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1.
对采集于云南传统乳制品中乳酸菌的种类及优势菌群的分布情况进行了研究.从采集的8份样品中共分离获得73株乳酸菌,分属于5个属的13个种.对乳酸菌优势菌群分析,发现肠球菌、乳球菌和同型发酵乳杆菌为主要菌群,分别占乳酸菌总数的20%、27%和20%.  相似文献   

2.
利用编码3-磷酸甘油醛脱氢酶的gapC基因具有高度特异性的特点,建立PCR方法鉴定与奶牛乳房炎相关的链球菌。根据已有gapC基因序列设计1对引物,以分离自患乳房炎奶牛乳样的10株革兰阳性球菌、10株革兰阳性杆菌、10株革兰阴性杆菌作为待检菌株,进行PCR扩增。结果表明,在10株革兰阳性球菌中,有8株球菌可以扩增出约1011bp的目的条带,而其他2株革兰阳性球菌及20株杆菌均无相应PCR产物出现。通过传统的生化鉴定与16S rDNA序列分析相结合证实,能扩出gapC基因的8株革兰阳性球菌分别为乳房链球菌(Streptococcus uberis)、牛链球菌(S.bovis)与猪链球菌(S.suis)。说明基于gapC基因的PCR方法,用于鉴定奶牛乳房炎相关链球菌具有较强的特异性。  相似文献   

3.
Traditional microbiological methods for identification of Streptococcus spp. causing bovine mastitis have been demonstrated to be less than highly reliable. PCR-RFLP analysis of 16S-23S ribosomal DNA was used to characterise seven reference strains of streptococcal mastitis pathogens as well as four reference strains of other gram-positive, catalase-negative cocci of bovine origin to allow comparative identification of field isolates. RFLP analysis of PCR products, using a combination of two restriction endonucleases in single reactions (HaeIII and AluI, HaeIII and RsaI or AluI and RsaI) generated unique patterns for species of Streptococcus, Enterococcus and Lactococcus. One hundred field isolates of Streptococcus spp. collected from cows with clinical or subclinical mastitis were tested. Fifty-seven isolates, classified by conventional tests as S. uberis, were identified as 47 S. uberis and six S. parauberis by their unique RFLP patterns. The remaining four isolates had RFLP patterns distinct from the reference strains and two of these were identified as closely related to S. iniae and two to Aerococcus viridans by 16S rRNA sequencing. Conventional identification of 17 S. agalactiae and 26 S. dysgalactiae subsp. dysgalactiae was confirmed by RFLP. Use of a combination of restriction enzymes in a single tube enabled the rapid, accurate, cost effective and easily performed identification of all major streptococcal mastitis pathogens.  相似文献   

4.
A total of 26 samples of Matsoni were collected in Georgia. From these samples 80 strains of lactic acid cocci and 173 strains of lactobacilli were isolated. The number of lactic acid bacteria varied between 105 and 1010 colony forming unit (CFU)/mL. All the isolated lactic acid bacteria were thermophilic bacteria that could grow at 45°C. The predominant lactic acid bacteria were Streptococcus thermophilus and Lactobacillus delbrueckii spp. bulgaricus in 25 samples of Matsoni, while Lactobacillus helveticus was also a predominant species, together with the two previous species in one sample of Matsoni. We showed there was diversity in both S. thermophilus and L. delbrueckii spp. bulgaricus at the strain level by randomly amplified polymorphic DNA analysis.  相似文献   

5.
The growth and the toxin (i.e. hemolysin) producing capacity of Corynebacterium pyogenes were studied in monocultures and in co-cultures with 1 or more of the organisms frequently accompanying it in summer mastitis in cattle (Peptococcus indolicus, Stuart-Schwan cocci, Bacteroides melaninogenicus subsp. levii, Fusobacterium necrophorum and Streptococcus dysgalactiae) or with organisms seldom associated with summer mastitis (Streptococcus uberis, Streptococcus agalactiae, non-toxic staphylococci and Escherichia coli).Pc. indolicus, and to some extent also Stuart-Schwan cocci, stimulated the growth as well as the hemolysin producing capacity of Gb. pyogenes (Table 1) while Str. dysgalactiae, Str. uberis, Str. agalactiae, E. coli and the majority of the staphylococci reduced these activities. Most F. necrophorum strains stimulated the growth, but not the hemolytic activity. With B. melaninogenicus the results were inconclusive.The effect of Pc. indolicus appeared to be associated with the production of a filterable factor (Tables 2 and 3).Mouse toxicity and hemolytic activity of culture filtrates were closely correlated (Table 4).  相似文献   

6.
对昆明地区多个奶牛场的奶牛临床型乳房炎病原菌进行分离、鉴定,从114份乳样中共分离出细菌13种305株,经培养特性、染色镜检、生化鉴定等,鉴定出金黄色葡萄球菌63株,占20.66%;表皮葡萄球菌26株,占8.52%;无乳链球菌53株,占17.38%;停乳链球菌23株,占7.54%;乳房链球菌19株,占6.23%;乳链球菌14株,占4.59%;粪链球菌15株,占4.92%;化脓链球菌14株,占4.59%;大肠杆菌48株,占15.74%;真菌12株,占3.93%。分别对分离菌株进行17种药物的敏感性试验,除真菌外,所有菌株对庆大霉素、新霉素、环丙沙星、诺氟沙星、林可霉素、乳肿康均高度敏感,对临床常用的青霉素、链霉素、鱼腥草等具有较强的耐药性。  相似文献   

7.
为了解9型猪链球菌广东分离株毒力因子基因型、基因变异和进化情况,本试验采集发病猪脑脊液、关节液、脾脏、肝脏、淋巴结进行细菌分离培养和生化鉴定,采用PCR方法鉴定其血清型及部分毒力基因,对cps9D、gdh、gapdh与orf2基因进行序列测定和分析,并构建系统发育树。结果显示,分离菌镜检为革兰氏阳性链状球菌,在鲜血琼脂平板中呈β溶血,可发酵大多数糖类,能成功扩增cps9D基因,含重要的保守基因gdh及毒力基因gapdh和orf2,表明分离菌株为9型猪链球菌。分离菌株cps9D、gdh、gapdh、orf2基因核苷酸序列与GenBank上国内外参考菌株的同源性分别为95.9%~100.0%、98.6%~99.8%、98.7%~99.6%和95.5%~99.9%,说明分离菌株与国内外其他9型猪链球菌毒株核苷酸同源性都较高,且与国内外的流行毒株基本一致,未发生太大的变异。系统发育树表明,分离株与国内外来源不同的猪链球菌分离株同源性高,亲缘关系密切。  相似文献   

8.
Two dogs were examined for clinical signs of chronic gastrointestinal disease. Duodenal mucosal biopsy specimens, obtained endoscopically, revealed histologic lesions of adherent gram-positive cocci on the villus epithelium of both dogs. The positive gram stain and morphologic features of the adherent cocci were suggestive of Streptococcus organisms. Indirect tests for intestinal bacterial overgrowth were not diagnostic, suggesting that the adherent cocci were a primary lesion. Rapid clinical response following dietary manipulation and the initiation of medical management was observed in both dogs. The dogs of this report draw similarities to Streptococcus durans infection previously reported in pigs, foals, and a single pup. The pathogenesis of enteric disease associated with adherent gram-positive cocci in dogs remains ill-defined.  相似文献   

9.
Between 1998 and 2001, mortalities due to verrucous endocarditis were experienced at several mink farms. Gram-positive cocci were isolated from the endocardium of all the animals examined but not always from other internal organs. Almost all the isolates were identified as Streptococcus bovis and only a few isolates belonged to other Streptococcus species. Typing by pulsed-field gel electrophoresis of a selection of isolates revealed several patterns and several different clones. Attempts to reproduce disease by the injection of cultures of a field isolate into healthy mink failed.  相似文献   

10.
11.
Forty-nine strains of microaerophilic gram-positive cocci (Stuart-Schwan cocci) isolated from summer mastitis, "pyogenes"-mastitis, other pyogenic conditions of Danish cattle and swine, and from the sheep headfly Hydrotaea irritans were biochemically characterized with the API 50 CH and API ZYM test kit systems, and screened for production of a variety of extracellular enzymes by agar plate methods. For comparison 4 strains isolated from Swedish cases of heifer and dry cow mastitis were included in the study. Similarity calculations indicated a high degree of homogeneity within the strains studied (similarity level 92%; group mean similarity 87%). The strains probably represent one species, although the taxonomic position of the organism remains unclear. The biochemical feature of the strains studied were very similar for strains isolated from cases of summer mastitis and strains from other sources of origin. It is suggested that the Stuart-Schwan coccus occurs as a natural cohabitant to Actinomyces pyogenes, Peptostreptococcus indolicus and the anaerobic organism characteristic of the bacterial complex isolated from summer mastitis and similar pyogenic conditions in ruminants and swine.  相似文献   

12.
为确诊引起广东省某规模化猪场保育仔猪发生死亡的病因,本试验采集病猪肝脏、脾脏、心脏、脑、关节液和淋巴结等病料进行细菌分离,并对分离菌株进行纯化培养、菌落形态观察、革兰氏染色、形态学观察、生化试验,用血清型特异性引物进行PCR扩增,并进行毒力基因检测、药敏试验、生长曲线测定及动物试验。结果显示,分离菌株在成牛血清琼脂平板上呈圆形、灰白色、表面光滑、边缘整齐的菌落,镜检为革兰氏阳性球菌,呈链状排列。该菌株的生化试验结果符合链球菌的特征,PCR扩增结果显示猪链球菌保守基因片段(gdh和gapdh)和猪2型链球菌特异的cps2J基因片段均为阳性,表明该分离菌株为猪2型链球菌。毒力基因检测结果表明,该菌株毒力因子基因型为gdh+/gapdh+/epf+/mrp+/sly+/orf2+/fbps+。分离菌株用营养肉汤培养6 h达到对数生长期,培养10 h的菌液D600 nm值为0.310。药敏试验结果表明,该菌株对青霉素、阿莫西林、阿莫西林-克拉维酸钾等药物敏感,但对强力霉素耐药。动物试验结果表明,感染分离株的BALB/c小鼠未出现死亡且无明显临床症状,毒力较低。本研究为该猪场链球菌病的防控提供了重要参考信息。  相似文献   

13.
Multiple outbreaks of acute severe fibrinopurulent lesions of the eyelids occurred in chickens and turkeys. Lesions began as tiny foci of epidermal necrosis and ulceration and spread to involve the entire eyelid. Scabs overlying the epidermis contained large gram-positive cocci; lesser numbers of small cocci and gram-negative bacilli were in more superficial areas. Staphylococcus hyicus was isolated from birds in all stages of the disease. Escherichia coli and Streptococcus sp. were isolated only during severe stages; no anaerobic bacterial pathogens were isolated. Vasculitis and perivascular lymphocytic infiltrates in deep layers of the dermis suggested that a staphylococcal toxin may have been involved. The disease was not reproduced by scarifying S. hyicus onto the eyelids or by intravenous inoculation of retrovirus-infected chickens.  相似文献   

14.
The objective of this study was to isolate and identify Streptococcus bovis from yak, and detect their hemolytic, pathogenicity and antimicrobial susceptibility. 45 fecal samples collected from the diarrheal yaks in Aba state in Northwest Sichuan province were used to isolate Streptococcus bovis with sheep blood culture media under 37℃ and 5% CO2 condition cultured for 24 h. The isolated bacteria were identified by 16S rRNA amplification and sequencing. Total 14 Streptococcus bovis were identified, among which, 8 Streptococcus lutetiensis strains and 6 Streptococcus gallolyticus strains. 9 Streptococcus bovis strains showed α hemolytic, and 5 Streptococcus bovis showed β hemolytic. Both Streptococcus lutetiensis and Streptococcus gallolyticus caused the experimental mice mild diarrhea. The isolated 14 Streptococcus bovis were sensitive to penicillin, cefotaxime, vacomycin, acetylspiramycin, ciprofloxacin, rifampicin, teicoplanin, ampicillin and gentamicin, and highly tolerant to streptomycin, kanamycin, lincomycin, erythrocin, tetracycline and clindamycin.This study illustrated the biological characteristics of the isolated Streptococcus bovis from yak, which made the basis for the prevention and control of diseases caused by Streptococcus bovis.  相似文献   

15.
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.  相似文献   

16.
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。  相似文献   

17.
奶牛乳房炎类型与病原菌感染之间相关性的研究   总被引:14,自引:0,他引:14  
通过对 2 858份不同类型乳房炎奶样的细菌学检验 ,结果分得细菌共 2 4种 31 38株 ,其中分离鉴定出与乳房炎有密切关系的病原菌 1 2种 1 96 8株 ,病原菌检出率为 6 2 .72 %,各种类型乳房炎常见病原菌的区系分布总的趋势是一致的 ,绝大部分是以无乳链球菌为主 ,其次是停乳链球菌、金黄色葡萄球菌、大肠杆菌和乳房链球菌等。但不同类型之间、同一类型不同等级之间及隐性乳房炎泌乳期和干奶前之间奶样的细菌分布和细菌种类有所不同。乳房炎的轻重与病原菌检出率呈正相关。奶牛乳房即使在健康的状态下也存在着带菌现象  相似文献   

18.
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。  相似文献   

19.
Streptococcus dysgalactiae serogroup C, G and L strains were investigated by polymerase chain reaction (PCR) using oligonucleotide primers designed according to species‐specific parts of the 16S–23S rDNA intergenic spacer region. The oligonucleotide primers with specificity for the 16S–23S rDNA intergenic spacer region allowed a correct identification of all S. dysgalactiae serogroups C, G and L strains investigated. No cross‐reactivities could be observed with any of the control strains indicating the usefulness of PCR‐technology to identify the serologically heterogeneous species S. dysgalactiae.  相似文献   

20.
Identification and characterization of staphylococci isolated from cats   总被引:1,自引:0,他引:1  
Staphylococcus simulans was found to be the most common staphylococcal species present on the healthy skin and in the nares of cats. S. aureus was the most frequent Staphylococcus species in lesions. Most of the S. aureus strains showed the characteristics of the human ecovar. Other strains isolated formed a heterogenic collection in which not less than 13 species were represented. One of these, S. epidermidis, was almost exclusively associated with lesions. It was concluded that coagulase-positive staphylococci are not endogenous to cats. Staphylococci from other sources, most frequently from man, are often associated with lesions in these animals.  相似文献   

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