猪传染性胸膜肺炎放线杆菌血清2型PCR程序优化及分子鉴定

猪接触性传染性胸膜肺炎（porcine contagious pleuropneumonia,PCP）又称坏死性胸膜肺炎,是由胸膜肺炎放线杆菌引起的一种高度接触传染性、致死性呼吸道传染病。以急性出血性纤维素性肺炎和慢性纤维素性坏死性胸膜炎为主要特征。各种年龄、性别的猪对本病均易感,急性者死亡率高,慢性者常能耐过。猪传染性胸膜肺炎放线杆菌有15个血清型,不同血清型之间没有或仅有较弱的交叉保护作用,这给猪传染性胸膜肺炎放线杆菌的诊断防治和免疫预防带来了很大的困难。因此建立一种快速血清型分子鉴定方法尤为重要。为了快速、简便的建立猪传染性胸膜肺炎放线杆菌血清型分子鉴定的方法,本研究所从临床发病疑似病例猪肺脏和气管中分离到的放线杆菌,首先经过血清型鉴定,确定部分血清型为2型,为了确定血清型鉴定的准确性,在此基础上,采用分子鉴定的方法,对这些菌株进行鉴定,确定分离到的11株菌为猪胸膜肺炎放线杆菌血清2型。这为猪传染性胸膜肺炎放线杆菌血清型分子鉴定及防治提供了理论依据,为今后临床血清型定型提供了一种简便方法。     

鲁西地区猪胸膜肺炎放线杆菌血清型多重PCR研究

本研究建立了鉴定猪胸膜肺炎放线杆菌(APP)血清型的多重PCR方法,并对鲁西地区流行的APP血清型进行了鉴定.根据猪胸膜肺炎放线杆菌的外膜脂蛋白(OmlA)基因设计1对种特异性引物;并且根据血清1型、5型、7型荚膜多(cps)基因设计型特异性引物,建立检测血清1型、5型、7型的PCR方法.运用多重PCR对临床分离鉴定的89株APP进行血清型鉴定,结果表明建立的多重PCR检测方法特异性和敏感性良好,可作为猪传染性胸膜肺炎快速诊断和流行病学调查的重要手段.     

洛阳某猪场猪传染性胸膜肺炎放线杆菌的分离鉴定

为确定洛阳某猪场疑似猪传染性胸膜肺炎的病原种类及其血清型,为其临床科学防疫和合理用药提供参考方案,本试验无菌采集了病猪肺脏等病料,采用病菌培养后形态观察、革兰氏染色、生理生化特性试验、PCR诊断等技术对病原菌进行实验室分离鉴定,通过基因测序和同源性分析方法对其进行确诊,通过动物攻毒试验和药敏试验分析分离菌株的致病性和耐药性,采用5对分型引物对分离菌进行基因分型以确定病原菌血清型。结果显示,分离菌2007菌落形态为光滑、透明、边缘整齐、圆形、隆起的小菌落,革兰氏染色特征为阴性杆菌且呈多型性,具有猪传染性胸膜肺炎放线杆菌（APP）的典型培养特征,且生化结果符合猪传染性胸膜肺炎放线杆菌的生化特性。同源性分析结果显示,分离菌株2007与猪传染性胸膜肺炎放线杆菌菌株FJ848573.1同源性为99.4%,说明分离株2007是猪传染性胸膜肺炎放线杆菌。动物攻毒试验结果显示,分离菌株2007对小鼠有强致病性。药敏试验结果显示,分离株2007对泰妙菌素、氨苄西林和头孢噻呋钠等高敏,对替米考星、红霉素、氟苯尼考等20种抗菌药完全耐药,对34种抗生素的耐药率高达76.5%,具有较强的多重耐药性。分离菌2007基因分型扩增到目的基因片段与血清型5型结果相符。本试验结果为发病猪场提出了解决该病的具体防治措施,并最终获得了良好的效果,为猪传染性胸膜肺炎放线杆菌临床耐药折点的制定提供了一些参考。     

猪传染性胸膜肺炎鉴别诊断和防治方案

<正>猪传染性胸膜肺炎(APP)是由猪胸膜肺炎放线杆菌引起的猪的一种急性、热性传染性呼吸道疾病,临床上以急性出血性纤维素性胸膜肺炎和慢性纤维素性坏死性胸膜肺炎为主要特征。APP目前鉴定的有15种血清型,在我国流行的主要是血清型1型、2型、3型和7型。因为血清型多,各血清型之间很少有交叉免疫保护作用,使疫苗的应用受到了一定的限制,抗生素的使用也存在着诊断不确     

猪接触传染性胸膜肺炎放线杆菌血清3型分子鉴定及药敏试验

为了解猪接触传染性胸膜肺炎放线杆菌(Actinobacillus pleuropneumoniae,APP)的血清型及耐药情况,本研究根据GenBank数据库设计1对引物,特异性的扩增950 bp核苷酸片段,对血清3型APP进行分子鉴定及药敏试验。结果显示,所得PCR产物经过测序,与GenBank已发表的血清3型APP的同源性达99%以上,所分离菌株耐药性较强,大多为多重耐药。通过对血清3型APP进行分子鉴定及药敏试验,为猪传染性胸膜肺炎的鉴定、诊断及防制提供了基础。     

猪胸膜肺炎放线杆菌的分离与鉴定

从山东省泰安市采集的38份具有严重呼吸道症状的病死猪的肺脏、气管和扁桃体进行胸膜肺炎放线杆菌（APP）的分离鉴定,其中14株菌株表现出形态多样性、革兰氏染色阴性等特点,小鼠试验显示有较强的毒力,PCR电泳结果得到了650bp的预期目的片段。系统的生物学鉴定表明,这14株分离菌为胸膜肺炎放线杆菌（Actinobacillus Pleuropneaumoniae,APP）。对确诊的14株APP采用凝集试验进行血清型检测。结果从山东省泰安市分离到14株2个血清型的胸膜肺炎放线杆菌,其中,血清7型8株、血清5型6株,血清7型、5型为绝对优势血清型。     

洛阳某猪场猪传染性胸膜肺炎放线杆菌的分离鉴定

为确定洛阳某猪场疑似猪传染性胸膜肺炎的病原种类及其血清型,为其临床科学防疫和合理用药提供参考方案,本试验无菌采集了病猪肺脏等病料,采用病菌培养后形态观察、革兰氏染色、生理生化特性试验、PCR诊断等技术对病原菌进行实验室分离鉴定,通过基因测序和同源性分析方法对其进行确诊,通过动物攻毒试验和药敏试验分析分离菌株的致病性和耐药性,采用5对分型引物对分离菌进行基因分型以确定病原菌血清型。结果显示,分离菌2007菌落形态为光滑、透明、边缘整齐、圆形、隆起的小菌落,革兰氏染色特征为阴性杆菌且呈多型性,具有猪传染性胸膜肺炎放线杆菌(APP)的典型培养特征,且生化结果符合猪传染性胸膜肺炎放线杆菌的生化特性。同源性分析结果显示,分离菌株2007与猪传染性胸膜肺炎放线杆菌菌株FJ848573.1同源性为99.4%,说明分离株2007是猪传染性胸膜肺炎放线杆菌。动物攻毒试验结果显示,分离菌株2007对小鼠有强致病性。药敏试验结果显示,分离株2007对泰妙菌素、氨苄西林和头孢噻呋钠等高敏,对替米考星、红霉素、氟苯尼考等20种抗菌药完全耐药,对34种抗生素的耐药率高达76.5%,具有较强的多重耐药性。分离菌2007基因分型扩增到目的基因片段与血清型5型结果相符。本试验结果为发病猪场提出了解决该病的具体防治措施,并最终获得了良好的效果,为猪传染性胸膜肺炎放线杆菌临床耐药折点的制定提供了一些参考。     

猪传染性胸膜肺炎放线杆菌参考株抗血清的制备及野毒株血清型鉴定

将猪传染性胸膜肺炎放线杆菌全部12个血清型的国际参考菌株接种于培养基大量培养。回收菌体、甲醛灭活后，加入蜂胶佐剂制成疫苗。分别免疫健康的试验用白兔。获得针对该菌单一血清型的抗血清。虽然不同血清型间有一定的交叉反应，但对同源菌株的菌体抗原的凝集效价最高。分别可达6～8个log2。用该套血清对2003年从山东省各地分离到的猪传染性胸膜肺炎放线杆菌野毒株11株进行了血清型鉴定。分别为3型（2株）、4型（1株）、5型（4株）和7型（4株）。     

胸膜肺炎放线杆菌溶血外毒素研究进展

猪传染性胸膜肺炎是由胸膜肺炎放线杆菌(APP)引起的一种呼吸道传染性疾病.根据荚膜多糖和脂多糖抗原表位不同,将胸膜肺炎放线杆菌分为15个血清型,不同血清型的菌株毒力大小不同,致病性也有强弱之别.研究发现与APP致病性有关的毒力因子包括荚膜多糖、脂多糖、外膜蛋白、转铁结合蛋白、溶血外毒素等,其中溶血外毒素是APP引起猪致病最主要的毒力因子,也是主要的保护性抗原.论文从猪传染性胸膜肺炎溶血外毒素的分子结构、致病机制、免疫原性几个方面对其进行综述,为获得以Apx为抗原制备减毒活疫苗提供参考资料.     

猪胸膜肺炎放线杆菌的分离鉴定及对茶多酚敏感性的研究

猪传染性胸膜肺炎是世界公认的危害养猪业的5个主要传染病之一，该病病原为猪胸膜肺炎放线杆菌（APP）。由于各国流行的血清型不尽相同，各型之间及同一血清型的不同菌株之间的毒力和致病力有差异嘲，几乎无交叉保护；此外，多杀性巴氏杆菌和链球菌都会引起继发性猪急性胸膜肺炎。随着我国养猪业的迅速发展，猪的引进与跨省区运输加速了APP的广泛流行，给该病的诊治带来极大困难。     

Study of antigenic heterogeneity among Actinobacillus pleuropneumoniae serotype 7 strains

Actinobacillus pleuropneumoniae serotype 7 strains were studied for their antigenic heterogeneity using rabbit polyclonal hyperimmune sera against all the known twelve reference strains of A. pleuropneumoniae and a battery of different serological tests such as coagglutination (COA), immunodiffusion (ID), indirect hemagglutination (IHA), counterimmunoelectrophoresis (CIE), rapid dot-ELISA (RDE), serum soft-agar (SSA) and growth agglutination (GA). Reference serotype 7 strain (WF83) showed cross-reactivity with reference serotype 1B strain but not with other serotypes. Field serotype 7 strains showed cross-reactivities with serotypes 1A, 1B, 4, 9, 10, and 11 in COA, ID, and CIE tests, but not in IHA test. Two field strains of serotype 7 (90-3182 and 86-1411) which appeared to be different from the typical serotype 7 strains were selected for further antigenic characterization by SDS-PAGE, Western blot, and Tricine SDS-PAGE assays, and identified as serotypes 1 and 7, respectively. For serotyping atypical strains, it is suggested to use Western blot assay as a confirmatory test to identify serotype-specific capsular and somatic antigens.     

Molecular Identification and Antimicrobial Susceptibility Test of Porcine Contagious Actinobacillus pleuropneumoniae Serotype 3

In order to understand the serotype and drug resistance of porcine contagious Actinobacillus pleuropneumoniae(APP), a pair of primers was designed according to GenBank database to amplify specific 950 bp fragment, and the molecular identification and antimicrobial susceptibility test of APP serotype 3 were investigated.The results showed that the PCR product sequences were more than 99% homology with the APP serotype 3 published in GenBank.The isolated strains were highly resistant and multiple drug resistance.The molecular identification and antimicrobial susceptibility test of APP serotype 3 provided the basis for the identification, diagnosis and prevention of porcine contagious pleuropneumonia.     

In vitro comparison of the activity of various antibiotics and drugs against new Taiwan isolates and standard strains of avian mycoplasma

Twenty-nine antibiotics or drugs were incorporated individually into mycoplasma agar to evaluate their inhibitory activity against avian mycoplasmas: 100 recent Taiwan isolates of 7 serotypes and 10 standard strains of 7 serotypes were tested. All of the standard strains were very sensitive to erythromycin, chlorotetracycline, doxycycline, minocycline, and tetracycline, but the local isolates were highly resistant to these antibiotics. The drugs or antibiotics that possessed an MIC90 of 50 micrograms/ml or less against the local isolates were tiamulin (less than 0.4 micrograms/ml), lincospectin (2.7), josamycin (2.7), lincomycin (3.0), spectinomycin (4.8), tylosin (6.0), kanamycin (6.0), chloramphenicol (6.0), gentamicin (7.5), apramycin (24.5), doxycycline (27.4), minocycline (29.0), spiramycin (30.0), colistin (44.3), leucomycin (45.0), and streptomycin (50.0). The MIC90 of the other antibiotics or drugs was greater than 50 micrograms/ml. None of the isolates or strains were sensitive to nalidixic acid, ronidazole, penicillin, ampicillin, cephalexin, carbadox, or four sulfa drugs at a concentration about 5 times the therapeutic level.     

规模化猪场大肠杆菌的耐药性监测及血清流行病学调查

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%。     

猪胸膜肺炎放线杆菌血清型研究进展

猪传染性胸膜肺炎是当前养猪业的主要呼吸系统传染病之一 ,其病原菌是胸膜肺炎放线杆菌 ,血清型多。准确区分此病原菌的不同血清型是研制预防有效疫苗的前提。根据 NAD依赖性 ,本菌可以分为生物 I型和生物 II型 ;采用传统的血清学方法 ,本菌又分为 1 5个血清型。各种血清学方法仍是现阶段对胸膜肺炎放线杆菌开展血清型鉴定的主要手段 ,但不足之处是存在一定程度的交叉反应以及不能对新分离的病原菌进行分型。采用聚合酶链式反应对不同基因进行扩增 ,根据扩增结果进行血清型鉴定的基因分型方法 ,具有准确和特异的优点 ,并可以克服传统血清学方法的不足 ,已经逐渐成为胸膜肺炎放线杆菌研究中的新的分型方法     

Serological classification and virulence determination of Dichelobacter nodosus isolated from Alberta and British Columbia sheep.

Ovine footrot is a contagious disease of sheep that occurs in temperature climates. It is caused by the strict anaerobe, Dichelobacter nodosus. Benign and virulent organisms are differentiated according to serotype and protease production. This study was conducted to identify the presence of virulent serotypes of D. nodosus in sheep flocks in Alberta and British Columbia. Dichelobacter nodosus was detected in lame sheep from 11 of 15 (73%) flocks in Alberta and in 4 of 5 (80%) British Columbia flocks. It was recovered from 57 of 107 (53%) lame sheep. In Alberta, 4 distinct serotypes were isolated from the 11 positive flocks while in British Columbia a total of 6 different serotypes were isolated. One British Columbia isolate could not be classified into existing serotypes. Of the 19 field strains tested, all but 3 were defined as virulent based upon the rapid rise in protease activity in vitro which was maintained between 3 and 5 d. The knowledge of the serotype and virulence of the D. nodosus isolated from affected animals can assist in the control and prevention of ovine footrot.     

广东省猪传染性胸膜肺炎放线杆菌分离鉴定及耐药表型和耐药基因检测与分析

【目的】了解广东省部分规模化猪场引起猪传染性胸膜肺炎(PCP)的病原菌猪传染性胸膜肺炎放线杆菌(APP)的耐药表型和耐药基因携带情况,并分析比较其相关性,为有效防控该病提供理论依据。【方法】将2019-2021年从广东省不同地区规模化猪场采集的疑似猪传染性胸膜肺炎病死猪病料通过病原分离培养、革兰氏染色、生化试验、PCR扩增等方法进行病原菌分离鉴定和测序分析,随后对分离株进行药敏试验并通过PCR检测其耐药基因,确定其耐药表型和耐药基因的携带率,分析比较两者的一致性。【结果】分离菌需在含有血清和NAD的培养板中生长;革兰氏染色结果显示分离菌为红色,可判定为革兰氏阴性细菌,通过生化试验、PCR结果及测序分析确定分离到20株APP,且没有表现出明显的地域特性。所有菌株均呈现多重耐药且约50%菌株呈8重及以上耐药;其中对四环素类、磺胺类、氯霉素类和大环内酯类药物耐药率较高,分别为77.5%、65.0%、55.0%和48.8%;进一步分析发现,分离菌主要对四环素、磺胺异噁唑、氟苯尼考和林可霉素等抗菌药物耐药,而对头孢唑啉(先锋Ⅴ)和阿奇霉素敏感。23种主要耐药基因中共检测到bla_CMY、aph(2″)-Ⅰb、sul1、sul2、sul3、tetA、tetB、tetM、tetO、tetR和floR这11种耐药基因,携带率分别为85%、85%、50%、60%、75%、30%、100%、85%、100%、70%和80%;未检测到喹诺酮类、大环内酯类和林可胺类相关耐药基因。【结论】从广东省猪群中分离到的APP表现出广泛耐药性,且为多重耐药,耐药基因与耐药表型基本一致,表明耐药基因的携带是细菌对抗菌药物产生耐药的主要原因之一,但也可能存在其他未检测的耐药基因,或存在新的耐药机制。     

Antibiotic resistance pattern among the <Emphasis Type="Italic">Salmonella</Emphasis> isolated from human,animal and meat in India

The present study was conducted to study the antibiotic resistance pattern among nontyphoidal Salmonella isolated from human, animal and meat. A total of 37 Salmonella strains isolated from clinical cases (human and animal) and meat during 2008–2009 belonging to 12 serovars were screened for their antimicrobial resistance pattern using 25 antimicrobial agents falling under 12 different antibiotic classes. All the Salmonella isolates tested showed multiple drug resistance varying from 5.40% to 100% with 16 of the 25 antibiotics tested. None of the isolates were sensitive to erythromycin and metronidazole. Resistance was also observed against clindamycin (94.59%), ampicillin (86.49%), co-trimoxazole (48.65%), colistin (45.94%), nalidixic acid (35.10%), amoxyclave (18.90%), cephalexin, meropenem, tobramycin, nitrofurantoin, tetracycline, amoxicillin (8.10% each), sparfloxacin and streptomycin (5.40% each). Isolates from clinical cases of animals were resistant to as many as 16 antibiotics, whereas isolates from human clinical cases and meat were resistant to 9 and 14 antibiotics, respectively. Overall, 19 resistotypes were recorded. Analysis of multiple antibiotic resistance index (MARI) indicated that clinical isolates from animals had higher MARI (0.25) as compared to isolates from food (0.22) and human (0.21). Among the different serotypes studied for antibiogram, Paratyhi B isolates, showed resistance to three to 13 antibiotics, whereas Typhimurium strains were resistant to four to seven antibiotics. Widespread multidrug resistance among the isolates from human, animal and meat was observed. Some of the uncommon serotypes exhibited higher resistance rate. Considerable changes in the resistance pattern were also noted. An interesting finding was the reemergence of sensitivity to some of the old antibiotics (chloromphenicol, tetracycline).