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1.
Rhodococcus equi has been isolated from the submaxillary lymph nodes of domesticated pigs, but little is known about the presence of R. equi in wild boars. The aim of the study was the evaluation of the incidence of R. equi in wild boars and the characterisation of them. Of 482 submaxillary lymph nodes of wild boars shot in 39 settlements throughout Hungary, R. equi was isolated from 60 specimens, and plasmid types of 82 isolates were examined. The isolates were tested for the presence of 15-17-kDa (VapA) and 20-kDa virulence-associated protein antigen (VapB) genes by polymerase chain reaction (PCR). Plasmid DNAs were isolated and analysed by digestion with restriction endonucleases to estimate size and compare their polymorphisms. None of the 82 isolates contained vapA gene but 21 isolates (25.6%) were positive for vapB gene showing 827bp product of the expected size in the PCR amplification. Sixty-one strains (74.4%) did not contain plasmid. The 21 isolates of intermediate virulence contained virulence plasmids that were identified as types 1 (1 isolate), 5 (16 isolates), 21 (1 isolate), and three new distinct plasmid variants (1-1-1 isolate), respectively. On the basis of restriction digestion patterns of plasmid DNAs, we tentatively designated the new variants as types 25-27, respectively. The prevalence of R. equi strains of intermediate virulence among the isolates originated from the submaxillary lymph nodes of wild boars (25.6%) is very similar to those of domestic pigs (26.8%) in Hungary, and plasmid type 5 is the predominating one in both groups. This is the first report of isolation of VapB-positive R. equi from wild boars in the world.  相似文献   

2.
Granulomatous lesions in bovine and especially swine lymph nodes are still frequently observed during routine veterinary meat inspections even though Mycobacterium bovis infections are no longer detected in domestic animals in Slovenia. Different lymph nodes of pigs (n = 260) were investigated using classical bacteriological and molecular methods. Mycobacterium avium alone was isolated in 47.3% of pigs and in mixed infection with Rhodococcus equi in 3.9% of pigs. R. equi alone was isolated in 27.3% and in mixed infection with mycobacteria other than M. avium in 1.5% of pigs. A total of 133 M. avium isolates were typed using the IS1245, IS901 and FR300 PCR. Almost two thirds (60.9%) of isolates belonged to M. avium hominissuis (IS901-, IS1245+ genotype), 33.8% of isolates belonged to M. avium avium (IS901+, IS1245+ genotype) and 5.3% of isolates remained non-typed. Fifty out of 85 R. equi isolates were tested for the virulence-associated antigens (VapA and VapB). Nearly two thirds (60.0%) were positive for VapB while all the other isolates were VapA- and VapB-negative.  相似文献   

3.
Lesions histologically similar to those of natural caseous lymphadenitis developed in sheep popliteal lymph nodes following injection of viable Corynebacterium ovis cells into afferent lymphatic ducts. Histopathological examination of affected lymph nodes suggested that exotoxin might be involved in the establishment, progressive development and persistence of caseous lymphadenitis lesions through localised cytotoxicity.  相似文献   

4.
Pathogenesis of caseous lymphadenitis in sheep and goats   总被引:7,自引:0,他引:7  
The progress of caseous lymphadenitis in sheep and goats is described as involving primary wound infection, lymphatic and haematogenous dissemination, and secondary infection of lymph nodes and various visceral organs. This is followed by elimination or containment of infection, the latter being represented by the characteristic caseous lesions. Resistance to infection is complex involving components of both the specific and non-specific host response. The role of these in pathogenesis is discussed. Bacterial factors including the phospholipase exotoxin and cytotoxic lipid contribute to pathogenesis at a local level with little likelihood of systemic effect in the natural disease. In a disease such as caseous lymphadenitis, lesion site, size or number do not indicate severity of disease but rather, reflect the ability of the host to mount a cellular response to infection.  相似文献   

5.
The virulence genes and plasmid profiles of 23 Rhodococcus equi isolates from 258 lymph nodes from domestic pigs (129 nodes with lesions and 129 without lesions) and 120 lymph nodes from slaughtered wild boars (60 nodes with lesions and 60 without) were characterized. R. equi was obtained from 19 lymph nodes of domestic pigs, 17 with, and two without lesions, and from four lymph nodes with lesions, from wild boars. The 23 isolates were tested for the presence of vapA and vapB genes, responsible for the 15–17 and 20 kDa virulence-associated proteins, respectively, by PCR in order to characterize as virulent (VapA), intermediately virulent (VapB) and avirulent. Plasmid DNAs were isolated and analyzed by digestion with restriction endonucleases to estimate size and compare their polymorphisms. Of the 19 domestic pigs strains, seven (36.8%) were avirulent and 12 (63.2%) were intermediately virulent, with the intermediately virulent isolates being plasmid types 8 (8 isolates), 10 (2 isolates), 1 (1 isolate) and 29 (1 isolate). The plasmid type of four strains isolated from wild boars was also intermediately virulent type 8. None of the domestic pigs and wild boar isolates showed the vapA gene. These findings demonstrate a high occurrence of plasmid type 8 in isolates from pigs and wild boars, and the similarity of plasmid types in the domestic pigs, wild boars and human isolates in Brazil.  相似文献   

6.
Rhodococcus equi isolates (204) obtained from foals (lung abscesses, lymph nodes, nasal discharge, rectal swabs) bred in 15 studs located throughout Hungary, isolates from soil samples, lymph nodes of pigs and from lesions of human patients were examined to determine genotypic diversity of virulence-associated plasmids. Isolates were tested for the presence of 15-17 kDa virulence-associated protein antigen (VapA) and 20k Da (VapB) genes by polymerase chain reaction (PCR). Plasmid DNAs were isolated and analysed by digestion with restriction endonucleases for estimation of size and comparison of polymorphisms. Of 146 clinical isolates from foals in 15 studs, 129 (88.3%) gave positive results for the VapA gene, showing a 564 bp product of the expected size in the PCR amplification. Of the 129 clinical isolates from foals, 123 contained an 85 kb type I plasmid and the remaining six contained an 87 kb type I plasmid. Of 48 soil isolates from two horse studs, 26 (54.2%) were positive for VapA gene and contained an 85 kb type I plasmid. Of three pig isolates, one was positive for VapA gene and contained an 85 kb type I plasmid, and the remaining two were positive for the VapB gene, showing a 827 bp product of the expected size in the PCR amplification and were R. equi of intermediate virulence which contained a 95 kb type S5 plasmid. Of the seven human isolates, five were positive for VapB gene by PCR, these were R. equi of intermediate virulence, which contained a 95 kb type S5 plasmid. These results revealed that virulent R. equi strains harbouring a virulence plasmid of 85 kb type I or 87 kb type I, which have been found in clinical isolates from Europe and North and South America, are widespread in Hungary. Furthermore, same intermediately virulence plasmid type was found in both human and pig isolates.  相似文献   

7.
A 2‐year‐old Boer doe was presented with respiratory distress and severe inspiratory dyspnea. Cervical and thoracic radiographs revealed a marked retropharyngeal soft tissue mass effect, several mineralized pharyngeal and retropharyngeal structures, and a pulmonary mass. Computed tomography (CT) revealed a severely enlarged right medial retropharyngeal lymph node, which caused laryngeal compression, leading to upper airway obstruction. Multiple cervical and thoracic lymph nodes, and the pulmonary mass had an irregular layered/laminated pattern of mineralization. Imaging findings were consistent with caseous lymphadenitis, and further confirmed with culture, necropsy, and histopathology. This is the first report of CT appearance of caseous lymphadenitis in a goat.  相似文献   

8.
A cat with granulomatous lymphadenitis due to Corynebacterium equi is described. Clinically the cat was diagnosed as having lymphosarcoma. Bacteria were cultured from the lymph nodes.  相似文献   

9.
The relationship between the visceral form of caseous lymphadenitis and a chronic debilitating condition of mature sheep designated as the thin ewe syndrome was investigated. Internal abscesses were found during necropsy in 81% of animals with thin ewe syndrome and Corynebacterium pseudotuberculosis (C ovis) was recovered from 86% of the animals with internal abscesses. Other pyogenic bacteria, including C pyogenes, C equi, Staphylococcus epidermis, S aureus, and Pseudomonas aeruginosa were often recovered in association with C pseudotuberculosis. Moraxella sp was recovered in 41% of the animals with internal abscesses. In some abscesses, Moraxella sp was the dominant microorganism isolated and in others, they were outnumbered only by C pseudotuberculosis. Species isolated included M bovis, M osloensis, and M nonliquefaciens. The potential importance of Moraxella sp to the cause and pathogenesis of the thin ewe syndrome is not known. The results of the present study indicate that visceral caseous lymphadenitis is either an important contributing factor to the development of thin ewe syndrome or that the presence of thin ewe syndrome may predispose affected sheep to the development of visceral caseous lymphadenitis. A skin test reagent prepared by sonicating C pseudotuberculosis was of limited value in detecting animals with visceral caseous lymphadenitis. Only 56% of the animals with abscesses caused by C pseudotuberculosis gave positive delayed-type hypersensitivity skin test responses.  相似文献   

10.
Summary The cervical lymph nodes of pigs, the retropharyngeal and submandibular lymph nodes of cattle and faecal samples from both animal species were examined for the presence of Corynebacterium equi. The organism was recovered from 19 (35 per cent) of 54 porcine cervical lymph nodes and from 0 of 54 bovine retropharyngeal and submandibular lymph nodes. Fifteen (50 per cent) of 30 bovine faecal and 11 (35 per cent) of 31 porcine faecal samples yielded C. equi.  相似文献   

11.
Summary

The cervical lymph nodes of pigs, the retropharyngeal and submandibular lymph nodes of cattle and faecal samples from both animal species were examined for the presence of Corynebacterium equi. The organism was recovered from 19 (35 per cent) of 54 porcine cervical lymph nodes and from 0 of 54 bovine retropharyngeal and submandibular lymph nodes. Fifteen (50 per cent) of 30 bovine faecal and 11 (35 per cent) of 31 porcine faecal samples yielded C. equi.  相似文献   

12.
A double antibody sandwich ELISA developed by ID-DLO, Lelystad to detect Corynebacterium pseudotuberculosis infection was used on 329 sheep from four pedigree Suffolk flocks in which clinical cases of caseous lymphadenitis (CLA) had occurred. At subsequent necropsy, typical CLA lesions were seen in 133 sheep, and the diagnosis was confirmed on culture. Lesions were most commonly seen in lungs (n = 46), parotid lymph nodes (n = 44), prescapular lymph nodes (n = 38) and mediastinal lymph nodes (n = 31). The sensitivity of the ELISA test for detecting culture-positive sheep was 0.88, while the specificity of the test was 0.55. The antibody ELISA detected 87.5 per cent of sheep that had CLA lesions restricted to internal organs only. It was concluded that the ELISA test has a valuable role in detecting sheep with both clinical and subclinical CLA.  相似文献   

13.
Caseous lymphadenitis, caused by Corynebacterium pseudotuberculosis, was studied in ewes to devise a reliable method of induced infection that would help to understand mechanisms by which abscesses develop in lymph nodes or internal organs, especially the lungs. Fifteen adult ewes, from a flock where the occurrence of caseous lymphadenitis was unknown, were inoculated SC in the auricle with various doses of a virulent strain of C pseudotuberculosis. Ewes inoculated with at least 10(8) viable corynebacteria develop a strong local reaction that was apparent 4 hours after challenge exposure and lasted 7 to 14 days. Of these ewes, all developed at least 1 abscess and 3 developed multiple abscesses in lymph nodes draining the inoculated auricle and in the lungs. All infected ewes developed a strong antibody response against C pseudotuberculosis exotoxin, which persisted for 3 months. Of 9 ewes infected with 1.2 X 10(8) corynebacteria, 3 developed lesions because of field strains of C pseudotuberculosis and had an increased capacity to limit the dissemination of challenge-inoculum bacteria by developing only one abscess in the draining lymph node (parotid or prescapular lymph node). Seemingly, inoculation in the external ear was a suitable method for obtaining a reproducible infection and indicated that a primary infection might protect against reinfection by limiting dissemination of C pseudotuberculosis.  相似文献   

14.
The effect of age on susceptibility of young pigs to streptococcic lymphadenitis was investigated. Twenty-nine cesarean-derived, colostrum-deprived pigs were allotted to 7 groups exposed to type IV group E Streptococcus (GES) at 5, 14, 28, 35, 56, 70, and 84 days of age. Four cesarean-derived, colostrum-deprived pigs were maintained as nonexposed controls. Six naturally farrowed, susceptible controls were exposed to GES at 63 to 84 days of age. All exposed pigs were killed and necropsied 28 days after exposure. Lesions of streptococcic lymphadenitis were not observed in pigs exposed at 5 or 14 days of age, except for 1 microabscess in a mandibular lymph node in a pig exposed at 14 days, but GES was recovered from 11% of lymph nodes examined from pigs of those age groups. Lesions and GES-positive lymph nodes were frequent in cesarean-derived, colostrum-deprived pigs exposed at 28 days and older and in susceptible controls. Serologic response to exposure, as determined by microtitration agglutination test and bactericidal test, was observed only in pigs exposed at 14 days and older. The absence of abscess development in pigs exposed at 5 or 14 days of age was not caused by antibody or failure of infecting organisms to reach the target organs.  相似文献   

15.
Concanavalin A (Con A) induced suppressor cell activity was evaluated in a group of ovine progressive pneumonia virus-antibody positive sheep (OPPV+). Decreased levels of suppressor activity were observed in the peripheral blood and regional pulmonary lymph nodes of animals with clinical and pathological evidence of ovine progressive pneumonia (OPP) when compared to animals with no lesions and animals with caseous lymphadenitis involving the lungs and pulmonary lymph nodes. Decreased levels of Con A stimulated lymphocyte proliferation was also observed in the peripheral blood and iliac lymph nodes of sheep with OPP. Sheep with OPP were found to be hypogammaglobulinemic. Sera from OPPV+ sheep had no effect on T and B cell mitogen stimulated responses of lymphocytes from sheep seronegative for antibodies to ovine progressive pneumonia virus (OPPV-) when compared to normal sheep serum.  相似文献   

16.
Streptococcus equi (S. equi) causes equine strangles, a highly contagious and widespread purulent lymphadenitis of the head and neck. Highly resistant to phagocytosis, it produces long extracellular chains in affected lymph nodes. In a screen of clones reactive with convalescent serum from a gene library of S. equi CF32 we identified IdeE, an IgG-endopeptidase and homologue of the leucocyte receptor Mac-1 (CD11b). IdeE is expressed during S. equi infection eliciting both serum and mucosal antibody responses which persisted at significant levels in serum for over 200 days. Release from S. equi into culture medium was detected during the exponential phase of growth. The closely related Streptococcus zooepidemicus appeared to store the protein but not to release it. Antiphagocytic activity for equine neutrophils was dose-dependent and neutralized by IdeE-specific antiserum. Biotinylated IdeE bound weakly to about 77% of purified equine neutrophils and strongly to the remainder.  相似文献   

17.
Among 25,027 slaughter pigs raised in two farms, tuberculous lesions were detected in the lymph nodes of 898 (3.6%) of them. Tuberculous lesions were most commonly found in the mesenteric (601; 2.4%) and head (451; 1.8%) lymph nodes. Mycobacteria were isolated from 49 of 120 randomly selected mesenteric, head and bronchial lymph nodes with diagnosed tuberculosis originating from both farms. Forty six Mycobacterium avium subsp. hominissuis, one M. chelonae and two M. fortuitum isolates were found in the lymph nodes of pigs. No statistically significant difference was detected between farms A and B for isolation rates of mycobacteria from the lymph nodes of pigs and their species composition. To investigate the source of the pigs' infections, culture examinations of 117 samples from the external environment were performed. Mycobacteria were isolated from 25 samples from the external environment (21.4%). Mycobacterial isolates were also detected in eleven (91.7%) and two (16.7%) of 12 used sawdust and 12 of non-used (fresh) sawdust samples, respectively. None of 12 wood shavings was culture-positive. Twelve of 13 sawdust isolates were classified as M. a. hominissuis of serotypes 6 and 8 and genotype IS901- and IS1245+; the remaining isolate was classified as species M. fortuitum. Other conditionally pathogenic mycobacteria were only isolated from 12 of the remaining 81 samples from the external environment (excluding bedding). A total of eight isolates (two pig and six sawdust samples originating from farms A and B) were examined by IS1245 restriction fragment length polymorphism (IS1245 RFLP) analysis. These isolates produced five distinct IS1245 RFLP types with more than 20 bands. Based on identical IS1245 RFLP types of one pig isolate and two isolates of used sawdust from farm A, we have concluded that contaminated sawdust was the source of mycobacterial infection for pigs in our study.  相似文献   

18.
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   

19.
Streptococcus suis infection in swine. A sixteen month study.   总被引:9,自引:0,他引:9       下载免费PDF全文
A total of 349 isolates of Streptococcus suis retrieved from different tissues from diseased pigs were examined in this study. Only 48% of them could be categorized as one of serotypes 1 to 8 and 1/2. Among typable isolates, serotype 2 was the most prevalent (23%), followed by serotype 3 (10%). The majority of all isolates originated from lungs, meninges/brain, and multiple tissues. Forty-one percent of typable isolates and 33% of untypable isolates were retrieved in pure culture. Other isolates were found in conjunction with Pasteurella multocida, Escherichia coli, Actinobacillus pleuropneumoniae, Actinomyces pyogenes, and other streptococci. Typable S. suis isolates were more frequently isolated from pigs between five and ten weeks of age, while untypable isolates were mostly found in animals aged more than 24 weeks. No obvious monthly and/or seasonal variation of the prevalence of isolation of S. suis could be detected.  相似文献   

20.
Two Corynebacterium strains were isolated from lymph nodes of wild boars showing severe alterations caused by caseous lymphadenitis. The wild boars came from different districts in southern Germany; one was found dead, the other had been shot. The two Corynebacterium strains obtained were both positive for phospholipase D. Further analysis of biochemical profiles did not allow unambiguous differentiation between Corynebacterium ulcerans and Corynebacterium pseudotuberculosis. Fourier-transformed infrared spectroscopy as well as partial sequencing of the genes for 16S rRNA and RNA polymerase beta subunit (rpoB) clearly identified both strains as Corynebacterium ulcerans. The tox gene for diphtheria toxin (DT) could be detected in both porcine isolates by PCR. Partial DNA sequencing of this tox gene showed significant differences from sequences described for other Corynebacterium ulcerans strains and a higher degree of similarity to that of Corynebacterium diphtheria. Production of diphtheria toxin could not be detected. These results indicate that wild game could be a reservoir for zoonotic Corynebacterium ulcerans.  相似文献   

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