基因的流行情况,本试验从贵州省9个地区规模养猪场中分离鉴定130株沙门氏菌,采用微量肉汤稀释法测定其对常用的8种β-内酰胺类抗菌药物的敏感性,并用PCR法对β-内酰胺酶耐药基因进行检测。结果显示,沙门氏菌对常用的β-内酰胺类抗菌药物耐药性十分严重,其中对头孢他啶的耐药率为100%,其次是氨苄西林和阿莫西林,耐药率分别为80.77%和76.15%,耐药率最低的是头孢噻呋和头孢氨苄,均为46.15%。所有菌株均为多重耐药,其中最少为二重,占总数的2.31%,最多为八重,占总数的4.62%,多重耐药主要集中在四至七重,占总数的88.46%。PCR结果显示,SHV耐药基因未检出,TEM、OXA、CTX-M 3种基因检出率分别是85%、75%和46%,细菌的耐药性与相关耐药基因的检出率基本呈正相关。结果表明,猪源沙门氏菌对β-内酰胺类药物具有普遍耐药性,其中头孢他啶尤为严重。TEM、OXA、CTX-M基因是贵州省猪源沙门氏菌主要耐药基因,临床日益严重的耐药现象与耐药基因的普遍存在有很大的关系。     

High prevalence of multiple resistance to antibiotics in Salmonella serovars isolated from a poultry slaughterhouse in Spain

Salmonellosis is a major foodborne infection in Spain, and strains that are resistant to a great variety of antibiotics have become a major public health concern. The aim of this study was to determine the level of antibiotic resistance in 133 Salmonella isolates obtained from a poultry slaughterhouse in Zaragoza (NE Spain). Antimicrobial resistance testing was performed by disk diffusion method using 19 antibiotics. Results were interpreted following the NCCLS criteria. Overall, the highest percentage of resistance was found to the following antimicrobial agents: sulfadiazine (96.2%), neomycin (53.4%), tetracycline (21.8%), and streptomycin (11.3%). All isolates were found to be resistant to one or more of the antibiotics tested. Multiple resistance was observed in 87 strains (65.4%). We found 23 different patterns of resistance in Salmonella Enteritidis. Resistance to sulfadiazine was the most common single resistance. The most frequent patterns of multiresistant strains were neomycin+sulfadiazine and neomycin+tetracycline+sulfadiazine. S. 4,5,12:b: showed the highest percentages of resistance to the tested drugs, with five different resistance patterns found. Ampicillin+chloramphenicol+streptomycin+sulphonamides+tetracycline (ACSSuT) resistance pattern, commonly associated with S. Typhimurium DT 104, was not detected in strains of the same phage type from broilers. The appearance of substantial multiresistance in foodborne Salmonella isolates suggests the need for more prudent use of antibiotics by farmers, veterinarians, and physicians.     

Antimicrobial resistance in Salmonella enterica serovar Dublin isolates from beef and dairy sources

Salmonella enterica serovar Dublin (S. Dublin) is a cattle-adapted Salmonella serovar, so if antimicrobial resistance in S. Dublin arises as a result of antimicrobial use this most likely occurs within the cattle reservoir without impact from antimicrobial use in humans. We tested the antimicrobial resistance of bovine-origin S. Dublin isolates from 1986 through 2004 using a standard disk diffusion method. High proportions of isolates throughout the time period were resistant to one or more antimicrobials, and a marked increase in resistance to ceftazidime occurred between 2000 and 2004. Dairy-origin isolates were more likely to be resistant to several antibiotics than were isolates from beef operations where exposure to antimicrobials is likely to be less frequent. Plasmid analysis of a subset of isolates also supported the hypothesis that antimicrobial resistance traits in the cattle-adapted serovar Dublin were acquired within the bovine host environment.