猪源性链球菌的耐药性分析

为了找到对猪链球菌病疗效较好的药物,本实验用平皿二倍稀释法,测定了临床分离的27株链球菌的MIC,耐药性监测的结果表明链球菌对所测12种药物有11种产生了不同程度的耐药性,只有盐酸克林霉素和阿莫西林对临床所分离的链球菌比较敏感,MIC50分别为0.125μg/mL、4μg/mL。     

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...     

猪大肠杆菌和链球菌的分离鉴定及耐药性分析

猪大肠杆菌病和链球菌病是养猪业的多发病症,而且常与其他细菌性或者病毒性病症并发,给养猪业带来严重的经济损失。本文就猪大肠杆菌和链球菌的分离鉴定及耐药性做进一步探讨与分析,旨在为临床药品的合理选用,猪大肠杆菌病及链球菌病的防治提供科学依据。     

猪耐药性链球菌感染的诊治

2003年4月初,凯里市鸭塘镇养猪户李某所养的三窝仔猪(28头)相继发病,死亡18头,死亡率为64%,诊断为耐药性链球菌感染。现将情况报道如下:1发病情况2003年4月3日,李某发现所养仔猪(16日龄)有零星的拉稀症状,疑是大肠埃希氏菌感染,遂给发病仔猪口服庆大霉素,但未见改善,改用氨苄青霉素,并肌注黄连素,病猪症状减轻,2～3日后再复发,并排出带泡沫、脓汁样稀粪,不再吮奶,倒地抽搐或转圈尖叫,不久死亡。一周后几乎所有仔猪均出现食欲下降、精神萎顿、拉稀等症状。部分仔猪如前述经过,最终死亡,至4月16日,已死亡14头。2临诊症状病猪倒地,欲挣扎站起,…     

不同动物源性链球菌的耐药性分析

通过形态观察、革兰氏染色及生化试验分离鉴定共获得28株猪源及牛源链球菌。采用琼脂二倍稀释法测定7种抗菌药物对28株链球菌的最小抑菌浓度（MIC）,其中绝大多数受试菌株呈多重耐药性。研究结果表明,不同动物源性链球菌对抗菌药物的抗菌谱不同,揭示的耐药规律对指导临床用药具有重要意义。     

猪溶血性链球菌对复合酚消毒剂的耐药性

以亚致死浓度（１∶５００）复合酚多次处理猪溶血性链球菌Ｃ５５１６,得其第１９代菌（Ｆ１９）。Ｆ１９可抵抗推荐浓度复合酚（１∶３００,可完全杀死原代菌）;在普通肉汤多次传代,未见其对复合酚抵抗力下降;用碱裂解法提取Ｆ１９质粒ＤＮＡ,经琼脂糖凝胶电泳,发现１条明亮的电泳带。此电泳带与Ｆ１９对复合酚的抵抗力的关系尚需进一步研究。     

牦牛源链球菌的分离鉴定及耐药性分析

【目的】了解西藏拉萨地区牦牛链球菌的感染情况、致病性及其耐药性,为牦牛源链球菌的研究提供新的数据。【方法】对55份牦牛鼻拭子进行细菌分离培养、菌落形态观察、革兰氏染色镜检、生化鉴定、16S rRNA序列PCR扩增以鉴定分离菌的种属特性。通过人工感染试验小鼠评价分离菌的致病性,采用药敏纸片扩散法检测分离菌的耐药性。【结果】分离菌在血平板上长出灰白色、表面光滑的α溶血圆形菌落,革兰氏染色镜检呈链状排列的阳性球菌。分离菌可发酵葡萄糖、乳糖、海藻糖和山梨醇,不发酵麦芽糖和甘油,硝酸盐还原试验、靛基质试验、V-P试验和MR试验均呈阴性。经16S rRNA基因序列比对分析,确定有25株链球菌(Tibet-1～Tibet-25),检出率为45.46%(25/55),其中17株多动物链球菌,8株马链球菌。分离菌16S rRNA基因序列与NCBI上已发布的链球菌相似性在97.04%～99.77%之间,其中Tibet-1、Tibet-2、Tibet-3、Tibet-5、Tibet-9、Tibet-10、Tibet-11、Tibet-14、Tibet-15、Tibet-16、Tibet-17共11株牦牛源多...     

猪的链球菌性脑膜炎

猪链球菌性脑膜炎广泛发生于世界各国,并且在近10年来成为某些国家的主要猪病之一.此病的主要病原体是猪链球菌(Streptococcus suis),属兰氏菲尔德 D 族,至少可分为9种血清型.9种血清型中,Ⅰ型是最常见的,也是本文论述的重点.Ⅰ型猪链球菌在没有其他重要猪病的国家里以及在久已广泛实行集约化养猪生产的国家内,极为重要.     

猪源粪肠球菌的基因型及耐药性分析

为了解上海地区规模化猪场中粪肠球菌的耐药性和基因型,2013年3月-2014年5月从上海地区10个规模化养猪场收集到分离鉴定的粪肠球菌133株,采用微量肉汤稀释法对12种抗菌药物进行药敏试验,采用PCR技术分别检测分离株中β-内酰胺类抗生素耐药相关基因(TEM)、氨基糖苷类抗生素耐药相关基因[aac(6’)/aph(2")和aph(3’)-Ⅲ和ant(6)-Ⅰ]、四环素耐药相关基因(tetM)、红霉素耐药相关基因(ermB和mefA)和万古霉素耐药相关基因(vanA和vanB)。结果显示,在133株粪肠球菌中,耐药基因ermB、tetM、TEM、ant(6)-Ⅰ、aac(6’)/aph2"、aph(3’)-Ⅲ、vanA的检出率分别为:95.5%(127/133)、91.0%(121/133)、63.2%(84/133)、45.9%(61/133)、42.1%(56/133)、24.1%(32/133)、3.0%(4/133);未检出mefA和vanB基因的菌株。分离菌株对12种抗菌药物的耐药性较为严重,且以6~9耐为主要耐药株,占81.2%。试验表明,上海地区猪源粪肠球菌多重耐药现象严重,携带抗菌药物相关耐药基因是导致分离株耐药的主要原因。     

奶牛源乳房链球菌毒力与耐药性分析

乳房链球菌是导致奶牛乳房炎的主要病原菌之一,但近年来研究发现乳房链球菌也与奶牛子宫内的感染相关,导致子宫内膜炎的发生.采集甘肃省不同地区5个牧场患有子宫内膜炎奶牛的子宫黏液样品48份,共计分离得到18株乳房链球菌.然后通过CAMP试验来检测分离菌株的协同溶血作用,采用普通PCR检测10种已知毒力基因(hasA、hasB...     

Streptococcus suis isolated from pigs in Finland

A total of 58 Streptococcus suis strains were isolated from deceased pigs submitted to the National Veterinary Institute, Regional Laboratory in Kuopio, Finland, over a 3 1/2 year period, most frequently from cases of pneumonia. The bacteria were isolated from cases of meningitis, sepsis, rhinitis, endocarditis and abortion. S. suis was also isolated from nasal cavity, lung and brain of some sick piglets without signs of inflammation. Further S. suis was detected in 12 out of 107 tonsils of healthy fatteners tested. S. suis strains were identified by biochemical methods followed by typing. The most common capsular types were 7, 3 and 2, respectively. Only one type 1 strain and no types 6 and 9 strains were found. All S. suis strains tested were sensitive to penicillin and ampicillin.S. suis is not uncommon in Finnish pig herds. S. suis may be regarded as a potentially pathogenic organism which under certain predisposing conditions may cause serious disease.     

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.     

屠宰场猪链球菌分离菌株分型及其致病性和耐药性分析

为了解吉林省猪链球菌的流行情况,从屠宰场采集的猪咽拭子和鼻拭子样品中分离鉴定猪链球菌,并进行菌株血清型、基因型和毒力表型的鉴定,以及致病性和耐药性的分析。结果表明,从100份样品中共分离鉴定猪链球菌104株,其中29株鉴定为血清2型、9型和1型等几种常见的致病性血清型,其他75株不属于常见的致病性血清型。血清2型的菌株中,2株经鉴定为ST1基因型和mrp+epf+sly+毒力型,并经动物试验鉴定为强毒菌株;其他菌株均为ST28基因型和mrp+epf-sly-毒力型,具有中等毒力。血清9型的菌株,均为mrp-epf-sly-毒力型,动物试验鉴定均为强毒菌株。根据Kirby-Bauer纸片扩散法的药敏试验结果,98%的猪链球菌分离株对四环素耐药;对大环内酯类、克林霉素和链霉素的耐药率都在50%以上;对β-内酰胺类、氯霉素和喹诺酮类抗生素的耐药率小于20%。总体分析,从屠宰场分离的猪链球菌强毒菌株所占的比例并不高,但是菌株多重耐药的情况非常严重。     

Clonal distribution of Streptococcus suis isolated from diseased pigs in the central region of Chile

The characteristics of 29 Chilean field strains of Streptococcus suis recovered between 2007 and 2011 from pigs with clinical signs at different farms were studied. Serotyping with use of the coagglutination test revealed that all but 1 strain belonged to serotype 6; the remaining strain was serotype 22. All the serotype-6 strains were suilysin (hemolysin)-negative; in addition, they were found to be genotypically homogeneous by enterobacterial repetitive intergenic consensus sequence-based polymerase chain reaction (ERIC-PCR) and sensitive to ampicillin, ceftiofur, penicillin, and trimethoprim/sulfamethoxazole. The results indicate that, in contrast to what is generally observed in other countries, a single clone of S. suis was isolated from diseased pigs in the central region of Chile.     

猪链球菌扁桃体分离株的毒力因子分布特征与致病性

本研究设计并合成7对引物,用PCR方法对猪链球菌7种主要毒力因子,包括谷氨酸脱氢酶(gdh)、溶血素(sly)、胞外蛋白因子(ef)、溶茵酶释放蛋白(mrp)、纤连蛋白/血纤蛋白原结合蛋白(fpbs)、三磷酸甘油醛脱氢酶(gadph)和毒力相关序列orf2进行检测,分析了29株猪链球菌扁桃体分离株的毒力因子分布特征.在被检的25株2型菌株中,共检测出7个基因型.其中10株(40%)的基因型为cps2/gdh+/sly+/ef+/mrp+/fbps+/gadph+/orf2+,7株(28%)表现为cps2/gdh+/sly-/ef-/mrp+/fbps+/gadph+/orf2+,4株(16%)表现为eps2/gdh+/sly-/ef+/mrp+/fbps+/gadph+/orl2+,基因型表现为eps2/gdh+/sly+/ef+/mrp+/fbps+/gadph+/orf2-、cps2/gdh+/sly-/ef-/mrp+/fbps+/gadph+/orf2-、eps2/gdh+/sly-/ef-/mrp*/fbps+/gadph+/orf2+、eps2/gdh+/sly-/ef-/mrp-/fbps-/gadph+/orf2-各1株;1株猪链球菌7型(SS7)分离株,基因型表现为cps7/gdh+/sly+/ef-/mrp-/fbps+/gadph+/orf2+;3株猪链球茵9型(SS9)扁桃体分离株,均表现为cps9/gdh+/sly-/ef-/mrp-/fbps+/gadph+/orf2+.可见我国SS分离株的毒力基因分布较为复杂,而且SS2的优势流行菌株是同时具有多种毒力因子的高致病茵株.通过对不同毒力基因型毒株对西藏小型猪的感染试验发现:毒力基因型为cps2/gdh+/sly-/ef+/mrp+/fbps+/gadph+/orf2+的健康扁桃体分离株SH06-21D对西藏小型猪有较强的致病性,仅次于标准株HA9801,而基因型为sly-/ef-/mrp-/fbps-/gadph+/orf2-的健康扁桃体分离株GZ06-122B对西藏小型猪不表现明显的致病性.     

Prevalence of the suilysin gene in Streptococcus suis strains isolated from diseased and healthy carrier pigs

Knowledge of virulence factors of Streptococcus suis is limited. Several virulence factor candidates have been proposed, among them suilysin, which is responsible for a toxic effect on epithelial cells. The aim of this study was to detect the suilysin gene sequence in Streptococcus suis strains of various origin. In total 63 Streptococcus suis isolates were investigated. Forty four of them originated from tissues of streptococcosis affected animals. The remaining 19 strains were isolated from tonsils of healthy carrier pigs. Suilysin gene specific sequence was detected in 79% of the strains tested. In isolates obtained from pigs with signs of streptococcosis this gene sequence was recorded in 85% of cases. In Streptococcus suis strains isolated from healthy carrier pigs the suilysin gene was detected in 63% of the isolates. It seems that suilysin toxic activity is only one of the many steps involved in the pathogenesis of Streptococcus suis infection and that strain's virulence cannot be stated only on the basis of suilysin gene sequence presence.     

Biochemical analysis, cpn60 and 16S rDNA sequence data indicate that Streptococcus suis serotypes 32 and 34, isolated from pigs, are Streptococcus orisratti

Streptococcus suis serotypes have traditionally been identified by morphology, biochemical profiling and serotyping. Analysis of the sequences of 16S rRNA and cpn60 genes of the 35 characterized serotypes of S. suis led to the observation that two serotypes 32 and 34, are significantly distinct from other S. suis serotypes and may represent a distinct species. Here we present DNA sequence data and biochemical profiles which indicate that S. suis serotypes 32 and 34, isolated from pigs, are clustered with Streptococcus orisratti, a Voges-Proskauer negative, alpha-haemolytic, aesculin-hydrolytic, Lancefield group A streptococcus isolated from the teeth of rats.