狐源犬链球菌的分离鉴定

对40余份送检狐狸病料进行细菌分离,采用16S rRNA基因测序和生化试验进行鉴定,并进行细菌耐药性和致病性试验。结果显示:在病料中分离到5株革兰阳性球菌,综合鉴定为犬链球菌;该菌对氨苄西林、氯霉素、环丙沙星等药物敏感,但是对四环素有较强的耐药性;小鼠致病性试验显示该菌犬链球菌QL001的半数致死量为5×10~6cfu,有较强的致病性。研究结果为狐狸链球菌病的防控奠定了基础。     

致蓝狐肺炎的犬链球菌WF1株分离鉴定及药敏试验

为了有效控制蓝狐肺炎的发生,减少蓝狐肺炎的危害,试验采取现场观察、细菌的分离培养和16SrRNA基因序列测定与比对等方法,对潍坊一蓝狐养殖场发生的蓝狐肺炎进行了病原学检查。结果表明:从蓝狐肺部分离到一株犬链球菌,命名为犬链球菌WF1株。说明蓝狐在通风不良、严重热应激,昼夜温差较大等不利因素的刺激下,抵抗力下降,感染了犬链球菌,导致严重肺炎。通过对犬链球菌WF1株药敏试验,发现该菌耐药性较强,但对美罗培南较为敏感。这对于蓝狐肺炎的防控具有一定的指导意义。     

牦牛源副乳房链球菌的分离鉴定及部分生物学特性分析

从青海省某养殖场牦牛肺脏中分离出3株细菌,通过生化试验、16S rDNA序列分析、小鼠致病性试验和药敏试验检测。结果发现,这3株细菌为革兰氏阳性链球菌,与副乳房链球菌(Spu)同源性为99%;分离株在TSA琼脂培养基上呈光滑圆形,半透明的菌落,在血琼脂上呈α溶血;其中Spu-1分离株对小鼠具致病性;药敏试验显示,分离菌株均对链霉素耐药,对红霉素、阿奇霉素、万古霉素和麦迪霉素敏感。研究结果为了解牦牛副乳房链球菌的流行情况提供了新资料。     

牦牛源牛链球菌的分离鉴定及部分生物学特性研究

本研究旨在从腹泻牦牛粪便中分离鉴定牛链球菌,并分析其溶血性、对小鼠的致病性及对抗菌药物的敏感性。将川西北阿坝州45份腹泻牦牛粪便于血平板上划线,37℃、5% CO₂培养24 h分离细菌,经16S rRNA序列扩增测序和系统发育分析鉴定出14株牛链球菌,其中8株巴黎链球菌,6株解没食子酸链球菌巴氏亚种;9株呈α溶血,5株呈β溶血。分离鉴定的牦牛源巴黎链球菌和解没食子酸链球菌巴氏亚种能引起试验小鼠的轻度腹泻;药敏试验结果显示分离菌株对青霉素、头孢噻肟、万古霉素、乙酰螺旋霉素、环丙沙星、利福平、替考拉宁、氨苄西林和庆大霉素共9种抗生素高度敏感,对链霉素、卡那霉素、林可霉素、红霉素、四环素和克林霉素耐药率较高。本研究阐明了牦牛源链球菌的部分生物学特性,为该病的防控奠定了基础。     

林麝源解没食子酸链球菌的分离鉴定及进化分析

采用传统的细菌鉴定方法和分子生物学方法,对四川省某养麝场2只患化脓性疾病林麝病原菌进行生理生化特征和16S rRNA基因序列测定,以小鼠感染试验测试分离菌株的致病性,用K-B纸片扩散法进行药敏试验,并通过构建进化树对分离菌株进行进化分析。该研究分别从2只林麝机体内分离出1株解没食子酸链球菌解没食子酸亚种和1株解没食子酸链球菌马其顿亚种,两分离菌均能够引起小鼠肝脏肿大,且对多类抗生素产生耐药性,进化分析显示,2分离菌处于不同的分支。本试验结果为进一步研究解没食子酸链球菌以及林麝化脓性疾病奠定基础。     

柳州地区罗非鱼无乳链球菌与海豚链球菌分离株药敏性分析

为了解柳州地区罗非鱼链球菌的耐药性情况,本研究对从柳州地区分离得到无乳链球菌和海豚链球菌分离株进行药敏试验。结果显示,无乳链球菌与海豚链球菌之间的药敏结果有较大差异,而同一种细菌的不同菌株对药物的敏感性却较为一致。总体来说,两种菌对青霉素、头孢类药物均具有很高的敏感性,对喹诺酮类药物敏感性不高;无乳链球菌对多粘菌素B、复方新诺明、卡那霉素、磺胺异噁唑4种药物完全耐药,但海豚链球菌却对这些药物呈现不同程度的敏感性。     

引起犬脓皮病皮肤表层细菌分离鉴定

本试验通过采集患犬表层脓液进行细菌分离和纯化培养,之后在麦康凯、伊红美蓝、8.5%NaCl高盐培养基和血琼脂培养基上做鉴别培养;结果23个样本中有葡萄球菌9株、链球菌8株、大肠杆菌5株、其它杂菌1株;对分离得到的细菌做药敏试验,结果表明,金黄色葡萄球菌、链球菌对头孢孟多、庆大霉素、氟哌酸敏感,大肠杆菌对恩诺沙星、头孢孟多、庆大霉素敏感。     

鸭链球菌的分离鉴定及其16S rRNA基因序列分析

从一种表现为脚软、拉稀、死亡增多的新发鸭病病例中分离到1株细菌,命名为GDYJ2011。通过生长特性、染色特性及VITEK-32微生物鉴定系统生化试验鉴定为链球菌,进一步进行16SrRNA基因序列的测定与分析,鉴定为巴氏链球菌。进行人工发病试验,成功的复制出本病,该菌还表现出较强的致病力。结合药敏试验与临床治疗效果,提出了本病的防控措施。     

羊源生物2型犬巴氏杆菌的分离鉴定及药敏试验

为对陕西省某奶山羊场死于呼吸道疾病的羔羊进行病原诊断,无菌采集病死羔羊的肺脏组织进行细菌分离鉴定,并对分离菌株进行致病性试验和药敏试验.结果表明,死亡羔羊肺脏组织分离到的菌株为生物2型犬巴氏杆菌,将该菌株以浓度为1.5×108 CFU/mL的菌液0.2 mL腹腔注射小鼠,小鼠12 h内死亡,对死亡小鼠剖检可见肺脏出血肿...     

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。     

Multiplex PCR-based identification of Streptococcus canis,Streptococcus zooepidemicus and Streptococcus dysgalactiae subspecies from dogs

Streptococcus canis (S. canis), Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) and Streptococcus dysgalactiae subspecies (S. dysgalactiae subspecies) are β-haemolytic Gram positive bacteria infecting animals and humans. S. canis and S. zooepidemicus are considered as two of the major zoonotic species of Streptococcus, while more research is needed on S. dysgalactiae subspecies bacteria. In this work, a multiplex-PCR protocol was tested on strains and clinical samples to detect S. canis, S. dysgalactiae subspecies and S. equi subspecies bacteria in dogs. All strains were correctly identified as S. canis, S. equi subspecies or S. dysgalactiae subspecies by the multiplex-PCR. The main Streptococcus species isolated from symptomatic dogs were confirmed S. canis. The multiplex-PCR protocol described is a rapid, accurate and efficient method for identifying S. canis, S. equi subspecies and S. dysgalactiae subspecies in dogs and could be used for diagnostic purposes and for epidemiological studies.     

Mutagenesis of Streptococcus equi and Streptococcus suis by transposon Tn917

Genetic tools for studying streptococci are much less sophisticated than those that are available for many other bacterial genera. In this paper, we describe the development of a transposon mutagenesis system that we have used to mutate two important veterinary streptococci, Streptococcus equi and Streptococcus suis. The system uses a temperature-sensitive suicide vector to deliver Tn917 via electroporation, transposing Tn917 into the chromosomal DNA of the two streptococci. The transposon insertions can be rescued from the streptococcal chromosomes by plasmid rescue and selection in E. coli, with subsequent insertion site analysis by DNA sequencing. Transposition appeared to have occurred in an essentially random fashion when chromosomal DNA of S. suis and S. equi mutants was analysed by Southern blotting. However, when analysis of 60 S. equi mutants was carried out using the S. equi genome sequence database, 60% of transposon insertions had occurred within a 15 kb region of the genome whereas the other insertions appeared to have occurred essentially randomly. This finding suggests that Southern blot analysis for assessing the randomness of transposon libraries may need to be interpreted with caution. However, this observation notwithstanding, the Tn917 based system described in this paper will facilitate the study of S. suis and S. equi.     

Molecular characterization of Streptococcus agalactiae and Streptococcus uberis isolates from bovine milk

Streptococci are one among the major mastitis pathogens which have a considerable impact on cow health, milk quality, and productivity. The aim of the present study was to investigate the occurrence and virulence characteristics of streptococci from bovine milk and to assess the molecular epidemiology and population structure of the Indian isolates using multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE). Out of a total of 209 bovine composite milk samples screened from four herds (A–D), 30 Streptococcus spp. were isolated from 29 milk samples. Among the 30 isolates, species-specific PCR and partial 16S rRNA gene sequence analysis identified 17 Streptococcus agalactiae arising from herd A and 13 Streptococcus uberis comprising of 5, 7, and 1 isolates from herds B, C, and D respectively. PCR based screening for virulence genes revealed the presence of the cfb and the pavA genes in 17 and 1 S. agalactiae isolates, respectively. Similarly, in S. uberis isolates, cfu gene was present in six isolates from herd C, the pau A/skc gene in all the isolates from herds B, C, and D, whereas the sua gene was present in four isolates from herd B and the only isolate from herd D. On MLST analysis, all the S. agalactiae isolates were found to be of a novel sequence type (ST), ST-483, reported for the first time and is a single locus variant of the predicted subgroup founder ST-310, while the S. uberis isolates were found to be of three novel sequence types, namely ST-439, ST-474, and ST-475, all reported for the first time. ST-474 was a double locus variant of three different STs of global clonal complex ST-143 considered to be associated with clinical and subclinical mastitis, but ST-439 and ST-475 were singletons. Unique sequence types identified for both S. agalactiae and S. uberis were found to be herd specific. On PFGE analysis, identical or closely related restriction patterns for S. agalactiae ST-483 and S. uberis ST-439 in herds A and B respectively, but an unrelated restriction pattern for S. uberis ST-474 and ST-475 isolates from herds D and C respectively, were obtained. This signifies that the isolates of particular ST may exhibit related PFGE patterns suggesting detection of a faster molecular clock by PFGE than MLST. Since all the isolates of both the species belonged to novel sequence types, their epidemiological significance in global context could not be ascertained, however, evidence suggests that they have uniquely evolved in Indian conditions. Further research would be useful for understanding the role of these pathogens in bovine sub-clinical mastitis and implementing effective control strategies in India.     

野生亚洲象解没食子酸链球菌巴氏亚种和解没食子酸链球菌的分离

解没食子酸链球菌巴氏亚种和解没食子酸链球菌是一种人兽共患的细菌传染性疫病。已报道的感染动物有鸽子、火鸡、鹅、鸭,尚未见野生亚洲象感染的报道。2014年11月17日,本研究从患有严重胸膜炎、腹膜炎的野生亚洲象中采集病料,分离到解没食子酸链球菌巴氏亚种和解没食子酸链球菌,特此报道。     

快速鉴定猪链球菌和马链球菌兽疫亚种双重PCR方法的建立

本试验旨在建立一种快速、特异、敏感的双重PCR鉴定猪链球菌和马链球菌兽疫亚种病原检测方法。根据猪链球菌GDH蛋白和马链球菌类 M 蛋白的基因保守区分别设计引物,优化了该双重PCR检测方法的引物浓度及比例,并筛选了其最佳退火温度;用该双重PCR反应体系以其他几株阴性菌株为对照,检测了该反应体系的特异性。以新鲜培养的猪链球菌倍比稀释后进行菌落计数,对该检测方法的敏感性进行了鉴定。M-like和GDH引物的加入量均为1 μL(20 pmol/L),最佳退火温度为52.3℃;该双重PCR反应体系有较高敏感性,检测马链球菌兽疫亚种和猪链球菌的敏感度分别达100和10 CFU;特异性试验结果显示,常见的5种病原菌在该双重PCR体系中无特异性条带出现;临床应用该方法分离鉴定了1株猪链球菌和2株马链球菌兽疫亚种。本试验建立了一种能同时检测猪链球菌和马链球菌兽疫亚种的双重PCR方法,且该方法应用快速、特异且敏感。     

Streptococcus Suis: Past and Present

Staats, J.J., Feder, I., Okwumabua, O. and Chengappa, M.M., 1997. Streptococcus suis: past and present. Veterinary Research Communications, 21 (6), 381-407Steptococcus suis is a Gram-positive, facultatively anaerobic coccus that has been implicated as the cause of a wide range of clinical disease syndromes in swine and other domestic animals. In swine, the disease has spread worldwide but is more prevalent in countries with intensive swine management practices. The disease syndromes caused by S. suis in swine include arthritis, meningitis, pneumonia, septicaemia, endocarditis, polyserositis, abortions and abscesses. S. suis has also been implicated in disease in humans, especially among abattoir workers and swine and pork handlers. In humans, S. suis type 2 can cause meningitis, which may result in permanent hearing loss, septicaemia, endocarditis and death. The pathogenic mechanism of S. suis is not well defined. Several virulence factors have been identified, but their roles in pathogenesis and disease have not been well elucidated. Much work is in progress on characterization of virulence factors and mechanisms, with emphasis on the control of the disease. Because of the non-availability of suitable immunoprophylaxis, control of S. suis infection has depended mainly on the use of antimicrobials.     

罗非鱼链球菌的分离鉴定

从济南、泰安、枣庄、德州等地的几个罗非鱼养殖场发病的罗非鱼中，分离到一株G^ 链球菌。将该菌人工感染罗非鱼，证实为致病菌。对该菌的形态特征、培养特性、生化特性、致病特性、对药物的敏感性等进行了试验，证明核菌为S.iniae。     

Identification and characterization of Streptococcus suis

A total of 188 Streptococcus suis strains isolated from pigs with various lesions, mainly bronchopneumonia, were identified using classical biochemical methods and using the API 20 STREP system. The serological classification was performed by precipitation reactions after Lancefield extraction, slide-coagglutinations and capsular reaction tests. Fifty-nine strains belonged to Types 1, 1/2 or 2, 78 strains to Types 3-8 and 51 strains were non-typable. The results of the different tests and the biochemical differences between the different serotypes are discussed.     

鹅链球菌的分离与鉴定

安徽某种鹅场70—120日龄种鹅发生以败血症为特征的急性传染病。从该鹅场采集病料对该病病原进行分离，细菌学检验，并进行生化试验，动物接种试验等，证实为链球菌病。     

猪链球菌的分离与鉴定

文章对分离的4株猪源链球菌进行了鉴定，其形态，染色、培养及生化特性均符合链球菌的特点。用链球菌乳胶分型诊断液检潮上述分离株，均不在其检测范围，即不属于链球菌兰氏分群的A-G群，但它们凝集猪链球菌2型抗血清。分离株对小鼠不致病，而对家兔则可致病。