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1.
Serum samples from Asian elephants (Elephas maximus) in the Kanchanaburi, Chiang Mai and Lampang provinces of Thailand were tested using the microscopic agglutination test against 22 serovars of Leptospira interrogans. A titre of more than 1:100 was used as evidence of infection. In northern Thailand, the seroprevalence was 58 per cent and the prevalent serovars were Leptospira interrogans serovar Sejroe, Leptospira interrogans serovar Tarassovi, Leptospira interrogans serovar Ranarum and Leptospira interrogans serovar Shermani. In western Thailand, the seroprevalence was 57 per cent and the prevalent serovars were L Tarassovi, L Sejroe, L Ranarum, Leptospira interrogans serovar Bataviae and L Shermani. These results were similar to studies in domestic livestock and stray dogs in the Bangkok district. Among the elephants from Kanchanaburi there were significant associations between seropositivity and between the camp and between the prevalent serovars and the camp.  相似文献   

2.
The excretion of Leptospira interrogans serovar hardjo in the urine of cattle was studied in naturally and experimentally infected animals. Five of 15 naturally infected animals with microscopic agglutination test titres of > or = 1:300 shed leptospires for between 28 and 40 weeks. Twenty yearling heifers, experimentally infected by either the supraconjunctival or intrauterine routes, shed leptospires for from eight to 60 weeks; the 10 infected via the uterus shed L interrogans serovar hardjo for a mean of 26 weeks (range eight to 54 weeks) and the 10 infected by the supraconjunctival route shed the organism for a mean of 32 weeks (range 12 to 60 weeks). The results suggest that natural infection results in more prolonged excretion than experimental infection. No intermittent or seasonal excretion of the organism was observed. After the initial experimental infection, large numbers of leptospires were shed in the urine for several weeks, and thereafter there was a progressive decline in the number of organisms shed.  相似文献   

3.
A Leptospira interrogans serogroup australis serovar lora infection in a stud farm is reported. During three successive years (1984-1986) clinical leptospirosis with a severe often rapid, fatal course was seen in 12 foals. Clinical examination revealed severe respiratory distress, depression and pyrexia. Other symptoms were diarrhea (2), jaundice (1), and an unsteady gait (1). Morphological characteristics of the disease were massive pulmonary haemorrhage and haemorrhagic-thrombotic or extracapillary glomerulonephritis with tubulonephrosis and interstitial oedema. In most foals high or increasing MAT titres to serovar bratislava were found; from one foal Leptospira interrogans serovar lora was isolated. Serological examination of all 56 mares at the farm (August 1986) revealed antibodies to serovar bratislava in 64 per cent of the animals. These findings support the idea that Leptospira interrogans serovar bratislava and closely related strains (in this study serovar lora) may be adapted to and maintained by the horse population.  相似文献   

4.
The aim of this study was to determine whether evidence could be obtained of foetal infection with Leptospira interrogans serovar hardjo in aborted foetuses collected from dairy farms. Material from 197 abortions occurring over a wide area of Victoria was collected over 3 years. None of 195 foetal kidney cultures or 7 cultures from membranes was positive for leptospiral organisms. Immunogold silver staining for leptospires was performed on sections of kidneys, lungs or heart from 156 foetuses, with negative results. Evidence of transient leptospiral infection in 11 of 123 foetuses was obtained by foetal heart blood serology. Two isolates of L. interrogans serovar hardjo were obtained from the urine of milking cows. These strains were examined by restriction endonuclease analysis and both were shown to be of the genotype Hardjobovis, as have been all Australian isolates studied so far. It appears that foetal infection with serovar hardjo is not associated with any substantial proportion of bovine abortions in Victoria, in contrast to the situation in Northern Ireland. The apparent absence from Victoria of the pathogenic genotype Hardjoprajitno is a possible explanation.  相似文献   

5.
Objectives – This case series describes 5 dogs with small intestinal intussusception and acute kidney injury due to infection with Leptospira interrogans serovar Australis.
Case Series Summary – Small intestinal intussusception was observed in 4 dogs diagnosed with acute kidney injury due to leptospirosis presented between 1997 and 2005. Intussusception was diagnosed at initial presentation or later during hospitalization. An additional dog fulfilling our inclusion criteria was presented to a small animal specialty clinic nearby and was included. Upon admission, all dogs were severely azotemic and thrombocytopenic. All 5 dogs showed the strongest microscopic agglutination test serology reaction to L. interrogans serovar Australis. Two dogs survived with no apparent residual renal damage, 1 survived with subsequent mild chronic kidney disease, and 2 dogs were euthanized at the owners' request due to a guarded prognosis.
New or Unique Information Provided – Intussusception can occur or may be seen in dogs with leptospirosis due to L. interrogans serovar Australis and patients should be monitored closely for this potential complication. As all 5 dogs described in this case series showed the highest titer for L. interrogans serovar Australis, these precautions may be especially applied in geographic areas where this particular serovar is seen.  相似文献   

6.
During 1981, 265 bovine abortions were investigated by serological and histological methods for evidence of leptospiral infection. Leptospires were demonstrated in the tissues of 10 foetuses by a Levaditi silver impregnation technique. Serological testing of maternal sera indicated that Leptospira interrogans serovar hardjo was associated with 5 of the abortions while the remaining 5 were due to L. interrogans serovar pomona infection. In cases of abortion associated with L. interrogans serovar hardjo leptospires were readily demonstrated in foetal liver, kidney, intestine and heart. They were demonstrated less often in lung and placenta and could not be found in foetal brain. Autolysis did not appear to interfere with the demonstration of leptospires by silver impregnation. No lesions attributable to leptospiral infection were seen in placentas but mild interstitial nephritis was found in some of the foetuses. Fourteen other cows had serological evidence of recent leptospiral infection but leptospires were not detected in foetal tissues. Histological examination of silver impregnated foetal tissues in combination with the microscopic agglutination test was shown to be an effective method for diagnosing abortion associated with L. interrogans serovar hardjo in cattle.  相似文献   

7.
Outer sheath antigen from Leptospira interrogans serovar hardjo type hardjoprajitno and acetic acid extracted antigens from serovar hardjo types hardjoprajitno and hardjobovis were evaluated in an immunoassay for ability to detect hyperimmune rabbit serum to serovar hardjo. The degree of cross-reactivity with hyperimmune rabbit sera to L. interrogans serovars pomona, copenhageni, grippotyphosa, canicola and sejroe, and Leptospira biflexa serovar patoc was also measured for each antigen. All of the antigens reacted with the antiserum to L. interrogans serovar hardjo. The outer sheath antigen however, also showed wide cross-reactivity with the antisera to all of the serovars of L. interrogans tested and with the antiserum to L. biflexa serovar patoc. The acetic acid extracted antigen from either type hardjoprajitno, or type hardjobovis, showed a high degree of specificity for serovar hardjo antiserum. The hardjobovis acetic acid extracted antigen was characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis and immunoblotting, and was incorporated into an indirect ELISA for detection of anti-serovar hardjo antibodies in bovine serum. This ELISA showed a relative specificity of 100% with 156 bovine sera which were negative at a dilution of 1:100 in the microscopic agglutination test (MAT) for L. interrogans serovars hardjo, pomona, sejroe, icterohaemorrhagiae, copenhageni, canicola, and grippotyphosa. The relative sensitivity of this assay with 192 bovine sera which had serovar hardjo MAT titres of > or = 100 was 95.3% (95% confidence limit = 2.99%). The degree of cross-reactivity with 289 bovine sera which had serovar pomona MAT titres of > or = 100 (with no detectable serovar hardjo MAT titres) was approximately 1.0%. This assay was: easily standardized, scored objectively, repeatable, semi-automated and used a non-hazardous antigen that can be routinely prepared in gram amounts.  相似文献   

8.
Specimens from 17 swine herds experiencing reproductive failure were examined for Leptospira interrogans serovar bratislava. Clinical signs observed in these herds included stillborn pigs, weak neonatal pigs, and abortion. Diagnostic tests used to determine L. interrogans serovar bratislava infection were bacteriologic culture, serologic assays to detect antibodies, and immunofluorescence. Examination of fetal serum for antibodies against serovar bratislava and a fluorescent antibody test were the most practical diagnostic procedures.  相似文献   

9.
Slot blot hybridisation studies with total genomic DNA probes were used to compare Leptospira interrogans serovar hardjo strain Hardjoprajitno, strain Hardjobovis and a number of other Leptospira interrogans serovars. Strains Hardjoprajitno and Hardjobovis were found to have little genetic relationship with each other when compared to some of the other serovars tested. Hardjoprajitno is closely related to serovar icterohaemorrhagiae and not to Hardjobovis whereas Hardjobovis is closely related to serovars vietnam, balcanica and javanica but not to serovar icterohaemorrhagiae; this places strain Hardjoprajitno in the species L interrogans and strain Hardjobovis in the species L borgpetersoni. Because of this lack of genetic relatedness between strains Hardjoprajitno and Hardjobovis, it is proposed to remove the prefix Hardjo from the strain name Hardjobovis and call it L borgpetersoni serovar hardjo strain Bovis.  相似文献   

10.
SUMMARY: The enzyme-linked immunosorbent assay (ELISA) was compared with the standard microscopic agglutination test (MAT) as a method for detecting antibodies against Leptospira interrogans serovar hardjo in sheep. Peak antibody levels detected by the 2 tests occurred at different times following experimental infection of sheep. In serums from flocks of sheep with naturally acquired infection there was a 95% correlation between MAT and ELISA with respect to the presence or absence of antibody to serovar hardjo , although the level of correlation of the titres of the 2 tests was low. The 2 tests appeared to measure different antigen-antibody systems. The ELISA would be a useful test for screening large numbers of serums for antibodies to L. interrogans serovar hardjo .  相似文献   

11.
A nested polymerase chain reaction (PCR) using primers from the LipL32 sequence of Leptospira spp. was used to detect shedding of pathogenic leptospires in urine from naturally infected cattle. Amplicons (497bp) were obtained from 21 pathogenic reference serovars belonging to four species (L. interrogans, L. borgpetersenii, L. santarosai, L. kirschneri). DNA was amplified from 26/30 urine samples taken from cattle with suspected leptospirosis and from leptospires cultivated from 10 of these samples. The limit of detection of DNA in the clinical samples was 200pg and the nested PCR detected all pathogenic reference serovars of Leptospira spp. tested. No PCR products were amplified using DNA from other common bacterial species from the bovine urogenital tract or urine, or from the non-pathogenic L. biflexa Andamana serovar. The nested PCR exhibited high specificity and sensitivity for detection of pathogenic serovars in urine from cattle.  相似文献   

12.
A cross-sectional study was carried out in the Basque Country of Spain to determine the seroprevalence of 10 Leptospira serovars in a population of dairy cattle with poor fertility, and a case-control study was carried out in another northern area to investigate the role of Leptospira interrogans serovar Bratislava in abortions. L. Bratislava was the most prevalent serovar in the cross-sectional study, with 25.4 per cent of the cows testing positive in the microagglutination test when a cut-off of 1:10 or higher was applied, followed by Leptospira Hardjo (8.2 per cent), Leptospira Pomona (7.7 per cent), Leptospira Autumnalis (0.7 per cent) and Leptospira Copenhageni (0.1 per cent). In the case-control study the seroprevalence of L. Bratislava was significantly higher among the cows which had aborted when a titre of 1:300 or more was used as a cut-off (9.7 per cent v 3.4 per cent, P=0.008); 69 per cent of the L. Bratislava-infected cows that had aborted apparently aborted as a result of the infection.  相似文献   

13.
In 1996 and 1997, the seroprevalence against Leptospira in parturient sows with premature birth or stillbirth from two herds was investigated. In three out of four sow serum samples obtained in Gunma Prefecture, the antibody titers to Leptospira interrogans serovar copenhageni (M20) were higher than 10,000 (the reciprocal of the serum dilution). Furthermore, the antibody titers to L. interrogans serovar canicola (Hond Utrecht IV) were significantly high in the three sows and the titers ranged from 1,000 to 3,000. In sows obtained in Chiba Prefecture, significantly high antibody titers to serovar copenhageni (M20) were confirmed in eight out of 40 sows, and antibody titers greater than 10,000 in six of them. Significantly high antibody titers to L. interrogans serovar icterohaemorrhagiae (RGA) and L. canicola (Hond Utrecht IV) were confirmed in four and 18 out of the 40 sows, respectively, compared with the titers to the other serovars. These findings may indicate the prevalence of leptospirosis in pig herds in both Gunma and Chiba Prefectures.  相似文献   

14.
Leptospira interrogans serovar hardjo was isolated from urine from dairy cattle in the Onderstepoort area. This was the first successful isolation of this serovar as sole agent causing an abortion storm in the Republic of South Africa. Abortions occurred as early as at 4 months' gestation.  相似文献   

15.
AIM: To conduct a longitudinal serological survey for evidence of Brucella spp and Leptospira spp infection of pre-weaned New Zealand fur seals in a colony on the Otago Peninsula. METHODS: Seal pups were repeatedly captured on a monthly basis from February through to July 2001. Pups were tagged at first capture and a blood sample was taken at each capture event. A total of 163 sera were collected from 118 seal pups. Where sufficient volume was collected, the sera were tested for leptospirosis using the microscopic agglutination test (MAT), and for brucellosis using the competitive enzyme-linked immunosorbent assay (ELISA) for Brucella abortus. RESULTS: None of 128 sera from 101 seals tested positive to the ELISA for B. abortus. All tests for Leptospira interrogans serovars Grippotyphosa, Copenhageni, Bratislava and Leptospira borgpetersenii serovar Ballum were negative at a cut-off of <1/100 dilution. Positive or suspicious titres were found to L. interrogans serovars Canicola and Pomona and L. borgpetersenii serovar Hardjo. The highest titres (12,800) were found to serovar Pomona. The titre to serovar Pomona in one seal rose from <1/50 in March to 12,800 in April and was <1/50 when re-sampled in July. The titre to serovar Pomona in another seal dropped from 12,800 in May to <1/50 in June. These seals also had titres to serovar Hardjo, which rose or fell in the same manner. All suspicious or positive titres occurred in late April and early May, when the pups were approximately 4-5 months old. In June and July, all seals tested were negative. CONCLUSIONS: There was no serological evidence of Brucella infection in the pre-weaned fur seals at the colony. Positive titres to serovars Pomona, Hardjo, or Canicola suggest that a Leptospira species was present at the colony, however isolation or visualisation of the organism is required to confirm this. Care should be exercised when handling New Zealand fur seals to prevent human infection or inadvertent transfer of leptospirosis to another marine mammal species.  相似文献   

16.
Leptospira interrogans serovars grippotyphosa and ballum were isolated from kidney and urine of an American Foxhound pup. The pup was from a litter of 12, all of which were unthrifty. Titers for serovar grippotyphosa in pups from the litter ranged from 200 to 6,400 and 23 of 36 adult dogs in the kennel had titers to that serovar. None of the sera was tested for antibodies to serovar ballum. Leptospires were not isolated from or observed in 2 littermates and 1 penmate, but gram-positive organisms morphologically compatible with Encephalitozoon cuniculi were detected in their brains and kidneys.  相似文献   

17.
Duration of immunity in dogs induced with current commercial inactivated leptospirosis vaccines and evaluated against experimental infection, to date, has hardly been documented. The purpose of the present work was to assess the duration of immunity in dogs that is attainable with a commercial inactivated bivalent leptospirosis vaccine. For this purpose, young dogs were vaccinated twice followed by challenge with either Leptospira interrogans serovar canicola or L. interrogans serovar icterohaemorrhagiae 5 weeks, 27 weeks or 56 weeks after the second vaccination. For assessment of the duration of immunity, titres of agglutinating serum antibodies were measured before and after challenge, and the effects of challenge on a variety of parameters were determined including reisolation of challenge organisms from blood, urine and kidney. Both challenge strains induced a generalised infection in control dogs, the canicola strain being most virulent. From the results with different parameters it appeared that the two vaccinations induced a high rate of protection from generalised infection with canicola and icterohaemorrhagiae at 5, 27 and 56 weeks after the second vaccination. In addition, after 56 weeks, still a high level of immunity against renal infection with sv. canicola and, as a consequence, urinary shedding of sv. canicola bacteria, was demonstrated. It was, therefore, concluded that with this vaccine, using this vaccination schedule, a duration of immunity of 1 year can be attained against infection with both serovars.  相似文献   

18.
Two dogs with clinical histories suggestive of leptospirosis were examined serologically and culturally for evidence of leptospiral infection. Antibodies to Leptospira interrogans serovar bratislava were detected in serum from one dog, and the organism was isolated from urine of that dog. In a serologic survey of dogs in the state of Illinois, reactor rates to bratislava were higher than those to canicola or icterohaemorrhagiae. In cases of suspect canine leptospirosis, serovars such as bratislava, not contained in canine vaccines, should be considered in a differential diagnosis.  相似文献   

19.
Four red deer calves (Cervus elaphus) died with severe nephritis apparently associated with infection by Leptospira interrogans serovar pomona. The sera of 12 in-contact red deer calves were examined for leptospiral agglutinins and nine showed titres to pomona consistent with recent infection. Two also showed titres of 1:100 to serovar hardjo. The urine of five of these in-contact calves was examined periodically over a period of nine months. All were initially leptospiruric, four being infected with pomona and one with hardjo. In four animals leptospiruria could only be detected for up to six months, but one animal infected with pomona was leptospiruric for at least eight months. The apparent source of infection was from infected cattle, and it is suggested that deer are unlikely to act as maintenance hosts for serovar pomona.  相似文献   

20.
Six puppies were infected with a virulent strain of Leptospira interrogans serovar icterohaemorrhagiae and another five animals with a virulent strain of Leptospira interrogans serovar canicola, respectively. Antibodies were examined at 3, 5, 7, 11 and 14 days after infection, using the microcapsule agglutination test (MCAT) and the conventional microscopic agglutination test (MAT). Compared with the MAT, the MCAT detected early specific IgM antibody with high sensitivity. The MCAT titres reached a peak at the 7th day after infection and declined gradually after the 11th day, while the MAT titres increased up to the 14th day.  相似文献   

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