犊牛腹泻大肠杆菌的分离鉴定及耐药性分析

为确定引起湘西北地区某肉牛养殖场犊牛腹泻发生的致病菌种类并分析其耐药性,采用常规培养、革兰染色镜检和生化试验等方法对致病菌进行分离鉴定,利用药物纸片琼脂扩散法(Kirby-Bauer)对分离菌进行药敏试验。结果表明,引起犊牛腹泻的主要致病菌为大肠杆菌;临床分离的大肠杆菌对头孢哌酮、头孢唑林、米诺环素、头孢曲松4种抗生素敏感;对头孢呋辛和头孢他啶2种抗生素中度敏感;对头孢氨苄、哌拉西林、红霉素、万古霉素、强力霉素、青霉素、氨苄西林、羧苄西林、麦迪霉素、环丙沙星、链霉素、丁胺卡那霉素、头孢拉定、庆大霉素、卡那霉素、苯唑西林、复方新诺明、诺氟沙星、奥复酸、四环素、多西环素、林可霉素22种抗菌药物产生耐药性。分离出的大肠杆菌对多种抗菌药物产生耐药性,研究结果为养殖场科学诊断和治疗犊牛腹泻提供了有效依据。     

兔金黄色葡萄球菌的分离鉴定和耐药性分析

为了明确洛阳某地区兔场疑似金黄色葡萄球菌感染病例的致病菌及其药物敏感性，本试验无菌采取病兔的病灶进行细菌分离纯化、革兰染色镜检、16S rDNA序列鉴定，并采用药物纸片琼脂扩散法进行分离菌的药敏试验。分离鉴定结果显示，从病兔肺脏、肝脏和脾脏中分离的致病菌为金黄色葡萄球菌。药敏试验结果显示，分离的金黄色葡萄球菌对红霉素、麦迪霉素、卡那霉素、复方新诺明、氨苄西林、丁胺卡那、头孢氨苄、头孢呋辛、呋喃唑酮具有耐药性；对羧苄西林、哌拉西林、诺氟沙星、多黏菌素B、多西环素、庆大霉素、新霉素敏感。结果表明该兔场家兔发病原因为金黄色葡萄球菌感染，且分离菌对多种药物耐药，通过药敏试验结果合理用药可减少细菌耐药性的发生。     

青海省某奶牛场顽固性乳房炎主要病原菌的分离鉴定与耐药性研究

为了明确青海省某奶牛场顽固性乳房炎的病原菌,并制定有效的防控措施,本试验采用细菌分离、16SrDNA序列分析、细菌基因分型等方法对病牛乳样中的病原菌进行分离鉴定,并进行17种药物的敏感性试验。试验从15份乳样中分离到10株金黄色葡萄球菌、1株表皮葡萄球菌和2株化脓隐秘杆菌,其中10株金黄色葡萄球菌均为荚膜多糖5型分离株;所分离金黄色葡萄球菌对青霉素G、红霉素、头孢氨苄和呋喃妥因耐药率分别为100%、90%、10%和10%;表皮葡萄球菌对青霉素G、复方新诺明和甲氧苄氨嘧啶耐药,而对其他14种抗菌药物敏感;化脓隐秘杆菌对四环素和甲氧苄氨嘧啶耐药,对强力霉素和复方新诺明中度敏感,对其他13种抗菌药物敏感。该牛场顽固性乳房炎是多种病原菌混合感染所致,但以荚膜多糖5型金黄色葡萄球菌为主。不同的病原菌的药物敏感性不同,故而治疗困难,建议使用恩诺沙星治疗病牛并加强隐性乳房炎的筛查与防治,病情得到控制。     

金黄色葡萄球菌的耐药性分析

为调查金黄色葡萄球菌的耐药性现状,用世界卫生组织(WTO)推进的Kirby-Bauer法,完成11株金黄色葡萄球菌对林可霉素、头孢氨苄、丁胺卡那霉素、青霉素G、恩诺沙星、庆大霉素、万古霉素、复方新诺明、氨苄青霉素、氟哌酸、红霉素、阿莫西林12种抗菌药的药敏试验,试验按美国临床实验室标准化委员会(NCCLS)1999年版标准进行判定。结果表明:金黄色葡萄球菌对万古霉素100%敏感,对头孢氨苄和丁胺卡那霉素的敏感程度仅次于万古霉素。但是对β-内酰胺类抗生素几乎全部耐药。对林可霉素、恩诺沙星、庆大霉素、复方新诺明、氟哌酸、红霉素的耐药率分别为63.6%、36.4%、9.1%、45.5%、63.6%、81.8%。     

奶牛隐性乳房炎的诊治及主要病原菌的药敏试验

本试验对潍坊某奶牛场的奶样通过Accu Mast乳房炎病原菌快速诊断皿进行细菌分离鉴定,根据药敏试验采用相应药物进行治疗。试验结果表明:在253例奶样中,分离出链球菌属117株,大肠杆菌82株,克雷伯菌42株。链球菌属对头孢氨苄、头孢噻呋、卡那霉素敏感,敏感率分别为82.05%,70.08%,67.52%,对氨苄青霉素耐药;克雷伯菌对头孢噻呋敏感,敏感率为73.81%,对氨苄青霉素和红霉素耐药。根据药敏试验结果,对链球菌属乳头注射头孢氨苄和卡那霉素,对克雷伯菌乳头注射头孢噻呋,凝固酶阴性葡萄球菌感染的乳房炎先对其进行排空乳区法,进而乳头注射头孢氨苄和卡那霉素。其他细菌均采用乳头注孢氨苄和卡那霉素。大肠杆菌感染的乳房炎仅进行排空乳区法,使其自愈。对链球菌属治愈率为91.45%;对克雷伯菌治愈率为40.47%。     

奶牛乳房炎病原菌的分离鉴定及药敏试验

对发生在洛阳地区的牛乳房炎的病原进行了分离鉴定,分离出的病原菌主要有β-溶血性链球菌、葡萄球菌、大肠埃希氏菌、变形杆菌、绿脓杆菌。以试管2倍稀释法对分离出来的主要感染菌链球菌、葡萄球菌、大肠埃希氏菌进行体外抑菌试验．测定了阿莫西林等25种药物对上述3种细菌的最小抑菌浓度（MIC）。其中大肠埃希氏菌对头孢唑啉、庆大霉素、链霉素、乳酸环丙沙星和氧氟沙星、洛美沙星敏感,对氨苄西林、头孢呋辛钠、三甲氧苄啶和新诺明等耐药：葡萄球菌对阿莫西林、头孢他啶、克林霉素、庆大霉素、新诺明、乳酸环丙沙星和氧氟沙星敏感,对氨苄西林钠、头孢唑啉、多西环素、三甲氧苄啶、盐酸洛美沙星等耐药;β-溶血性链球菌对克林霉素、氧氟沙星敏感,对氨苄西林钠耐药．     

常德市某规模化奶牛场奶牛绿脓杆菌的分离鉴定及药物敏感性分析

为了了解常德市某规模化奶牛场奶牛皮肤化脓感染的病原菌及药物敏感情况,试验采用细菌分离培养、染色镜检、生化试验等方法进行分离鉴定,用Kirby-Barer纸片法测定分离菌对20种抗菌药的敏感性。结果表明:从皮肤化脓感染的脓液中分离到4株绿脓杆菌,分离率为44.44%。分离的绿脓杆菌对新霉素、羧苄西林、氧氟沙星、林可霉素、万古霉素、麦迪霉素等6种药物敏感,敏感率为30%;对甲氧嘧啶、氨苄西林、丙氟哌酸、美满霉素、环丙沙星、头孢拉定、丁胺卡那霉素等7种药物中介,中介率为35%;对头孢他啶、哌拉西林、头孢呋新、米若环素、头孢唑啉、多黏霉素B、苯唑西林7种药物产生耐药,耐药率为35%。说明奶牛场奶牛皮肤化脓感染除有其他细菌感染外还有一部分由绿脓杆菌引起,在临床治疗中应引起重视。     

猪大肠杆菌和葡萄球菌的分离鉴定及耐药性分析

对湘西北地区某猪场患病的仔猪的粪便及病变的脾脏、肝脏、淋巴结、肺脏、肾水肿液进行病原菌分离鉴定,并用Kirby-Bauer法测定分离菌株对15种抗菌药的敏感性。结果表明,患病仔猪分离到大肠杆菌和猪葡萄球菌两种细菌。其中大肠杆菌对庆大霉素、头孢呋肟、丁胺卡那霉素、四环素、先锋必素敏感,对氯霉素、氧哌嗪青霉素、先锋五号、头孢曲松钠、新霉素中介,对羧苄青霉素、强力霉素、青霉素、氨苄青霉素、红霉素有较高的耐药性。葡萄球菌对先锋霉素Ⅴ、丁胺卡那霉素敏感,对头孢曲松钠中介,对其他抗生素耐药。其中大肠杆菌对药物敏感率、中介率、耐药率均为33.33%;葡萄球菌的敏感率为13.33%,中介率为6.67%,耐药率为80.00%。     

临床分离病原菌耐药性监测

以头孢硝噻吩纸片对病原菌进行β－内酰胺酶定性测定,应用Ｋｉｒｂｙ－Ｂａｕｅｒ法进行药物敏感性试验,判定药敏结果。对４６５株送检病料分离病原菌,革兰氏阳性占１９％;革兰氏阴性占８１％,以大肠杆菌、沙门氏菌,巴氏杆菌和金黄色葡萄球菌最为常见。耐苯唑西林的凝固酶阴性葡萄球菌占５０％,耐苯唑西林的金黄色葡萄球菌占２６％,总产酶率为７１％。葡萄球菌对多粘菌素,头孢氨苄耐药率较低,革兰氏阴性杆菌对多粘菌素,氟喹诺酮类药物耐药率较低。大肠杆菌对氟喹诺酮类抗菌药物呈较高的耐药率,且与其它抗菌药物存在交叉耐药     

犬脓皮病病原菌的药敏试验

对36例犬脓皮病分离出的103株细菌进行药物敏感性试验。结果表明,88株葡萄球菌对万古霉素(100%)、苯唑西林(94.3%)和氯霉素(88.6%)等敏感率较高;对青霉素(29.5%)、四环素(22.7%)和复方新诺明(18.2%)敏感率较低;24株葡萄球菌对多种抗生素同时耐药。10株微球菌对环丙沙星、左氧氟沙星和恩诺沙星全部敏感,对万古霉素敏感率仅为90%,对红霉素、克林霉素和复方新诺明敏感率均为0。5株棒状杆菌对万古霉素、头孢曲松、恩诺沙星和阿米卡星敏感,对青霉素(20%)、氨苄西林(25%)、苯唑西林(40%)等敏感率较低。     

猪链球菌Ⅱ型四川分离株对抗菌药的敏感性分析

对四川省不同地区链球菌病病死猪体内分离的7株链球菌Ⅱ型进行抗菌药敏感性试验,用链球菌兰氏D群C55914作为对照,比对菌为肺炎链球菌质控菌株ATCC49619.在32种抗菌药中,选择29种药物进行纸片法药敏试验.试验结果表明:7株链球菌耐药谱非常相似,对青霉素、氨苄西林、阿莫西林、奥格门丁、卡那霉素、红霉素、壮观霉素、氯霉素、氟苯尼考、头孢氨苄、头孢拉定、头孢他定、头孢呋辛、头孢曲松、环丙沙星、氧氟沙星、二氟沙星、沙拉沙星、达氟沙星、恩诺沙星、复方新诺明、万古霉素、亚安培南均敏感;对阿米卡星、新霉素、庆大霉素3株敏感,4株中敏;对四环素和多西环素2株中敏,5株耐药;对链霉素1株中敏,6株耐药.用21种药物进行最小抑菌浓度(MIC)测定,结果7株均对青霉素、氨苄西林、卡那霉素、红霉素、头孢他定、头孢呋辛、头孢曲松、头孢噻呋、环丙沙星、达氟沙星、氧氟沙星、二氟沙星、沙拉沙星、恩诺沙星、磺胺六甲氧嘧啶敏感,1株对新霉素和阿米卡星中敏,2株耐药;所有菌株对四环素、土霉素、多西环素、链霉素均耐药.两种方法总体结果一致.     

7味蒙药对大肠杆菌和金黄色葡萄球菌体外抑菌试验研究

为筛选出对金黄色葡萄球菌（Staphylococcus aureus,S. aureus）和大肠杆菌（Escherichia coli,E. coli）具有良好抑菌作用的蒙药,试验采用打孔法测定S. aureus和E. coli对石榴皮、诃子、小白蒿、黄芩、黄芪、苦参、铁线莲7味蒙药敏感程度,微量稀释法测定蒙药的最小抑菌浓度（minimal inhibitory concentration,MIC）,棋盘法测定敏感蒙药对S. aureus和E. coli的协同指数（fractional inhibitory concentration index,FICI）。结果显示：石榴皮、诃子、黄芩3味蒙药对S. aureus的抑菌圈直径为23.30~32.60 mm,MIC为0.98~7.80 mg/mL;石榴皮、诃子、黄芩3味蒙药对E. coli的抑菌圈直径为5.20~12.50 mm,MIC为7.80~31.50 mg/mL;石榴皮与诃子联合用药对S. aureus的FICI为1.00,为相加作用;诃子与黄芩、石榴皮分别联合用药对E. coli的FICI都为0.75,为相加作用。综上所述,石榴皮、诃子、黄芩3味蒙药对S. aureus综合抑菌效果达极度敏感或高度敏感;石榴皮、诃子、黄芩3味蒙药对E. coli综合抑菌效果达极度敏感或高度敏感;在抑制S. aureus的配方中石榴皮、黄芩、诃子可被优先考虑;在抑制E. coli的配方中黄芩、诃子、石榴皮可被优先考虑。     

Antimicrobial drug susceptibility of Staphylococcus intermedius clinical isolates from canine pyoderma

A total of 50 Staphylococcus intermedius strains isolated in France from canine pyodermas in 2002 were investigated for their susceptibility to various antimicrobial drugs. Antimicrobial susceptibility was assessed using a 2-fold serial dilution method in Mueller-Hinton agar, and the minimal inhibitory concentrations (MICs) were determined. About 62% of the 50 strains tested were producers of beta-lactamase and categorized as penicillin-resistant. About 26% demonstrated resistance to sulphonamides, 46% to oxytetracycline, 30% to chloramphenicol, 28% to streptomycin, kanamycin, neomycin or erythromycin, 22% to clindamycin, 6% to doxycycline, 2% to gentamicin, enrofloxacin, marbofloxacin or pradofloxacin. Acquired resistance was not observed to a clavulanic acid-amoxicillin combination, oxacillin, cephalosporins (cephalexin, ceftiofur and cefquinome), trimethoprim, a sulphamethoxazole-trimethoprim combination and florfenicol. About 42% were simultaneously resistant to three or more antimicrobial classes (multiresistance). All isolates with acquired resistance to erythromycin were also resistant to streptomycin and neomycin/kanamycin. About 22% of isolates exhibited cross-resistance between erythromycin and clindamycin and all clindamycin-resistant isolates also exhibited resistance to erythromycin. Resistance to penicillin, oxytetracycline and chloramphenicol was also positively associated with resistance to erythromycin and streptomycin.     

奶牛乳房炎金黄色葡萄球菌的分离鉴定及药敏试验

[目的] 了解泰州市某奶牛场乳房炎中金黄色葡萄球菌（Staphylococcus aureus）感染情况及其对常用药物的敏感性。[方法] 试验选用Baird-Parker培养基分离、生化鉴定、PCR检测等方法,对采集的9份奶牛乳房炎奶样进行分离鉴定和药敏试验。[结果] 共分离到6株葡萄球菌,进一步通过凝固酶试验和16S rDNA测序等方法鉴定其中3株为金黄色葡萄球菌。药敏试验结果显示,3株金黄色葡萄球菌对青霉素G均耐药,2株对四环素耐药,2株对红霉素和苯唑西林表现为中介。[结论] 该次分离的金黄色葡萄球菌主要对青霉素G和四环素耐药,对其他常用抗生素表现为敏感。     

Antimicrobial resistance of Staphylococcus pseudintermedius isolates from healthy dogs and dogs affected with pyoderma in Japan

Staphylococcus pseudintermedius strains were isolated from healthy dogs and dogs with pyoderma in 2000-2002 and 2009. All the isolates from dogs with pyoderma in 1999-2000 and from healthy dogs in 2000-2002 and 2009 were susceptible to cefalexin and/or other cephalosporins and oxacillin. However, 7.1-12.5 and 11.4% of S. pseudintermedius isolates from dogs with pyoderma in 2009 were resistant to cephalosporins and oxacillin, respectively. All S. pseudintermedius isolates from dogs with pyoderma in 1999-2000 and those from healthy dogs in 2000-2002 were susceptible to fluoroquinolones; however, 50% of the S. pseudintermedius strains isolated from dogs with pyoderma in 2009 and 30% of the S. pseudintermedius strains isolated from healthy dogs in 2009 were resistant to fluoroquinolones. Of the 21 oxacillin-resistant S. pseudintermedius (MRSP) isolates, 11 carried SCCmec type V and 10 carried hybrid SCCmec types II-III. Staphylococcus pseudintermedius strains that were resistant to only one of three fluoroquinolones had a mutation in the quinolone resistance determination region of grlA, whereas S. pseudintermedius strains that were resistant to two or more fluoroquinolones had mutations in the quinolone resistance determination regions of both grlA and gyrA.     

In vitro antimicrobial sensitivity of isolates of Yersinia pseudotuberculosis from deer

The in vitro sensitivity of 34 isolates of Yersinia pseudotuberculosis from red deer (Cervus elaphus) was determined by disc diffusion tests using 15 antimicrobial drugs. All isolates were sensitive to ampicillin, chloramphenicol, gentamycin, kanamycin, neomycin, “septrin” (combination of trimethoprim and sulphamethoxazole) streptomycin and tetracycline. Twenty isolates were sensitive to polymyxin B and 14 were resistant. All isolates were resistant to bacitracin, erythromycin, novobiocin and moderately resistant to furazolidone. The responses using sulphafurazole or trimethoprim were difficult to interpret accurately but most isolates were classified as sensitive.     

Antimicrobial resistance and genetic characterization of fluoroquinolone resistance of Pseudomonas aeruginosa isolated from canine infections

Infections with antimicrobial-resistant bacteria are a great challenge in both human and veterinary medicine. The purpose of this study was to determine antimicrobial susceptibility of 106 strains of Pseudomonas aeruginosa isolated from dogs with otitis and pyoderma from 2003 to 2006 in the United States. Three antimicrobial panels, including 6 classes and 32 antimicrobial agents, were used. A wide range of susceptibility patterns were noted with some isolates being resistant to between 8 and 28 (mean 16) of the antimicrobials tested. Among the beta-lactams, all isolates were resistant to ampicillin, cefoxitin, cefpodoxime, cephalothin and cefazolin followed by amoxicillin/clavulanic acid (99%), ceftiofur (97%), ceftriaxone (39%), cefotaxime (26%), and cefotaxime/clavulanic acid (20%), whereas less than 7% of isolates were resistant to ceftazidime/clavulanic acid, ceftazidime, piperacillin/tazobactam or cefepime. Two isolates were resistant to the carbapenems. Among the quinolones and fluoroquinolones, the most isolates were resistant to naladixic acid (96%), followed by orbifloxacin (52%), difloxacin (43%), enrofloxacin (31%), marbofloxacin (27%), gatifloxacin (23%), levofloxacin (21%), and ciprofloxacin (16%). Among the aminoglycosides, the most resistance was seen to kanamycin (90%), followed by streptomycin (69%), gentamicin (7%), and amikacin (3%). Of the remaining antimicrobials 100% of the isolates were resistant to chloramphenicol followed by tetracycline (98%), trimethoprim/sulfamethoxazole (57%), and sulfisoxazole (51%). Point mutations were present in gyrA, gyrB, parC, and/or parE genes among 34 of the 102 naladixic acid-resistant isolates. Two isolates contained class 1 integrons carrying aadA gene conferring streptomycin and spectinomycin resistance. The findings suggest that many antimicrobial agents commonly used in companion animals may not constitute appropriate therapy for canine pseudomonas infections.     

Susceptibility of Pseudomonas pseudomallei isolates of non-human origin to chemotherapeutic agents by the single disc sensitivity method

Single disc sensitivity tests against 42 strains of Pseudomonas pseudomallei isolated from soil, water, sheep, pigs, goats, birds, a horse and a tree kangaroo have shown that a remarkably similar pattern occurs to that obtained in isolates from human cases. Generally, the organisms are sensitive to kanamycin, novobiocin, compound sulphonamides, sulphamethoxazole/trimethoprim and tetracycline and resistant to ampicillin, bacitracin, cloxacillin, colistin, erythromycin, gentamycin, nitrofurantoin, penicillin, polymyxin B, streptomycin and vancomycin. Sensitivity to neomycin was variable.     

牛源金黄色葡萄球菌生物被膜与毒素基因检测及agr分型

旨在对牛源金黄色葡萄球菌（Staphylococcus aureus，S.aureus）的生物被膜、耐药性、毒素基因和agr基因型进行研究，并分析agr基因型与毒素基因之间的相关性。分别用微量滴定板法、药敏纸片法和PCR对S.aureus的生物被膜、耐药性和毒素基因进行检测，用多重PCR对S.aureus进行agr分型。结果表明，336株牛源S.aureus均能形成生物被膜，其中，形成中等（++）和强（+++）生物被膜的S.aureus分别占52.1%和47.9%。药敏试验结果显示，S.aureus对青霉素耐药最为严重，耐药率达91.7%，其次是红霉素、卡那霉素、克林霉素和庆大霉素，耐药率分别为89.6%、72.9%、66.7%和60.4%，而所有S.aureus对呋喃妥因和利奈唑胺均表现为敏感。PCR检测结果显示，黏附素基因fnbA检出率最高，达99.7%，其次是icaD、icaA、clfA和cna，检出率分别为98.2%、89.6%、86.0%和56.0%，bap基因检出率最低，为14.6%。肠毒素基因sea的检出率为26.5%，其次是seb（8.3%）和sec（6.8%），毒素基因tst的检出率占8.3%。分型结果显示，agr Ⅰ型S.aureus是主要的流行菌株，占77.1%，agr Ⅱ、agr Ⅲ和agr Ⅳ型S.aureus流行率分别为14.0%、4.8%和2.1%。统计分析结果表明，agr Ⅰ型S.aureus更具有携带多种毒素基因的潜力，而agr Ⅳ型S.aureus无毒素基因携带潜力。综上表明，牛乳腺炎性S.aureus对常见的抗菌药物耐药严重，毒素基因分布多样，agr Ⅰ型是奶牛乳腺炎性S.aureus主要的基因型，且具有携带多种毒素基因的能力，其潜在威胁应引起重视。