天津地区2型猪链球菌的分离鉴定及耐药性分析

为了解天津地区2型猪链球菌的流行及耐药情况,本研究收集该地区部分规模化养猪场疑似猪链球菌病病料317份,通过病原分离培养、染色特性观察、生化试验、PCR扩增等方法进行鉴定,并对分离菌进行致病性及药敏试验。结果从样品中分离鉴定出11株2型猪链球菌。对小鼠的致病力试验结果显示,应用0.5×10~8 CFU/mL的细菌攻击小鼠,11株2型猪链球菌分离株中有6株具有致死性,其中1株致死率较强,5株致死率较弱。药敏试验结果表明,11株分离菌对9种临床常见药物均表现出很强的耐药性,其中对阿米卡星、四环素和强力霉素耐药性最强,耐药率达到100.00%;且所有分离株均呈多重耐药,其中4个分离株为9重耐药,占36.36%(4/11)。本试验结果表明,天津地区存在2型猪链球菌感染情况,且对多种抗菌药均产生了耐药性,应引起养殖户的高度重视,在防制猪链球菌病时,应有针对性地合理、科学、规范用药和交替用药。     

天津地区2型猪链球菌的分离鉴定及耐药性分析

为了解天津地区2型猪链球菌的流行及耐药情况,本研究收集该地区部分规模化养猪场疑似猪链球菌病病料317份,通过病原分离培养、染色特性观察、生化试验、PCR扩增等方法进行鉴定,并对分离菌进行致病性及药敏试验。结果从样品中分离鉴定出11株2型猪链球菌。对小鼠的致病力试验结果显示,应用0.5×10⁸ CFU/mL的细菌攻击小鼠,11株2型猪链球菌分离株中有6株具有致死性,其中1株致死率较强,5株致死率较弱。药敏试验结果表明,11株分离菌对9种临床常见药物均表现出很强的耐药性,其中对阿米卡星、四环素和强力霉素耐药性最强,耐药率达到100.00%;且所有分离株均呈多重耐药,其中4个分离株为9重耐药,占36.36%（4/11）。本试验结果表明,天津地区存在2型猪链球菌感染情况,且对多种抗菌药均产生了耐药性,应引起养殖户的高度重视,在防制猪链球菌病时,应有针对性地合理、科学、规范用药和交替用药。     

湖北省猪2型链球菌的分布及耐药性分析

为了明确湖北省猪2型链球菌的分布,为猪链球菌病的防控提供依据,从湖北武汉等10个地区的29个县(市、区)的48份发病猪样品中分离出猪链球菌34株,并从中鉴定出猪2型链球菌16株,占全部分离链球菌的47.1%,16株猪2型链球菌分布于10个地区的15个县(市、区)。分离菌株的药敏试验结果显示,16株猪2型链球菌对头孢呋辛、头孢曲松、阿莫西林和氨苄西林100%敏感,对卡那霉素、四环素、阿米卡星、庆大霉素和磺胺异~(~口)恶唑全部耐药,16株分离菌株耐药全部在7种以上。     

四川地区猪沙门菌的分离鉴定及其耐药性分析

为了解四川地区规模化养猪群的沙门菌的带菌情况,采用病原菌的形态学观察、生化鉴定、血清学鉴定和PCR鉴定方法对采自四川10个规模化猪场的600份健康猪粪便进行了沙门菌分离鉴定,并对鉴定出27株沙门菌进行了药物敏感性试验和耐药分析。结果表明,来自四川地区的10个健康猪群的沙门菌总检出率为4.5%(27/600);各个市县的沙门菌的分离率介于1.7%~6.7%之间;分离到沙门菌对四环素、复方新诺明以及氟苯尼考的耐药率分别为96.3%、96.3%和92.6%,耐药率大于85%的药物有氨苄西林、奥格门丁、卡那霉素和恩诺沙星,庆大霉素(74.1%)和大观霉素(77.8%)的耐药率也比较严重,头孢噻呋、头孢唑啉、达氟沙星和多黏菌素E是较为敏感的药物。     

牦牛致病性大肠杆菌的分离鉴定及药敏试验

采集川西北草原红原县牧区具有腹泻症状的牦牛新鲜粪样,分离鉴定出致病性大肠杆菌40株;选取10种常用的抗菌药物对分离菌株进行了药敏试验。结果表明,分离菌株对庆大霉素、硫酸新霉素、氟哌酸、土霉素和恩诺沙星高度敏感,敏感率达100%(40/40),多数菌株对氨苄青霉素、链霉素、头孢唑啉耐药,耐药率分别为50%(20/40)、42.5%(15/40)和40%(16/40)。     

常德市郊仔猪沙门菌的分离鉴定及药敏试验

为了对从常德市郊某猪场病死仔猪分离的沙门菌进行分离、鉴定及耐药情况检测,试验用世界卫生组织(WHO)推荐的Kirby-Bauer氏法对分离株进行药敏试验。结果表明:从2例病猪体内分离鉴定出4株沙门菌,分离率为26.7%;分离株对环丙沙星、氟哌酸、复达新3种药物敏感,对先锋五号、氨苄西林、头孢呋肟3种药物中介,对复方新诺明、丁胺卡那、强力霉素、庆大霉素、美满霉素、羧苄青霉素、红霉素、青霉素、四环素9种药物产生了耐药性,其中敏感率为20.00%,中介率为20.00%,耐药率为60.00%。     

南宁某牛场奶牛乳房炎主要致病菌的分离鉴定与药敏试验

南宁某奶牛场乳房炎治疗用药已经出现低效或无效,为了解其主要致病菌的耐药性,随机采集乳样228份进行体细胞数检测,筛选出75份进行细菌分离鉴定及药敏试验,其中检出167株可疑菌株,并通过生化鉴定等确定出金黄色葡萄球菌28株(占16.8%)、无乳链球菌10株、停乳链球菌4株、乳房链球菌2株(占9.6%)、大肠杆菌35株(占21.0%)。结果表明,大肠杆菌分离株对链霉素等已100%耐药,金黄色葡萄球菌对氨苄西林等已100%耐药,链球菌对阿米卡星、红霉素等已100%耐药。其中三类菌对庆大霉素、头孢唑啉、头孢曲松和氧氟沙星都具有较高敏感性。     

苍蝇中产耐NDM型碳青霉烯类肠杆菌的流行情况与耐药性分析

为明确苍蝇对产NDM型碳青霉烯类耐药肠杆菌(NDM-CRE)传播的作用,对2016年9月-2017年9月采集于青岛地区某肉鸡养殖场周边的苍蝇进行NDM-CRE的流行情况与耐药性分析。通过细菌分离,16S rRNA鉴定与bla_(NDM)耐药基因的确认,从120份苍蝇样品中分离出31株碳青霉烯耐药菌株(分离率为25.8%),其中NDM-CRE 16株(分离率为13.3%),分别为大肠杆菌10株(分离率为8.3%)、弗氏柠檬酸杆菌5株(分离率为4.2%)和肺炎克雷伯菌1株(分离率为8.3%)。对16株NDM-CRE进行NDM亚型鉴定,确认10株为bla_(NDM-5),6株为bla_(NDM-9);对其进行16种抗菌药物敏感性测试,结果显示,所有分离株除对替加环素敏感外,对氨苄西林、阿莫西林-克拉维酸钾(2∶1)、美罗培南、头孢唑啉、头孢西丁、头孢噻呋、四环素、土霉素和复方新诺明均耐药;85%以上的分离株对庆大霉素(87.5%)、氟苯尼考(93.8%)、氯霉素(93.8%)和恩诺沙星(87.5%)耐药;46.7%的分离株对氨曲南耐药;18.8%的分离株对多黏菌素E耐药;所有分离株对至少11种抗菌药物耐药,以耐14种抗菌药物菌株最多(n=6)。此外,对分离菌株进行12种耐药基因检测,结果发现,其至少携带5种耐药基因(bla_(NDM),bla_(TEM-1),sul1,sul2,floR),耐药机制较复杂。研究结果表明,养殖场周边的苍蝇可作为NDM耐药基因的重要载体,可能促进了养殖场、环境及相关人群中NDM-CRE的传播,对养殖产业的健康发展和公共卫生安全具有较大的威胁,有必要对其进行消除。     

宁夏地区犊牛腹泻源大肠杆菌的分离鉴定

为了解宁夏地区犊牛腹泻大肠杆菌的耐药情况及血清型分布,采集犊牛腹泻样本35份,进行大肠杆菌的分离鉴定、药敏试验和血清型鉴定。结果显示,共分离鉴定得到26株大肠杆菌,对四环素、阿莫西林100%耐药,对哌拉西林、氨苄西林、头孢唑啉的耐药率大于95%,对阿米卡星较敏感,耐药率为19.23%;最多对20种抗菌药物耐药,占7.69%(2/26)。10株可定型,16株未定型;已定型的10株大肠杆菌分属7个血清型,分别为O2、O9、O20、O26、O36、O44和O64,优势血清型是O20和O26。结果表明,宁夏地区犊牛腹泻大肠杆菌对抗生素的耐药率高,多重耐药普遍,耐药现象严重。     

猪源链球菌的分离鉴定及生物学特性研究

通过生化试验、药敏试验、PCR分型、毒力基因的PCR检测及动物试验对分离的猪源链球菌进行药物敏感性、血清型和分子流行病学初步研究。从不同省份猪链球菌病疑似病例猪的心血、肝、淋巴结、脑和关节液组织分离出97株链球菌,药敏试验结果表明各菌株对13种抗菌素的耐药谱不同,但对先锋霉素V和环丙沙星的耐药率均低于5%。通过对分离菌株进行PCR鉴定和分型,确认26株为猪链球菌,其中1株为1型,16株为2型,4株为7型,没有9型,另5株为其它型。进一步对1型、2型和7型猪链球菌mrp、epf和sly3种毒力基因的分布情况进行了PCR检测。动物试验表明能100%致死小白鼠的猪链球菌基因型均为epf^＋mrp^＋sly^＋2型猪链球菌,1株2型和1株7型猪链球菌均能复制出典型的猪链球菌病例。     

Susceptibility of Bacteroides from swine abscesses to 13 antibiotics

The minimal inhibitory concentrations (MIC) of 129 strains of genus Bacteroides, isolated from abscesses in pigs, for 13 different antimicrobial agents were determined by an agar-dilution method under anaerobic conditions. Clindamycin, the most active antibiotic tested, had a median MIC of 0.8 micrograms/ml. Penicillin G, talampicillin, minocycline, chloramphenicol, and cefoxitin also inhibited all isolates at lower concentrations. Some isolates of B pyogenes were susceptible to gentamicin (MIC, 0.4 micrograms/ml), erythromycin (MIC, 0.8 micrograms/ml), cephalexin (MIC, 0.8 micrograms/ml), and cefoxitin (MIC, 3.2 micrograms/ml). Erythromycin, at a concentration of 3.2 micrograms/ml, was active against 70% of B suis tested, but it was less active against the other Bacteroides species. Some strains tested were resistant to streptomycin and neomycin.     

湖南省猪链球菌的分离鉴定与药敏试验

对来自湖南省不同地区的疑似猪链球菌病病料进行分离鉴定,并对鉴定出来的猪链球菌进行生化试验和药敏试验.结果表明,生化试验除乳糖、甘露醇、山梨醇外,其他差异不大;药敏试验中菌株之间差异较大,大部分菌株呈多重耐药性,其中对磺胺甲噁唑的耐药率达100%,四环素的耐药率为100%～92.3%,对大环内酯类的耐药率为84.6%～69.2%,氨基糖苷类为69.2%～46.2%,头孢菌素类为69.2%～30.8%,对青霉素类药物的耐药率最低,除阿莫西林较高敏感(84.6%)外,多为中度敏感,对其他药物的敏感率均低于50%.说明湖南省猪链球菌耐药率普遍较高,养殖场应予以高度重视.     

2017-2021年上海市动物源粪肠球菌、屎肠球菌耐药性情况变迁分析

为了解上海地区动物源粪肠球菌、屎肠球菌对常见抗菌药物的耐药及其最小抑菌浓度(minimal inhibitory concentration,MIC)变迁情况,采用微量肉汤稀释法对近五年采集的粪肠球菌、屎肠球菌进行10种常见抗菌药物敏感性测试。结果表明,458株粪肠球菌及283株屎肠球菌对头孢西丁、头孢噻呋及氧氟沙星耐药率较高(均高于60%),对青霉素、阿莫西林/克拉维酸及万古霉素的耐药率较低(均低于11%),粪肠球菌耐药率整体高于屎肠球菌,两者对氧氟沙星、头孢噻呋、氟苯尼考、庆大霉素、利奈唑胺、恩诺沙星的耐药率存在较大差异（耐药率差异为15%~44%）。五年间,粪肠球菌对阿莫西林/克拉维酸、氧氟沙星的MIC50及MIC90均呈下降趋势;屎肠球菌对阿莫西林/克拉维酸、头孢西丁及氟苯尼考的MIC50及MIC90均呈下降趋势。研究表明,近年来上海地区动物源粪肠球菌、屎肠球菌的耐药情况有好转趋势,仍需继续加强肠球菌耐药性监测。     

Antimicrobial susceptibility of clinical strains of Streptococcus suis isolated from pigs in Spain

The antimicrobial susceptibility of 151 clinical Streptococcus suis strains isolated from diseased pigs in Spain was determined by a microdilution method. Isolates were mostly susceptible to beta-lactam antimicrobials, aminoglycosides, enrofloxacin, novobiocin and spectinomycin. More than 87% of the S. suis isolates were resistant to tetracyclines, sulphonamides, macrolides and clindamycin. Strains of serotype 9 were significantly more resistant than strains of serotype 2 (P<0.05) to tylosin (94% versus 77%) and clindamycin (94% versus 64%). Eighty-seven percent of the S. suis isolates were resistant to at least four antimicrobials and nine isolates (6%) were resistant to at least six antimicrobials. The most frequently identified multidrug pattern involved resistance against tetracyclines, sulphonamides, macrolides and lincosamides, with 69% of the isolates exhibiting this resistotype. Fifteen out of the 22 strains of serotype 2 (68.2%), and 84 out of the 98 of the strains of serotype 9 (85.7%) exhibited this resistotype, indicating its widespread distribution among the strains of the two most frequently isolated serotypes.     

广西部分地区猪链球菌的分离鉴定及小鼠致病性研究

对来自广西边境地区部分发病猪场及屠宰场的370份猪组织进行细菌分离鉴定,共分离到16株链球菌,对这16株链球菌进行了形态学观察、PCR鉴定及小鼠致病性试验。结果表明,其形态、染色、生化特性均符合猪链球菌的特点,通过GDH鉴定与测序,证实这16株菌株均为猪链球菌,分别命名为GX1~GX16。通过特异性引物PCR分型（35个血清型）,其中有1株为1型,1株为2型,1株为5型,1株为29型,5株为8型,7株未分出型。用这16株猪链球菌对昆明小鼠和BALB/c小鼠进行动物致病性试验,结果发现,菌株GX10对昆明小鼠和BALB/c小鼠致死率均为100%;菌株GX11对BALB/c小鼠致死率为80%;其他菌株对昆明小鼠和BALB/c小鼠均无致病性。菌株GX10、GX11对BALB/c小鼠的LD₅₀分别为4.5×10⁵和3.6×10⁹ CFU。本试验结果表明,广西边境地区存在致病性猪链球菌8型。BALB/c小鼠对猪链球菌的敏感性高于昆明小鼠,更适合作为猪链球菌致病性研究的动物模型。     

上海地区31株2型猪链球菌的分离鉴定及其耐药性分析

猪链球菌病是由猪链球菌引起的一种重要人畜共患病,尤其是猪链球菌2型,不仅对猪的致病性最强,而目可感染特定人群并致死,给人类公共卫生和养猪业带来巨大影响。本研究采集临床症状疑似2型猪链球菌感染猪的全血及内脏器官,通过观察菌落形态及培养特征,筛选出可疑样品,纯化培养并进行PCR鉴定,筛选到31株2型猪链球菌,最后用纸片扩散法对临床分离到的2型猪链球菌菌株测定其耐药性,结果显示对5种药物耐药率分别为：80%（AM）、68%（GM）、84%（CHL）、52%（SXT）、55%（CIP）。试验结果表明分离的31株2型猪源性链球菌,均为多重耐药株,且青霉素类药物的耐药性较为严重,这为临床在治疗2型猪链球菌病提供了合理的指导作用。     

Detection and molecular typing of Streptococcus suis in tonsils from live pigs in France

Streptococcus suis is an important pathogen of swine, causing meningitis, arthritis, polyserositis, septicemia, and sudden death in weaning piglets as well as fattening pigs. Recently, 3 molecular tests have been developed in our laboratory: a multiplex polymerase chain reaction (m-PCR) assay for the detection of S. suis species and serotypes 2 and 1/2, and 2 molecular typing methods, pulsed-field gel electrophoresis and an approach based on PCR amplification of a fragment of rRNA genes, including a part of the 16S and 23S genes and the 16S-23S rDNA intergenic spacer region (ISR), followed by restriction fragment length polymorphism (RFLP) analysis (ISR-RFLP). In the present study, we used these tests to analyze tonsil samples from clinically healthy pigs and to identify individual isolates of S. suis during epidemiologic investigations of 8 related herds with a history of septicemia caused by S. suis serotype 2. Capsular typing showed that 58% of the strains were nontypable. Of the 17 serotypes present, serotype 22 was the most prevalent. In the 7 farms without clinical signs on the day of sampling, we detected S. suis serotype 2 or 1/2, or both, in less than 5% of the pigs by m-PCR or by bacteriologic culture. In the 8th farm, on which 2 pigs had clinical signs of septicemia on the day of sampling, we detected S. suis serotype 2 or 1/2, or both, by m-PCR in the tonsils of 40% of fattening pigs (21 wk old) that lacked symptoms. Molecular typing of the serotype 2 strains showed a common origin of contamination in these herds, given that 1 pattern (C1) was detected in the isolates from 6 of the 8 herds. However, up to 4 patterns were associated with septicemia and sudden death. Several patterns of S. suis serotype 2 can be responsible for disease in the same herd. These molecular tools may be useful for confident studies of the transmission of S. suis, thereby contributing to the control of S. suis infection.     

Isolation,Identification and Pathogenicity on Mice of Streptococcus suis in Pig in Guangxi Border Area

16 strains of Streptococcus were isolated and identified from 370 pig tissues of clinically morbidity farms and slaughter houses in Guangxi border area.Morphological observation, PCR identification and pathogenicity test were carried out. The results showed that the morphology,dyeing,biochemical characteristics were coincidence with the characteristics of Streptococcus suis,confirmed that 16 strains were Streptococcus suis,and named as GX1 to GX16. Further by divided type identification (35 serotypes) by GDH,1 strains was type 1,1 strains was type 2,1 strains was type 5,1 strain was type 29,5 strains were type 8 and 7 strains could not differentiate types. The pathogenicity of 16 strains Streptococcus suis were detected by Kunming mice and BALB/c mice. The results showed that the letal rate of GX10 for Kunming mice and BALB/c mice was 100%;GX11 for BALB/c mice was 80%;Other strains were apathogenicity to the Kunming mice and BALB/c mice. The LD₅₀ of GX10 and GX11 was 4.5×10⁵ and 3.6×10⁹ CFU for BALB/c mice,respectively. The results showed that pathogenic Streptococcus suis type 8 occured in Guangxi border area. The sensitivity of BALB/c mice to Streptococcus suis was higher than Kunming mice, BALB/c mice was more suitable for the pathogenic study of Streptococcus suis.     

30种中草药对耐药性猪链球菌的抑菌试验

为了观察中草药对耐药性猪链球菌的体外抑菌效果,将所选中草药按常规法制备水提取物,用平板打孔法和试管两倍稀释法检测中草药水提取物对耐药性猪链球菌的抑菌作用.结果所选30种中草药中8种对上述病原菌有中度以上抑菌作用.其中以维吾尔草药V抑菌作用最强,其次是柴胡、吴茱萸、维吾尔草药U、诃子和石榴皮.结果表明所选部分中草药中对耐药性猪链球菌有较强的抑菌作用.