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1.
Pulsed‐field gel electrophoresis (PFGE) and random amplified polymorphic DNA (RAPD) analysis were used to compare 21 Mycoplasma gallisepticum strains and five M. imitans strains. Each strain of M. gallisepticum typed by PFGE and RAPD methods was genetically quite unique and RAPD and PFGE fingerprinting enabled strain characterization. Relationships between the M. gallisepticum and M. imitans strains were established and dendrograms were drawn from PFGE and RAPD patterns. PFGE group A and RAPD group D were significantly associated with M. imitans strains (P < 0.05). Three M. imitans strains shared the same PFGE and RAPD patterns. The two M. gallisepticum vaccine strains had singular PFGE and RAPD patterns. Thus, PFGE and RAPD can be used to investigate disease outbreaks in vaccinated flocks or for epidemiological tracking. For M. gallisepticum, the RAPD and PFGE discriminatory powers were superior to 0.95 and the in vitro, in ovo and in vivo reproducibility of RAPD and PFGE was 100%. The RAPD drawback was the inconsistent band intensity complicating the interpretation of patterns, while the PFGE limit was its low typeability (86%). Thus, these two molecular typing methods seemed complementary for M. gallisepticum epidemiological studies.  相似文献   

2.
Molecular investigation of 16 strains, conventionally identified to be Malassezia pachydermatis, isolated from dogs in Japan was carried out by random amplification of polymorphic DNA (RAPD) and chitin synthase 2 (CHS2) gene sequence analyses. The RAPD band patterns of 13 clinical isolates were identical to that of standard strain of M. pachydermatis (CBS-1879). The other three clinical isolates were different from the standard strain of M. pachydermatis in RAPD patterns, and two of the three isolates were identical. About 620 bp genomic DNA fragments of the CHS2 gene were amplified from the same 16 clinical isolates of M. pachydermatis by polymerase chain reaction (PCR) and sequenced. The phylogenetic analysis of the nucleotide sequences of CHS2 gene fragments of the 16 clinical isolates revealed that the 13 strains were genetically very close to the standard strain of M. pachydermatis and the other two isolates were genetically close to the standard strain of M. furfur rather than M. pachydermatis. The remaining one isolate was phylogenetically distinct from all the seven Malassezia species reported so far.  相似文献   

3.
Mycoplasma ovipneumoniae is one of only two mycoplasma species associated with small ruminant disease in Britain and has been associated with an increasing number of disease outbreaks since 2002. This investigation used well-defined techniques to assess the variability of UK M. ovipneumoniae isolates, in an attempt to identify strain clusters within the population. Strains received for routine diagnosis between 2002 and 2004 were analysed using random amplified polymorphic DNA (RAPD) and pulsed field gel electrophoresis (PFGE). Of the 43 samples screened 40 RAPD Hum-1, 41 RAPD Hum-4 and 40 PFGE profiles were observed. Composite data analysis divided strains into 10 similarity clusters with SDS-PAGE and Western blotting indicating that this DNA variability is translated into a pattern of variable protein expression. In order to assess the strains isolated within flocks two sets of samples, from diverse locations, were included in this test panel. The presence of variable isolates existing on the same farm may reflect animal movement and the introduction of asymptomatic, carrier, animals where M. ovipneumoniae is already established within a flock. These findings have significant implications regarding disease diagnosis and management.  相似文献   

4.
OBJECTIVE: To compare molecular typing methods for the differentiation of Salmonella enterica serovar Enteritidis phage type (PT) 4 isolates that allowed for the determination of their genetic relatedness. SAMPLE POPULATION: 27 Salmonella Enteritidis PT 4 strains isolated in the United States and Europe. PROCEDURE: Several molecular typing methods were performed to assess their ability to genetically differentiate among Salmonella Enteritidis PT 4 isolates. Results of pulse-field gel electrophoresis (PFGE), repetitive polymerase chain reaction (PCR) assay, 16S rRNA gene sequencing, random amplification of polymorphic DNA (RAPD), PCR-restriction fragment length polymorphism of 16S rRNA, and antimicrobial susceptibility were evaluated. RESULTS: Compared with results for other techniques, results for the RAPD typing method with the RAPD1 primer reveal that it was the most discriminatory fingerprinting technique, and it allowed us to cluster Salmonella Enteritidis PT 4 isolates on the basis of their genetic similarity. CONCLUSIONS AND CLINICAL RELEVANCE: This study revealed the value of RAPD with the RAPD1 primer as a tool for epidemiologic investigations of Salmonella Enteritidis PT 4. It can be used in conjunction with PFGE and phage typing to determine the genetic relatedness of Salmonella Enteritidis isolates involved in outbreaks of disease. A reliable and highly discriminatory method for epidemiologic investigations is critical to allow investigators to identify the source of infections and consequently prevent the spread of Salmonella Enteritidis PT 4.  相似文献   

5.
A high proportion of dogs suffer from respiratory disease when they are placed in kennels for vacation or re-homing. The role of Mycoplasma cynos as an initiating agent in canine infectious respiratory disease was investigated by examining the serological response of dogs to this organism at the time of entry into a large re-homing kennel. Forty-two paired serum samples from dogs (21-day interval) were examined for antibody to M. cynos using Western blotting. The development of antibody in the serum was related to clinical disease recorded over the same period. Sixty seven per cent of the dogs showed a two-fold or greater rise in antibody to M. cynos during the first 3 weeks in the kennel. Reactivity with a 45 kDa antigen was dominant. Of those showing a positive serological reaction, 80% had recorded clinical respiratory disease while 20% remained healthy. The findings of this study show that an antibody response to M. cynos is common in dogs entering the re-homing kennel and is positively related to the development of clinical respiratory disease.  相似文献   

6.
Although the dog breeding industry is common in many countries, the presence of antimicrobial resistant bacteria among pups in kennels has been infrequently investigated. This study was conducted to better understand the epidemiology of antimicrobial-resistant Escherichia coli isolates from kennel pups not treated with antimicrobials. We investigated susceptibilities to 11 antimicrobials, and prevalence of extended-spectrum β-lactamase (ESBL) in 86 faecal E. coli isolates from 43 pups in two kennels. Genetic relatedness among all isolates was assessed using pulsed-field gel electrophoresis (PFGE). Susceptibility tests revealed that 76% of the isolates were resistant to one or more of tested antimicrobials, with resistance to dihydrostreptomycin most frequently encountered (66.3%) followed by ampicillin (60.5%), trimethoprim-sulfamethoxazole (41.9%), oxytetracycline (26.7%), and chloramphenicol (26.7%). Multidrug resistance, defined as resistance against two or more classes of antimicrobials, was observed in 52 (60.5%) isolates. Three pups in one kennel harboured SHV-12 ESBL-producing isolates. A comparison between the two kennels showed that frequencies of resistance against seven antimicrobials and the variation in resistant phenotypes differed significantly. Analysis by PFGE revealed that clone sharing rates among pups of the same litters were not significantly different in both kennels (64.0% vs. 88.9%), whereas the rates among pups from different litters were significantly different between the two kennels (72.0% vs. 33.3%, P < 0.05). The pups in the two kennels had antimicrobial-resistant E. coli clones, including multidrug-resistant and ESBL-producing clones. It is likely that resistant and susceptible bacteria can clonally spread among the same and/or different litters thus affecting the resistance prevalence.  相似文献   

7.
Forty-four Actinobacillus pleuropneumoniae isolates recovered from both healthy and diseased pigs were characterized by random amplified polymorphic DNA analysis (RAPD), pulsed field gel electrophoresis (PFGE) and apx toxin gene typing. Nine RAPD types and 14 PFGE patterns were identified. No common RAPD or PFGE patterns were found between strains of serotype 1 and those of serotype 5. The RAPD analysis indicated that the 15 serotype 1 strains isolated from diseased pigs were assigned to 4 RAPD types, with 66% of strains characterized by the same RAPD type. By contrast, the 5 strains of serotype 1 isolated from healthy carriers were dispersed in 4 RAPD types. These data suggest that the diversity of strains isolated from healthy pigs could be higher than that of strains recovered from diseased pigs. In addition, all serotype 5 strains exhibited a unique RAPD type. Unlike RAPD, PFGE analysis allowed discrimination among isolates of serotype 1 and among those of serotype 5. All but 3 isolates showed the same apx genotype as their respective serotype reference strain. These data indicate that RAPD analysis is a valuable rapid tool for routine subtyping of strains of serotype 1. For strains of serotype 5, a combination of several typing methods, such as PFGE and apx gene typing, is needed to provide useful information on the molecular epidemiology of swine pleuropneumonia.  相似文献   

8.
OBJECTIVE: To determine whether staphylococcal isolates cultured from pustules and carriage sites in dogs with superficial bacterial folliculitis were genotypically the same strain by use of pulsed-field gel electrophoresis (PFGE). ANIMALS: 40 dogs with superficial bacterial folliculitis. PROCEDURES: Samples were obtained from 3 pustules and 3 carriage sites (anus, axillary skin, and nasal mucosa). Bacterial culture, morphologic identification, Gram staining, catalase and coagulase tests, speciation, and PFGE were performed. RESULTS: Of 246 isolates, 203 were Staphylococcus intermedius, 5 were Staphylococcus aureus, 15 were Staphylococcusspp, and 22 were coagulase-negative staphylococcal isolates. No dog had an isolate with the same PFGE pattern as an isolate from another dog. Coagulase-positive isolates from multiple pustules and multiple carriage sites had the same PFGE pattern in 37 of 39 (94.9%) and 22 of 39 (56.4%) dogs, respectively. Coagulase-positive staphylococcal isolates from at least 1 pustule had the same PFGE pattern as an isolate from at least 1 carriage site in 34 of 36 (94.4%) dogs. Ninety-seven of 116 (83.6%) coagulase-positive staphylococcal isolates from pustules had the same PFGE pattern as an isolate from at least 1 carriage site. Sixty-nine of 91 (75.8%) coagulase-positive staphylococcal isolates from carriage sites had the same PFGE pattern as an isolate from at least 1 pustule. CONCLUSIONS AND CLINICAL RELEVANCE: Coagulasepositive staphylococcal strains were heterogeneous among dogs with superficial bacterial folliculitis. In individual dogs, strains from multiple pustules were genotypically the same, and strains from pustules were genotypically the same as strains from carriage sites.  相似文献   

9.
The degree of genetic diversity in 45 Bordetella (B.) bronchiseptica strains comprised of a vaccine strain (N = 1), reference strains (N = 3) and field isolates (N = 41) was evaluated using random amplified polymorphic DNA (RAPD) fingerprinting and pulsed-field gel electrophoresis (PFGE). Three candidate primers were selected for RAPD analysis after screening 20 random decamer oligonucleotides for their discriminatory abilities. The OPA-07, OPA-08 and OPA-18 primers yielded 10, 10, and 6 distinct fingerprint patterns, respectively. The most common identical RAPD pattern was produced by OPA-07 which was shared by 32 isolates (71.1%), the pattern produced by OPA-08 was shared by 26 isolates (57.8%), and the pattern produced by OPA-18 was shared by 40 isolates (88.9%). The RAPD patterns of the vaccine strain and the 3 reference strains did not match any of the patterns produced by the field isolates when primers OPA-07 and OPA-08 were used. PFGE using the restriction endonuclease XbaI produced a total of 15 patterns consisting of 4 PFGE types (A, B, B1 and C, differing by ≥ 4 bands) and 11 A subtypes (differing by ≤ 3 bands). Most of the field isolates exhibited identical type A and B patterns, suggesting that they were related. The vaccine strain and the three reference strains showed different PFGE patterns as compared to the identical type A strains.  相似文献   

10.
The course of enzootic pneumonia, caused by Mycoplasma hyopneumoniae, is strongly influenced by management and housing conditions. Other factors, including differences in virulence between M. hyopneumoniae strains, may also be involved. The aim of this study was to evaluate the virulence of six M. hyopneumoniae field isolates and link it to genetic differences as determined by randomly amplified polymorphic DNA (RAPD) analysis. Ninety, conventional M. hyopneumoniae-free piglets were inoculated intratracheally with the field isolates, a virulent reference strain or sterile culture medium. Animals were examined daily for the presence of disease signs and a respiratory disease score (RDS) was assessed per pig. Twenty-eight days post infection, pigs were euthanized, blood sampled and a lung lesion score was given. Lung samples were processed for histopathology, immunofluorescence testing for M. hyopneumoniae and isolation of M. hyopneumoniae. RAPD analysis was performed on all M. hyopneumoniae strains. Significant differences between isolates were found for the RDS, lung lesion score, histopathology, immunofluorescence and serology. Based on the results of the different parameters, isolates were divided into three "virulence" groups: low, moderately and highly virulent strains. Typically, a 5000 bp RAPD fragment was associated with the highly and moderately virulent strains whereas it was absent in low virulent strains. It was concluded that high variation in virulence exists between M. hyopneumoniae strains isolated from different swine herds. Further studies are required to determine whether the 5000 bp fragment obtained in the RAPD analysis can be used as a virulence marker.  相似文献   

11.
Popular sires, a limited population size, and the founder event are widely considered the main reasons for the low genetic diversity observed in many dog breeds. However, these factors have had only a small role in the historic decrease in diversity observed in the Norfolk Terrier breed. We show that the decrease in this breed has been mainly due to large, popular kennels. Dogs from these kennels have, on average, larger genetic contributions to subsequent generations than others. A test for the presence of a popular kennel effect is proposed and applied (P < 0.001). These kennels were found to be the same as nuclei of selection existing in other livestock species. This result revealed a hierarchical structure of dog breeding schemes, with an asymmetric gene flow predominantly from the nuclei toward the main population. Possible reasons for this structure and implications for future population management are discussed. The main reason is probably that the breed type was established by large, popular kennels and that small kennel breeders used their stud dogs to benefit from the achievements of the popular kennels. Many kennels, however, were unable to make their own substantial genetic contributions to the breed.  相似文献   

12.
Mycoplasma bovis is a major cause of respiratory outbreaks in cattle feedlots. In this study pulsed-field gel electrophoresis (PFGE) was used to trace field strains and provide information on M. bovis patterns of spread in calf feedlots. The suitability of KpnI, MluI and SmaI restriction enzymes was assessed on different sets of strains. The discriminative power of the first two enzymes was first assessed using 28 epidemiologically unrelated strains; stability was 100% on multiple isolates from in vivo experimental infection. Thirty-nine field isolates from six feedlots were then evaluated. In contrast to the unique fingerprints displayed by the unrelated strains, the isolates from the feedlots showed identical patterns at the time of the outbreak of respiratory disease and 4 weeks later. The PFGE typing results suggest that M. bovis strains follow a clonal epidemic spread pattern at the herd level and that the same strain persists in calves of the herd after the clinical signs have disappeared.  相似文献   

13.
"Kennel cough" in dogs in animal shelters is readily transmissible, reduces adoption rates, and commonly leads to the euthanasia of affected dogs. In cats, tracheobronchitis, conjunctivitis, and pneumonia have been associated with Bordetella bronchiseptica infection-but most cases of upper-respiratory infection (URI) probably are caused by herpesvirus and calicivirus, and many B. bronchiseptica culture-positive cats are clinically normal. Our prospective observational study was undertaken to document the contribution of B. bronchiseptica to disease in cats and dogs from two animal shelters undergoing outbreaks of canine kennel cough, to evaluate whether cross-species transmission might have occurred, and to determine if the presence of infected cats represented a risk to dogs. Clinically defined cases of kennel cough in dogs and URI in cats were investigated in two shelters by calculating clinical-disease incidence, alveolar-lavage cytological examination, bacterial and viral cultures, antibiotic-susceptibility testing, and molecular fingerprinting by pulsed-field gel electrophoresis.In a 40-cat and 40-dog "no-kill" shelter, the prevalences of culture positivity were 47% for B. bronchiseptica and 36% for calicivirus at the same time as two resident dogs demonstrated clinical cough. When no dogs had kennel cough 3 months later, 10% of cats were B. bronchiseptica-culture-positive and 63% calicivirus positive. In a large traditional shelter, the incidence of kennel cough in dogs increased over 12 weeks to a maximum of 19 cases/week/120 dogs, during which time the culture prevalence was 23% for B. bronchiseptica in dogs and 47% in cats. Three to 6 months before the kennel-cough epidemic, no dogs or cats were B. bronchiseptica positive. Very little genetic variability was detected in isolates from these shelters; all isolates except one corresponded to a single strain type which was identical to the pattern in a vaccine used in these shelters. Isolates from other cats, a horse, a llama, and a sea otter were genetically distinct from the shelter isolates. There was widespread resistance to cephalosporins and ampicillin, but low or no resistance to amoxicillin/clavulanate, trimethoprim-sulfamethoxazole, tetracycline, and enrofloxacin. Greater percent resistance was observed in the traditional shelter than in the no-kill shelter and feline isolates were more likely to be resistant than canine isolates.  相似文献   

14.
Strongyloides stercoralis is an intestinal nematode with worldwide distribution, particularly in tropical and subtropical regions. Due to the low sensitivity of traditional parasitological methods, the detection of serum specific antibodies may serve as an alternative test for the diagnosis. The aims of the present study were to verify the occurrence of S. stercoralis and the presence of specific IgG antibodies to the parasite in kennel dogs and keepers, using parasitological and serological assays. A total of 181 dogs were examined from 7 breeding kennels in the city of Uberlandia, southeastern region of Brazil and distributed as follows: kennel A (n=41), kennel B (n=16), kennel C (n=11), kennel D (n=63), kennel E (n=11), kennel F (n=18) and kennel G (n=21). Fecal and serum samples from 11 keepers responsible for kennel cleaning and dog control were also collected in five of the seven kennels (two from kennel A, one from kennel B, four from kennel D, two from kennel E and two from kennel G). Overall, enteroparasites were detected by parasitological assays in 66, 36.5% (95% CI: 2.5-43.4%) of the 181 dogs tested. Only one (0.6%) dog was copropositive for S. stercoralis. Among the keepers only one fecal sample, 9.1% (95% CI: 8.6-9.4%) was positive for hookworm by the Lutz method. Serological assays showed that 44 (24.3%) of the 181 dogs were seropositive for S. stercoralis in at least one of the tests in the following kennels: 21 (11.6%) in kennel A; 1 (0.6%) in kennel B; 5 (2.7%) in kennel C; 6 (3.3%) in kennel D; 1 (0.6%) in kennel E; 9 (4.9%) in kennel F and 1 (0.6%) in kennel G. Among the keepers no S. stercoralis seropositive samples were identified using IFAT but 2 (18.2%) of the keepers from kennel D and 1 (9.1%) from kennel G were seropositive by ELISA. The present study demonstrated that the occurrence of S. stercoralis infection in kennel dogs and keepers is low in the city of Uberlandia and that serological assays can contribute to the diagnosis of canine as well as human strongyloidiasis.  相似文献   

15.
In the present study, 27 primers were screened under different cycles by random amplified polymorphic DNA (RAPD) method. Mathematical models were used for analysis of the genetic relationships among strains, including vaccinal, reference strains and nine field isolates previously characterized as Mycoplasma gallisepticum (MG)F by RAPD and pulsed field gel electrophoresis (PFGE). The PFGE was considered as laborious, expensive and time-consuming than RAPD method. These methods improved the typeability for epidemiological studies of MG with regard to differentiation from vaccinal and field strains.  相似文献   

16.
We evaluated the random amplified polymorphic DNA (RAPD) and pulsed-field gel electrophoresis (PFGE) techniques for studying an outbreak of beta-haemolytic streptococci group A (GAS) occurred at two maternity wards at Danderyd hospital, Stockholm, Sweden. All the isolates were of T-type 8,25. The RAPD technique revealed that all RAPD-PCR profiles were identical. PFGE showed that all the patterns but one were identical. These patterns were compared with 10 different T-type GAS from the strain collection of the Swedish Institute for Infectious Disease Control (SMI) and T-type 8,25 from different years and locations. The SMI strains exhibited patterns different from each other and all different from the isolates from Danderyd hospital. Moreover, RAPD could not differentiate among the T-type 8,25 isolates from different years and locations but PFGE showed differences among the amplicons. Our results indicated that the RAPD and PFGE techniques could be efficient tools in epidemiological studies of GAS.  相似文献   

17.
Caseous lymphadenitis (CLA) is a chronic, suppurative disease, with a worldwide distribution, caused by Corynebacterium pseudotuberculosis. The clinical manifestation of CLA is known to vary between different countries, and has been postulated to be due to differences in the strains present in these countries. Forty-two sheep and goat isolates of C. pseudotuberculosis from Australia, Canada, Eire, The Netherlands and Northern Ireland were characterized by pulsed-field gel electrophoresis (PFGE), biotyping, antimicrobial susceptibility, and production of phospholipase D. The PFGE-determined genotypes of this multicentric collection were then compared with representative ovine and caprine isolates from a previously published panel of PFGE profiles of United Kingdom isolates. Digestion with SfiI generated 16-18 bands in the 48.5 and 290 kb range, and differentiated four distinct pulsotypes amongst the 36 ovine and 6 caprine strains which displayed remarkable homogeneity. Based on these results, it would appear that the genome of C. pseudotuberculosis is highly conserved, irrespective of the country of strain origin.  相似文献   

18.
The molecular epidemiology of Pasteurella multocida has rarely been studied at the farm level in cattle. The aim of this study was to determine whether single or multiple strains of P. multocida tend to exist within farms. Molecular characterisation was carried out on isolates obtained from nasal swabs from 105 calves from 32 randomly selected beef and dairy farms located throughout Scotland, and from 131 calves from 20 farms in the Mayenne region of France, where sampling occurred in response to respiratory disease outbreaks. P. multocida isolates were characterised by random-amplified polymorphic DNA (RAPD) typing and pulsed-field gel electrophoresis (PFGE) using restriction enzyme ApaI. In addition, isolates representative of each farm/RAPD profile combination were typed by multilocus sequence typing (MLST). Among 105 Scottish isolates, 15 RAPD profiles were distinguished. The majority of farms (27/32) had indistinguishable profiles in all positive animals. Five farms had two profiles. Among 140 French isolates, 23 RAPD profiles were distinguished. More within-farm heterogeneity was observed although 10/20 farms had just one profile (E4) in sampled calves. Profile E4 accounted for 60% (84/140) of French isolates. PFGE was more discriminatory than RAPD but confirmed results with respect to within farm homogeneity or heterogeneity of strains, whereas MLST was not discriminatory enough for farm level epidemiology. As in other host species, either several strains or one dominant strain of P. multocida may exist within farms, with evidence for a role of management factors such as movements onto the farm in the number of strains detected.  相似文献   

19.
Neff C  Sudler C  Hoop RK 《Avian diseases》2008,52(2):278-283
Infectious laryngotracheitis is a dramatic disease of the upper respiratory tract in poultry caused by a herpesvirus. In this study we investigated the characteristics of western European field isolates of infectious laryngotracheitis virus (ILTV) to gain more information on their diversity. The examined 104 isolates, collected from acute outbreaks during the last 35 years, originated from eight different countries: Switzerland (48), Germany (21), Sweden (14), the United Kingdom (9), Italy (5), Belgium (4), Austria (2), and Norway (1). Two vaccines, a chicken embryo origin product and a tissue culture origin product, were included in the survey. Polymerase chain reaction (PCR) was performed to amplify a 2.1-kb DNA fragment of ILTV using primers generated for the thymidine kinase (TK) gene. After digestion of the resulting PCR products by restriction endonuclease HaeIII, restriction fragment length polymorphism analysis was carried out. PCR amplicons of three field isolates and both vaccine strains were selected for sequencing. Here 98 field isolates showed the same cleavage pattern and were identical to both vaccine strains (clone 1). They differed from five Swiss isolates with identical cleavage pattern (clone 2) and one Swedish isolate (clone 3). The present study demonstrated that at least three clones of ILTV have been circulating in western Europe during the last 35 years. The 104 isolates analyzed showed a high genetic similarity regarding the TK gene, and a large majority of the field isolates (98/104) were genetically related to the vaccine strains.  相似文献   

20.
Salmonella gallinarum is gram-negative bacteria that cause fowl typhoid (FT) in chickens. Since the first outbreak of FT reported in 1992 in Korea, it has widely spread throughout the country. Today, FT is one of the most devastating diseases of poultry. The aim of the present study was to ascertain a genetic relationship among S. gallinarum isolates collected from different regions of Korea over a 10-year period. We examined a total of 38 isolates of S. gallinarum obtained in 29 regions of Korea from 1992 to 2001 including the 9R vaccine strain and the standard strain of S. gallinarum (ATCC 9184). The PFGE profiles produced 12 different patterns with the XbaI-digestion and 11 different patterns with the SpeI-digestion. The RAPD using URP-6 primers showed eight different genotypes with the same Salmonella isolates. The PFGE patterns of the 9R vaccine strain and ATCC 9184 of S. gallinarum were different from the identical type A, the most common genotype among field isolates in our study. In conclusion, a low genetic heterogeneity was observed among Korean S. gallinarum isolates. In addition, PFGE appeared to be a more accurate and reproducible method for genotyping of S. gallinarum isolates than RAPD.  相似文献   

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