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1.
Thirty‐five Yersinia enterocolitica strains isolated from humans, pigs and foxes were analysed by genotyping including intergenic transcribed sequence (ITS) profiling, REP‐ and ERIC‐PCR. ERIC‐PCR revealed the presence of seven different genotypes. Amplification of the 16S‐23S rDNA spacer region by ITS profiling gave similar results with nine different genotypes. REP‐PCR was found to be more discriminatory for typing of Y. enterocolitica than ERIC‐PCR and ITS profiling. Fifteen different DNA patterns were obtained by this technique. Based on data obtained by three methods it was found that: (i) Y. enterocolitica strains belonging to the same serotype can represent different genotypes and vice versa; (ii) isolates recovered from humans, pigs and foxes exhibit limited heterogeneity and, independent of the origin, one or two prevailing genotypes were always observed; and (iii) many human Y. enterocolitica isolates shared common genotypes with porcine isolates.  相似文献   

2.
Thirty-one Salmonella Enteritidis strains isolated from chickens, broilers and hens were analysed by genotypic typing including REP-PCR. ERIC-PCR and ITS profiling (PCR-ribotyping). Analysis of DNA banding patterns generated by REP-PCR revealed the presence of 22 different genotypes, which were grouped by dendrogram analysis into three distinct lineages (maximum similarity approx. 50%). Each isolate of S. Enteritidis analysed by ERIC-PCR generated an individual DNA pattern. Again, these isolates could be divided into three distinct genomic groups (maximum similarity approx. 60%) by their ERIC-PCR fingerprints. REP- and ERIC-PCR were found to be more discriminatory for typing of S. Enteritidis than ITS profiling. Amplification of the 16S-23S rDNA spacer region gave nine different profiles of DNA, subdivided into two closely related groups by dendrogram analysis. In summary, data obtained by genotyping methods for S. Enteritidis isolates from regions located in the south-west and the central parts of Poland revealed an enormous heterogeneity among analysed samples, and proved that REP- and ERIC-PCR are highly discriminatory techniques, which can be used, in addition to conventional methods, in epidemiological studies of S. Enteritidis infections.  相似文献   

3.
The subject of this study was thirty nine strains of Yersinia enterocolitica, isolated from faeces of humans who showed symptoms typical of intestinal yersiniosis, and seventy strains of Y enterocolitica, four strains of Y. pseudotuberculosis, and one strain of Y. kristensenii from healthy pigs. In the population tested the following serogroups appeared: O3, O9, O2, O5. A PCR was used to detect the presence of pathogenic chromosomal markers, such as myfA and inv genes of the tested Yersinia species. Among Y. enterocolitica strains isolated from humans and belonging to serogroup O3 (thirty four strains) and serogroup O9 (five strains) thirty three Y. enterocolitica O3 strains and four Y. enterocolifica O9 strains, gave a positive reaction to the nmyfA gene, yielding a fragment of 280 base pairs (bp). Among seventy Y. enterocolitica strains isolated from pigs forty strains belonging to serogroup O3 and fifteen strains belonging to serogroup O9 gave a positive reaction to the myfA gene. The presence of 390 bp amplified products, corresponding to the inv gene fragment, was detected in PCR products of three Y pseudotlluberculosis strains from pigs and only in one Y. enterocolitica O3 strain from humans, which had no myfA gene. The results obtained show that the myfA gene is only present in the strains that belong to pathogenic serotypes of Y. enterocolitica. The myfA gene prevailed in the Y. enterocolitica O3 and O9 strains from humans but was less common in the Y. enterocolitica O3 and O9 strains from pigs.  相似文献   

4.
The aim of the present study was to evaluate the lytic activity of three bacteriophages on Yersinia enterocolitica strains isolated from humans and pigs. The Y. enterocolitica strains tested belonged to 0:3, 0:9 and 0:2 serogroups. The ZD5 phage was obtained from a water sample, but remaining phages were obtained from the lysogenic Y. frederiksenii 7291 and Y. enterocolitica 8684 strains. All the Y. enterocolitica strains tested which belonged to 0:9 serogroup did not show any susceptibility to the bacteriophages used. The bacteriophages tested showed different lytic activity on the Y. enterocolitica 0:3 strains investigated. The phage susceptibility of Y. enterocolitica 0:3 strains revealed 9 different phage patterns. ZD5 phage showed the highest lytic activity, because it produced confluent lysis of the most Y. enterocolitica 0:3 strains tested. The Y. enterocolitica 0:2 strains isolated from pigs showed the similar phage susceptibility. The Y. kristensenii and Y. pseudotuberculosis strains tested were not sensitive to the bacteriophages used.  相似文献   

5.
An enzyme immunoassay (ELISA) was developed to detect antibodies in pigs against the lipopolysaccharidic antigen of the three serotypes of Yersinia enterocolitica mostly associated with human infections. Recent epidemiological evidence has demonstrated that pigs and pork are important sources of yersiniosis in humans. The purpose of this study was to clarify the use of an ELISA to detect swine carriers of this enteroinvasive bacteria by examining seroconversion and tissue distribution of Y. enterocolitica following experimental infection and then screening pigs at a slaughterhouse by bacterial culture and ELISA. It was observed that seroconversion occurred in animals experimentally inoculated with Y. enterocolitica but not with other enterobacteria. It was also found that 27% of swine at a slaughterhouse carried the bacterium in their tonsils and/or intestinal tract, whereas 66% showed serological evidence of previous infection. About 6% of swine at slaughter were culture-positive, but seronegative. Although, similar numbers of swine showed serological evidence of previous infection by each of the three Y. enterocolitica serotypes tested, virtually all culture isolates belonged to serotype O:3. This ELISA appears as a valuable control tool that can be used, in conjunction with culture, to identify pigs or herds infected by strains of Y. enterocolitica associated with human infections.  相似文献   

6.
Caseous lymphadenitis is an infectious sheep and goats disease caused by Corynebacterium pseudotuberculosis and characterized by abscesses in superficial and visceral lymph nodes. C. pseudotuberculosis strains isolated from these hosts have been shown to be very difficult to type by the existing methods. The aim of this study is evaluating the potential of the Enterobacterial Repetitive Intergenic Consensus (ERIC-PCR) as a tool for molecular typing of C. pseudotuberculosis strains isolated in sheep. One hundred and twenty seven isolates of C. pseudotuberculosis were isolated from lesions suspected to have had caseous lymphadenitis collected from sheep at the slaughterhouse. Animals were from 24 flocks in 13 municipalities of the Minas Gerais State, Brazil. Species identification of the isolates was performed by routine biochemical tests and mPCR. Fingerprint was performed by RAPD using ERIC-1R, ERIC-2 and ERIC-1R+ERIC-2 primers. Seventeen different genotypes were generated by ERIC 1-PCR, 21 genotypes by ERIC 2-PCR and 21 genotypes by ERIC 1+2-PCR. Hunter-Gaston Discrimination Index (HGDI) found for ERIC 1, ERIC 2, ERIC 1+2 PCR were 0.69, 0.87, and 0.84, respectively. For most herds evaluated observed at most three different genotypes among isolates from animals of these property, in all ERIC-PCR assays. However a few flocks observed between four and nine genotypes per flock. The W Kendall value found for correlation among the three techniques of ERIC-PCR was 0.91 (P<5.0 x 10(-6)). The results show that ERIC-PCR has good discriminatory power and advantages over other DNA-based typing methods, making it a useful tool to discriminate C. pseudotuberculosis isolates.  相似文献   

7.
The 150 Y enterocolitica strains isolated from humans and from pigs belonged to biotypes 4 (68.7%), 1A (18.7%) and 2 (4%), or were biochemically untypeable (8.6%). Biotype 4 was comprised of Y. enterocolitica strains representing serotype O:3, within biotype 1A the strains either belonged to serotypes O:5 and O:6 or were untypeable, and biotype 2 was represented by the strains of serotype O:9. The strains which were biochemically untypeable belonged to serotypes O:5, O:6 and O:3. Among the strains tested there also were those of an unidentified biotype and serotype. Nearly all the strains of biotype 1A represented genotype ystB+myfA+, and few belonged to genotype ystB+. The presence of the ystB gene in the strains of biotype 1A and only occasional occurrence of the gene in the other biotypes makes ystB a distinguishing marker of biotype 1A. The strains of genotype ystA+ail+myfA+yadA+ predominated in biotype 4 (serotype O:3). The strains of biotype 2 (serotype O:9) represented genotype ystA+ail+myfA+, and the plasmid yadA gene was detected in some of them. Within the group of biochemically untypeable strains ystB- and myfA-specific PCR products were mainly obtained. The genotypes determined for the tested biotypes and serotypes of Y. enterocolitica, based upon the selected genes of virulence, can be applied as distinguishing markers and indicators of the potential virulence of Y. enterocolitica strains, excluding bioserotyping.  相似文献   

8.
Twenty-six Campylobacter jejuni strains isolated from poultry were analyzed by genotypic typing including ITS-profiling, REP- and ERIC-PCR. ITS-profiling revealed the presence of 8 different genotypes. Amplification of REP sequences by PCR gave similar results with 10 different genotypes. ERIC-PCR was found to be the most discriminatory for typing C. jejuni. As many as 13 different DNA patterns were obtained with this technique. Based on data obtained it was found that C. jejuni isolates recovered from broilers at the slaughterhouses in southwest Poland are characterized by a high degree of genetic heterogeneity.  相似文献   

9.
Diarrhoeic faecal samples from 210 humans and 192 swine were screened for Yersinia enterocolitica in 1990. Ten and 8 Y. enterocolitica strains were isolated from pig and man, respectively. The isolates were found to belong to Wauter's biotypes 1, 2, 3 and 4. Biotype 2 was isolated mainly from human stool samples. Biotype 3 was found only in swine while biotypes 1 and 4 were isolated from both man and swine. All the 18 strains showed varying degrees of sensitivity to antibiotics used in this investigation. The organisms were consistent in their resistance to ampicillin and penicillin.  相似文献   

10.
Fourteen strains of Yersinia species isolated from apparently healthy pigs and cattle in Nigeria were screened for four virulence markers using six test systems. These were two in vitro assays, namely, calcium dependency and autoagglutination, both at 37 degrees C, the Serény test in guinea-pigs and the detection of heat-stable enterotoxin (ST) by the rabbit ileal loop test, the ligated intestine test in pigs and the infant mouse system. Seven of the 14 strains of Yersinia were positive for one or more of these tests. Six of nine strains of Y. enterocolitica and one of four Y. intermedia were positive in one or more tests. The only strain of Y. frederiksenii isolated was negative in all six test systems. All three strains of Y. enterocolitica, serotype 0:8 and the only serotype 0:3 isolated were positive in one or more tests. However, only two of five strains of Y. enterocolitica serotype 0:12, 26, the most frequently encountered, were positive. A good correlation was observed between test results of calcium dependency, autoagglutination and Serény assays. The results indicate that cattle and pigs have the potential to transmit virulent strains of Y. enterocolitica to human beings in Nigeria.  相似文献   

11.
The distribution and persistence of pathogenic, virF/lcrF-positive Yersinia pseudotuberculosis were investigated in pigs and in the pig house environment during rearing to determine possible contamination routes of early infections. Based on Y. pseudotuberculosis-positive tonsils of slaughter pigs in our previous study, Y. pseudotuberculosis-positive animals were traced back to the farms. Eight farms were visited from 6-10 months later, and a total of 155 pooled and six individual faecal samples from pigs and 116 pooled environmental samples were collected for analysis by different culture methods. Four of the eight farms were found to be Y. pseudotuberculosis-positive. All positive faecal samples were obtained from fattening pigs, with prevalence varying from 5% to 71% on positive farms. Sows, boars and suckling piglets were Y. pseudotuberculosis-negative on all farms. Most Y. pseudotuberculosis-positive farms (three of four) were on a one-site production system, which had a higher prevalence of Y. pseudotuberculosis (5-26%) among fattening pigs than the all-in, all-out system (1-5%). All Y. pseudotuberculosis isolates belonged to serotype O:3 and carried the virF/lcrF gene on the virulence plasmid. Biotypes 2 and 3 were involved, the latter in one isolate and not being previously reported in pigs. Altogether 53 isolates from 16 positive samples were characterized with pulsed-field gel electrophoresis (PFGE). Using SpeI, NotI and XbaI enzymes, four, three and two different PFGE patterns were obtained respectively. A total of nine different genotypes were identified when the profiles of the enzymes were combined. The most common genotypes were gIV, found on three, and gXII, found on two of the four Y. pseudotuberculosis-positive farms. The same genotypes previously detected in pig tonsils were present in pig faeces from the same farm, indicating that some Y. pseudotuberculosis strains can persist in the pig house environment.  相似文献   

12.
The aim of this research was to describe two fatal cases of Yersinia enterocolitica bioserotype 4/O:3 infection in non-human primates and to characterise the isolates by PCR and PFGE. In July 2004, two marmosets (Callitrix jacchuss) born in captivity in Zagreb Zoo, died following a few days of intermittent diarrhoea in intervals of 2 weeks. The pathomorphological diagnosis of the female (born in 1997) and the male (born in 1995) marmoset, was disseminated miliary necrosis of the liver. Y. enterocolitica 4/O:3 was isolated from both livers showing that monkeys are susceptible to this bioserotype. The ail gene, which is an essential chromosomal virulence factor in pathogenic Y. enterocolitica isolates, was present in the marmoset isolates. Two different PFGE patterns were obtained from the isolates of the male liver with NotI enzyme. One genotype of the male marmoset isolate was indistinguishable from the genotype of the female marmoset isolate when NotI, ApaI and XhoI enzymes were used indicating a common infection source for the marmosets. The genotypes of the marmoset isolates differed only slightly from one human (of seven Croatian isolates) and from one pig isolate (representing a common genotype found among human and porcine isolates in Germany) suggesting that raw pork fed to the marmoset could have been the infection source.  相似文献   

13.
Outer membrane proteins (OMPs) are the major virulent factors of Haemophilus parasuis. PCR-RFLP targeting the ompA gene was conducted to investigate the possibility of genotyping H. parasuis in this study. Fifteen reference strains and 49 isolates from pig farms in northwest China were genotyped by PCR-RFLP with a pair of specific primers. The results indicated that both the 15 reference strains and 49 isolates could be classified into 8 different genotypes by PCR-RFLP, respectively. Seven genotypes including AA, BB, BA, CA, BC, BD and CD existed simultaneously in the reference strains and isolates, but genotype CB only existed in the isolated strains. Interestingly, genotypes BA, CD and CA were only found in diseased pigs and accounted for 38.8%, 22.4% and 18.4% of the isolates, respectively. On the other hand, strains isolated from apparently healthy pigs were classified into genotypes AA, BB, BC and CB. However, the virulent reference serovar 1 strain has an AA genotype, and the fact that nearly all strains from the healthy pigs belonged to serovars classed as virulent suggests that these genotypes might also include virulent strains; therefore, further validation with more field strains is needed. The capability of the RFLP-PCR method based on the ompA gene for genotyping H. parasuis isolates indicates that this method may be a useful tool for epidemiological study.  相似文献   

14.
The objectives of this study were the identification of the different contamination sources of Yersinia enterocolitica, as well as the determination of the prevalence and the distribution of the different genotypes in swine herds. The owners of 20 farms, located in the Richelieu-Yamaska region, agreed to participate in the study. Each farm was visited a minimum of 5 times between May and October 1997, and, at each visit, 20 environmental and 10 fecal samples were collected. Yersinia enterocolitica isolates were identified, serotyped, and submitted to a genetic characterization by pulsed-field gel electrophoresis. The correlation coefficient (0.61) between prevalence in environment and in feces was significant (P = 0.004). Among the 153 positive samples, 93.5% belonged to serotype 0:3. The comparison of PFGE profiles revealed that all environmental Y. enterocolitica isolates had a profile identical to that of isolates recovered in feces from the corresponding farms. Also, when the genetic profiles of isolates recovered from feces collected at the first visit were compared with the profiles of isolates obtained from the subsequent visits, the same profile was observed on every farm. We concluded that environment does not represent the main source of contamination of swine by Y. enterocolitica and that, in most instances, the same strain persists in a barn from one production lot to another.  相似文献   

15.
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16.
中国东南部地区副猪嗜血杆菌分离株ERIC-PCR指纹图谱分析   总被引：2，自引：0，他引：2  
采用肠杆菌基因间重复一致序列PCR方法,在对15种副猪嗜血杆菌血清型参考株鉴定获得15种不同ERIC-PCR指纹的基础上,对分离自中国东南部发生Glasser's病的不同猪场的111株副猪嗜血杆茵进行了指纹鉴定.结果显示:111株分离株显示出23种指纹图谱,前3种最流行的指纹图谱为ERIC-PCR X X(20/111),X X ⅢⅠ(9/111)和Ⅳ(8/111).且在111株分离株中,来自不同地区的分离株分别表现出不同种类的指纹图谱.该试验表明,ERIC-PCR方法可适用于对某一地区的副猪嗜血杆菌进行分子流行病学的研究和基因型的鉴定;试验结果还揭示了副猪嗜血杆茵在中国东南部地区已广泛存在并具有多样的基因型.  相似文献   

17.
In this study, 117 isolates of Haemophilus parasuis from organs and tissues from pigs showing clinical signs, were characterised and compared with 10 H. parasuis reference strains. The isolates were subjected to the 16S rRNA gene PCR and subsequently serotyped, genotyped by 60-kDa heat shock protein (Hsp60) gene sequences, the enterobacterial repetitive intergenic consensus (ERIC) PCR and a multiplex PCR for the detection of the vtaA virulence associated trimeric autotransporter genes. Serotyping revealed the presence of 13 H. parasuis serovars. Serovars 3 and 10 were not detected, and 16 of the 117 H. parasuis isolates could not be typed by specific antisera. All isolates were positive in the 16S rRNA gene specific H. parasuis PCR. ERIC-PCR revealed a very heterogeneous pattern with 61 clusters; based on a 90% agreement. In total, 46 different Hsp60 sequence types were detected. Using 98% sequence similarity, as threshold for separation, 22 separate Hsp60 sequence clusters were distinguished. There was no correlation between H. parasuis serovars and ERIC-PCR clusters or Hsp60 sequence types, but both the ERIC-PCR and the Hsp60 sequence typing are suited as markers for H. parasuis molecular-epidemiology studies. In total, 102 H. parasuis swine isolates corresponded to the virulence associated group 1 vtaA type. The group 1 vtaA was detected in 12 different serovars. Only four of the 46 Hsp60 sequence types were not associated with the group 1 vtaA. This study shows that Dutch H. parasuis isolates from pigs with clinical signs have both a high serovar and genotypic lineage diversity. A majority of the known serovars contain the group 1 vtaA.  相似文献   

18.
From 2005 to 2007, Mycobacterium tuberculosis complex (MTC) strains were isolated from cattle, goats and pigs samples collected at the Bodija abattoir and from human samples from tuberculosis patients and livestock traders at the Akinyele cattle market in Ibadan, Southwestern Nigeria. Seventy four isolates obtained from humans (24) and livestock (50) were identified as MTC strains. Thirty two isolates were spoligotyped. Nineteen of these 32 isolates were identified as M. tuberculosis whilst 13 were identified as Mycobacterium bovis. M. bovis was isolated from two humans, whereas M. tuberculosis was isolated from a bovine, a pig and a goat. All the M. bovis isolates identified in this study belonged to the Africa 1 clonal complex. Multiple locus VNTR [variable number of tandem repeats] analysis (MLVA) was carried out on the 74 isolates. Three major clusters were defined. Group A consisted of 24 M. tuberculosis isolates (MLVA genotypes 1-18). One strain was isolated from a bovine and one from a pig. Group B consisted of 49 M. bovis strains (MLVA genotypes 19-48), mainly of cattle origin but also included four goat, nine pig and two human isolates. Group C consisted of a single M. tuberculosis isolate (MLVA genotype 49) obtained from a goat. Spoligotyping and MLVA confirmed it as clustering with the East Africa Indian clade found in humans in Sudan and the Republic of Djibouti. The isolation of three M. tuberculosis strains from livestock raises the question of their epidemiological importance as a source of infection for humans.  相似文献   

19.
Thirty‐one Salmonella Enteritidis strains isolated from chickens, broilers and hens were analysed by genotypic typing including REP‐PCR, ERIC‐PCR and ITS profiling (PCR‐ribotyping). Analysis of DNA banding patterns generated by REP‐PCR revealed the presence of 22 different genotypes, which were grouped by dendrogram analysis into three distinct lineages (maximum similarity approx. 50%). Each isolate of S. Enteritidis analysed by ERIC‐PCR generated an individual DNA pattern. Again, these isolates could be divided into three distinct genomic groups (maximum similarity approx. 60%) by their ERIC‐PCR fingerprints. REP‐ and ERIC‐PCR were found to be more discriminatory for typing of S. Enteritidis than ITS profiling. Amplification of the 16S‐23S rDNA spacer region gave nine different profiles of DNA, subdivided into two closely related groups by dendrogram analysis. In summary, data obtained by genotyping methods for S. Enteritidis isolates from regions located in the south‐west and the central parts of Poland revealed an enormous heterogeneity among analysed samples, and proved that REP‐ and ERIC‐PCR are highly discriminatory techniques, which can be used, in addition to conventional methods, in epidemiological studies of S. Enteritidis infections.  相似文献   

20.
To compare the genotypes of Campylobacter jejuni, isolates of cattle origin were collected from 9 Polish farms and genotyped by ERIC-PCR. We identified 28 genotypes among the 43 C. jejuni isolates, and demonstrated high genomic diversity. The highest level of diversity was observed in strains isolated from stanchion-barn animals in opposition to those from the loose-housing system.  相似文献   

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