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1.
The features of naturally occurring Yersinia pseudotuberculosis serotype III infections in 16 sheep, one goat and 3 pigs, and Y. pseudotuberculosis serotype I infections in 3 goats, are described. Affected animals usually had diarrhoea and were in poor condition or emaciated. A number were moribund or dead when submitted for necropsy. Thickening of the caecal and colonic mucosa was the only gross lesion attributable to Y. pseudotuberculosis infection, with liver or other visceral abscesses not being seen. Characteristic microabscesses were demonstrated in the intestinal mucosa of 10 sheep, one goat and one pig infected with Y. pseudotuberculosis serotype III and one goat infected with Y. pseudotuberculosis serotype I. Sheep, goats and pigs dosed orally with Y. pseudotuberculosis serotype III, the serotype isolated most commonly from these species, developed intestinal infection. In sheep and pigs, infection was accompanied by diarrhoea. Haematological changes and specific antibodies were elicited in all 3 species in response to infection. Microabscesses were seen in the intestinal mucosa of all experimentally exposed animals. The occurrence of field cases and the results of experimental exposure confirm that Y. pseudotuberculosis serotype III is an enteropathogen of sheep, goats and pigs. The association of Y. pseudotuberculosis serotype I with lesions in a goat, indicates that this bacterium may also be a pathogen of this species. It is concluded that Y. pseudotuberculosis serotype III is an enteric pathogen of a wide range of ungulate species including cattle, buffalo, deer, antelopes, sheep, goats and pigs. Serotypes I and II, while having a more restricted host range, are probably also pathogens of ungulates and, in particular, deer, antelopes and goats.  相似文献   

2.
Enteritis in sheep and goats due to Yersinia enterocolitica infection   总被引:1,自引:0,他引:1  
Yersinia enterocolitica biotype 5, serotype 02,3 was isolated from the intestine of 38 sheep and 8 goats submitted to the laboratory for disease diagnosis. Infected animals were usually young, had diarrhoea and were in poor condition or emaciated. A number were moribund or dead when submitted. Characteristic microabscesses were demonstrated in the intestine of 5 of 38 sheep and 3 of 8 goats and no alternative cause of morbidity or mortality was established in these animals. Of the 33 sheep and 5 goats infected with Y. enterocolitica in which microabscesses were not demonstrated, a number of other diagnoses were made, including internal parasitism (18), selenium deficiency or white muscle disease (6) and cobalt deficiency (2), so that morbidity and mortality were possibly unrelated to Y. enterocolitica infection. Five of 6 sheep exposed experimentally by mouth to Y. enterocolitica biotype 5, serotype 02,3 developed an intestinal infection. Although infected sheep showed no clinical evidence of disease and haematological and biochemical indices remained normal, multiple intestinal microabscesses typical of yersiniosis were demonstrated in 3 of 5 infected sheep. It is concluded that Y. enterocolitica biotype 5, serotype 02,3 is an enteropathogen of sheep and goats. Since sheep and goats may be the specific hosts of this bacterium, its virulence for these species is apparently low. Morbidity and mortality may, therefore, be unusual manifestations of infection.  相似文献   

3.
A syndrome in cattle of diarrhoea and death associated with enteric Yersinia pseudotuberculosis infection is described. Outbreaks occurred during winter and early spring in adult cattle grazing pastures waterlogged by recent flooding or persistent heavy rain. Antibiotic therapy was effective early in the course of the syndrome. At necropsy there was severe acute enterocolitis, and bacteria consistent with Y. pseudotuberculosis were observed in the lesions. This organism could usually be isolated from the intestines of affected animals but was recovered less often from other organs. Representative isolates were identified as Y. pseudotuberculosis serotype III. The association of this syndrome with waterlogged pastures and low temperatures suggests that these conditions favour transmission of Y. pseudotuberculosis infection in cattle. The role of Y. pseudotuberculosis as primary pathogen requires confirmation.  相似文献   

4.
Yersiniosis was prevalent among a caprine herd during the late autumn of 2003 in Iwate Prefecture, Japan. The disease affected 29 of about 100 lactating goats, but not dried or nonparous goats, mature male goats or kids. Four animals died within an epidemic period of 20 days. Affected animals developed decreased milk production with subsequent watery diarrhea, neutrophilia with increased band forms and multiple microabscesses characteristic of yersiniosis in the intestinal mucosa from the jejunum to caecum as well as in the mesenteric lymph nodes. Y. pseudotuberculosis serotype III was isolated from intestinal contents and mesenteric lymph nodes. The organism was also cultured from clinically normal dried animals. The outbreak might have been precipitated by multiple stress factors, such as lactation, cold weather, Corynebacterium pseudotuberculosis infection resulting in abscess formation and tapeworm and coccidium parasitisms.  相似文献   

5.
Attempts were made to recover and serologically identify Yersinia pseudotuberculosis from the faeces of groups of nine to twenty clinically healthy cattle eight to thirteen months old on each of 50 farms in the northern part of New Zealand. Yersinia pseudotuberculosis was recovered from 134 (26.3%) of 509 faeces samples from cattle on 42 (84%) farms and from nine of ten samples on two of these farms. Serotypes I, II, and III were identified, of which serotype III was by far the most common and accounted for 125 (93.2%) of the 134 isolates. Because of the common occurrence and widespread distribution of Y. pseudotuberculosis it is suggested that the clinical significance of isolation of this micro-organism from faeces samples or intestinal contents should be treated with caution.  相似文献   

6.
It is reported on four cases of pseudotuberculosis in 2 Saimiri sciureus, 1 Callithrix jacchus/penicillata hybrid and 1 S. oedipus. The animals came from two different groups, one being infected with Y. pseudotuberculosis serotype I, the other with Y. pseudotuberculosis serotype II. All cases showed intestinal infection of thermophile Campylobacter. Remarkable were severe haemorrhagic components and the distinct RHS-proliferation, especially in the mesenteric lymphatic nodes.  相似文献   

7.
The rectal contents of 330 cull cows and 66 lambs were sampled over the 1984-1985 killing season at a New Zealand freezing works for the presence of Yersinia species. Samples from the cows revealed one isolation of Y. pseudotuberculosis and one isolation of Y. intermedia. Samples from the lambs gave thirteen isolates of Y. enterocolitica, three of Y. inter-media, two of Y. pseudotuberculosis and one of Y. frederiksenii. Two of the isolates of Y. enterocolitica were shown to be serotype 0:3. Although no parallel studies were carried out on young cattle or adult sheep, these findings are consistent with the hypothesis that Yersinia infection primarily involves young animals. Thus there exists the potential for transmission of the above species of Yersinia from young animals to man which needs further detailed study.  相似文献   

8.
In 40 submissions to the Regional Veterinary Laboratory (RVL) Wagga Wagga from sheep in southern New South Wales from 1981 to 1989, 53 isolates of Yersinia sp were recovered from 45 sheep in 37 flocks. Of 53 isolates, 26 were identified as Y. pseudotuberculosis, 20 as Y. enterocolitica, 5 as Y. intermedia and 2 as Y. frederiksenii. Twelve isolates of Y. pseudotuberculosis tested in the slide agglutination test all belonged to serotype III. The 20 Y. enterocolitica isolates were categorised biochemically as biotype 5 strains and, of 6 isolates serotyped, all belonged to serogroup 2,3. Outbreaks of yersiniosis were most common in late winter and early spring and affected flocks often had experienced a change in husbandry. Infection with Yersinia sp was associated with diarrhoea, illthrift and mortality. At necropsy, congestion and occasionally thickening of the intestinal mucosa were observed in affected sheep. Gastrointestinal nematodiasis and coccidiosis often were concurrent findings. The characteristic histological lesion in sheep infected with Y. pseudotuberculosis was acute segmental suppurative erosive enterocolitis. There were no lesions consistently associated with Y. enterocolitica, Y. intermedia or Y. frederiksenii.  相似文献   

9.
Abstract The development of disease following oral challenge with Yersinia pseudotuberculosis (serotype 11) was compared in four groups of five birds treated with a parenteral dose of 10 mg iron dextran (Imferon), 10 mg of iron dextran plus 10 mg of the chelating agent desferrioxamine (Desferal), 10 mg of desferrioxamine or 10 mg of dextran 2 days before the experiment. Four groups of two birds received the above treatment regimens but no bacterial challenge. In iron dextran treated birds, oral challenge resulted in faecal shedding for the 10 day duration of the experiment, whereas in those birds which received dextran or desferrioxamine alone, the duration of faecal shedding was significantly less. Serological titres to the lipopolysaccharide antigen of the challenge bacteria were also lower in the groups not pretreated with iron dextran. The birds pretreated with iron dextran had diarrhoea and were clinically unwell 2 days following the initial oral challenge. Birds not given iron dextran showed no clinical signs of disease. Histological examination of five selected areas in the liver, spleen and intestine of each bird indicated that birds in the groups treated with iron dextran prior to bacterial challenge had significantly more intestinal lesions than birds in the groups not treated with iron. In contrast, there were significantly more lesions in the spleens of birds not pretreated with iron dextran. There was no evidence of stainable iron in the livers of birds challenged with Y pseudotuberculosis 10 days after an injection of 10 mg of iron dextran. This is in contrast to birds given iron dextran and no bacteria. It was concluded that pretreatment of birds with iron dextran resulted in more severe clinical disease, prolonged faecal shedding with associated intestinal lesions and higher serological titres to bacterial antigen. The number of lesions in the spleen and liver was not necessarily correlated with the severity of clinical disease, and in all infected birds the hepatic iron levels were significantly lower than in the non-infected control birds 10 days after oral challenge. It seems probable that the chicken has a high requirement for iron during infection with Y pseudotuberculosis and mobilises stored and exogenously supplied iron for tissue repair and immunological function.  相似文献   

10.
Two gnotobiotic calves were treated once with tilmicosin (20 mg kg-1) six hours before they were infected by the intratracheal route with Mycoplasma bovis and Pasteurella haemolytica serotype 1. This treatment prevented colonisation of the lungs by P haemolytica and considerably reduced colonisation by M bovis, and the clinical scores and the extent of pneumonic consolidation, compared with two untreated gnotobiotic calves, both of which had to be killed in extremis for humanitarian reasons within 24 hours of infection. In a second experiment, 10 conventionally reared calves were similarly exposed to infection and, at the onset of clinical disease, five were treated once with tilmicosin (20 mg kg-1). Colonisation by P haemolytica and M bovis, the clinical scores and extent of pneumonic consolidation were suppressed or greatly reduced in the treated compared with the untreated calves, one of which had to be killed in extremis two days after infection. It was concluded that tilmicosin had a beneficial effect.  相似文献   

11.
The safety, efficacy and cross-protectivity of a live intranasal aerosol haemorrhagic septicaemia vaccine containing Pasteurella multocida serotype B:3,4 were tested in young cattle and buffaloes in Myanmar, where more than 1.5 million animals had been inoculated with this vaccine between 1989 and 1999. A recommended dose of 2 x 10(7) viable organisms was used for the efficacy test. The administration of 100 times the recommended dose to 50 cattle and 39 buffalo calves was innocuous. Seven months after they were vaccinated, three of three buffaloes were protected and 12 months after they were vaccinated, three of four buffaloes were protected against a subcutaneous challenge with serotype B:2 which killed three of three unvaccinated buffaloes. Twelve months after they were vaccinated, eight of eight cattle survived a serotype B:2 challenge, which killed four of four unvaccinated controls. The vaccinated cattle had developed serum antibodies detectable by the passive mouse protection test. Indirect haemagglutination tests on sera taken from cattle 10 days and five weeks after they were vaccinated showed high titres of antibodies. The serum of vaccinated cattle cross-protected passively immunised mice against infection with P. multocida serotypes E:2, F:3,4 and A:3,4.  相似文献   

12.
Potential vertical transmission of wild-type bluetongue virus serotype 8 (BTV-8) in cattle was explored in this experiment. We demonstrated transplacental transmission of wild-type BTV-8 in one calf and oral infection with BTV-8 in another calf. Following the experimental BTV-8 infection of seven out of fifteen multi-parous cows eight months in gestation, each newborn calf was tested prior to colostrum intake for transplacental transmission of BTV by RRT-PCR. If transplacental transmission was not established the calves were fed colostrum from infected dams or colostrum from non-infected dams spiked with BTV-8 containing blood. One calf from an infected dam was born RRT-PCR positive and BTV-specific antibody (Abs) negative, BTV was isolated from its blood. It was born with clinical signs resembling bluetongue and lived for two days. Its post-mortem tissue suspensions were RRT-PCR positive. Of the seven calves fed colostrum from infected dams, none became infected. Of the six calves fed colostrum from non-infected dams spiked with infected blood, one calf became PCR-positive at day 8 post-partum (dpp), seroconverted 27 days later, and remained RRT-PCR and Abs positive for the duration of the experiment (i.e., 70 dpp). This work demonstrates that transplacental transmission in late gestation and oral infection of the neonate with wild-type BTV-8 is possible in cattle under experimental conditions.  相似文献   

13.
Sudden death of 9 deer occurred in a large enclosed deer farm with approximately 400 heads of cervids. Fatal yersiniosis was diagnosed in 2 deer that were submitted for laboratory diagnosis. Histopathologically, the disease was characterized by multifocal pulmonary hemorrhage and mild interstitial pneumonia, marked diffuse cholangiohepatitis, minimal myocarditis with mild myocardial degeneration, and mild multifocal suppurative cystic colitis. Yersinia pseudotuberculosis was isolated from the lungs and colon of the affected animals. The isolates were PCR-positive for genes virF, inv, yopB, and yopH, which are essential for invasion and colonization of host intestine and lung. The isolates reacted with polyclonal antibodies against serotype O:3 antigen. The O-genotyping patterns of the isolates were identical with each other, but different from those of the 21 O-genotypes (or serotypes) reported previously. In addition to the O-antigen genes possessed by classical serotype O:3, a gene (wbyK) encoding a mannosyltransferase-like protein was detected in these isolates. The wbyK gene of the isolates showed 94% of DNA sequence homology with the wbyK gene harbored by Y. pseudotuberculosis O:1b. On the basis of pathology, bacteriology, and serology, the authors concluded that the acute deaths of these deer were caused by Y. pseudotuberculosis infection. Molecular characterization of the isolate revealed a genetic heterogeneity in the O-antigen gene cluster of Y. pseudotuberculosis serotype O:3.  相似文献   

14.
Experimental production of bovine pneumonic pasteurellosis   总被引:1,自引:0,他引:1  
Pneumonic pasteurellosis has been reproduced in conventional, weaned, Friesian-cross calves using a strain of Pasteurella haemolytica biotype A, serotype 1 (P haemolytica A1) isolated from a pathologically confirmed incident of bovine pneumonic pasteurellosis. The major clinical findings were pyrexia, hyperpnoea, tachypnoea, nasal discharge and reduced appetite. Fibrinous pneumonia was present in the lungs of animals at necropsy on days 2 and 3 after initial infection while by days 9 and 10 after initial infection many of the areas of fibrinous pneumonia were confined by a fibrous capsule forming well defined nodules. During the experiment natural transmission of the infecting strain of P haemolytica A1 occurred in two control calves which developed a condition identical to that in the artificially infected calves. P haemolytica A1 was repeatedly recovered from the nasopharynx of infected calves and at necropsy throughout the upper and lower respiratory tracts. Seroconversion, as measured by indirect haemagglutination, to the organism developed in all infected calves by days 9 and 10 after initial infection. The clinical, microbiological and pathological findings were identical to those seen in field incidents of bovine pneumonic pasteurellosis involving recently housed, weaned, single-suckled calves.  相似文献   

15.
As a result of a BVDV infection in a herd consisting of 95 adult cattle 17 cows aborted their calves within a period of 3.5 months, one third got severe diarrhoea, 3 cows died and an increased percentage of the cattle got lochiometra after calving or abortion. The disease was diagnosed by paired serological testing of cattle with diarrhoea or abortion and post mortem examination of several aborted calves. From one foetus BVDV virus was isolated and subsequently subtyped by sequencing. Of aborting cattle, the testing results were influenced by the interval between infection and abortion. These results indicate that a primary infection with BVDV subtype 1b can cause severe clinical symptoms in a dairy herd.  相似文献   

16.
The performance of 2 competitive enzyme-linked immunosorbent assays (C-ELISA) was compared with the reference C-ELISA I for the detection of antibodies to bluetongue virus (BTV). One of the assays (C-ELISA II) used a group-specific monoclonal antibody (MAb) to BTV, obtained from the American Type Culture Collection (8A3B-6) and tissue culture (TC)-derived BTV antigen (Ag), and the other assay (C-ELISA III) used BTV core protein VP7 (expressed in yeast) and the reference MAb (Pirbright Laboratory, 3-17-A3). Test sera were obtained by sequential blood samples from 22 calves, each inoculated with a different serotype (T) of BTV (South African [SA] T-1-T-16 and T-18-T-20 and USA T-11, T-13, and T-17). Sera were also obtained from 4 calves and 4 sheep inoculated with USA BTV T-10 and from several groups of calves exposed to single or multiple doses of epizootic hemorrhagic disease virus (EHDV) T-1-T-4 grown in TC (BHK-21) or suckling mouse brain (SMB). A total of 618 bovine and ovine field sera collected from BT-free and BT-endemic areas were also tested. The C-ELISA III was more sensitive than the C-ELISA II in the detection of anti-BTV antibody in sera from cattle and sheep early after infection with BTV. Seroconversion was demonstrated by the 3 C-ELISAs in all animals inoculated with BTV by 20 days postinfection (DPI), except in calves that received SA T-3 or USA T-13, which became positive at 40 DPI.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

17.
CASE DESCRIPTION: Severe disease and death in cows and calves affected 1 of 3 separate groups (A, B, and C) of cattle on a commercial cow-calf operation. CLINICAL FINDINGS: Clinical illness consisting of severe watery and bloody diarrhea, dehydration, weakness, and death affected adult cows and calves in 1 group (group B). Salmonella enterica serotype Newport was recovered from tissues of cows and calves from group B. TREATMENT AND OUTCOME: Despite supportive and antimicrobial treatment of cattle in group B, cow mortality rate attributable to salmonellosis in that group was 7.9% (32/407); calf mortality rate was 14.4% (52/361). None of the cows in Groups A or C died, and the calf mortality rate in those groups was low. Salmonella enterica serotype Newport was recovered from pooled fecal samples subsequently collected from each group of cows. Bovine viral diarrhea virus (BVDV) antigen was identified in an ear notch sample collected from a necropsied calf from group B. Subsequently, ear notch specimens from cattle in all 3 groups were tested for BVDV antigen. A significantly higher proportion of calves persistently infected with BVDV was identified in group B (8/295 [2.7%]), compared with the proportion in groups A and C combined (1/287 [0.3%]). CLINICAL RELEVANCE: Outbreaks of disease attributable to Salmonella Newport infection in beef cattle are unusual. Because of the immunosuppressive nature of BVDV, the possibility of animals persistently infected with BVDV within the herd should be considered during investigation of unusual outbreaks of infectious diseases.  相似文献   

18.
During 1982 and 1983 15 serotype I, 6 serotype II, 1 serotype III and 3 untyped strains of Yersinia pseudotuberculosis were isolated from 675 apparently normal small mammals and birds from the Invermay farm and nearby rubbish tip with the following prevalence rates: feral cats 27.8%, Norway rats 8.6%, mice 5.5%, hares 3.8% rabbits 1.9% ducks 5.3%, sparrows 2.3%, seagulls 2.3% and starlings 1.7%. For rabbits a significantly higher prevalence of infection was found in the autumn/winter period (4.8%) than the spring/summer period (0%). Insufficient numbers of other mammals were obtained to demonstrate any seasonal difference in prevalence. All bird isolations were obtained between March and July (8/158) compared with none from August to October (0/144). It appears that a number of free-living species of small mammal and birds may be reservoir hosts for Y. pseudotuberculosis and potential sources of infection for red deer on the Invermay farm.  相似文献   

19.
Listeria monocytogenes is a Gram-positive facultative intracellular bacteria which infects a wide range of hosts. In ruminants, infection with L. monocytogenes frequently causes encephalitis, which is usually fatal in sheep and goat, while cattle often recover with antibiotic therapy. Since the role of NO in the control of Listeria is controversial, we have studied the expression of iNOS in the brains of cattle, sheep and goats which had succumbed to listeria encephalitis. iNOS was demonstrated in decreasing intensity in the M phi of microabscesses from cattle, sheep and goat. iNOS expression was accompanied by NT in the microabscesses of cattle, but was only present to a low degree in sheep and was absent in goats. This is indirect evidence for differences in the ability to produce NO in the three species. Presence of iNOS and NT were inversely correlated with the numbers of bacteria. While microabscesses of goats contained high amounts of L. monocytogenes they occurred only rarely in cattle. To corroborate our hypothesis that NO is involved in the control of listeria encephalitis a new animal model was developed. Eleven day old infant rats were infected intracisternally with a low dose of L. monocytogenes. This resulted in a transient meningoencephalitis with moderate clinical signs and low mortality. Listeria proliferated strongly in the inflammatory lesions during the first days of infection, reached a peak at day 4 and were eliminated until day 7. The presence of bacteria was closely accompanied by high numbers of iNOS-expressing M phi and the formation of NT. Administration of the iNOS inhibitor L-NIL or the radical scavenger PBN resulted in rapid death of the treated animals. However, the increase in bacterial numbers was one order of magnitude higher for animals treated with PBN compared with L-NIL administration. This shows that NO plays an important role in the control of a brain infection with Listeria, but suggests that reactive oxidants other than NO are also involved. In conclusion, our findings point to a possible involvement of the differences in the ability to express iNOS and subsequent NO production in the different clinical outcome of listeria encephalitis in cattle and small ruminants.  相似文献   

20.
Bovine respiratory syncytial virus (BRSV) is an important cause of respiratory disease among calves in the Danish cattle industry. An experimental BRSV infection model was used to study the pathogenesis of the disease in calves. Broncho alveolar lung lavage (BAL) was performed on 28 Jersey calves, of which 23 were experimentally infected with BRSV and five were given a mock inoculum. The presence of the cytokine tumor necrosis factor alpha (TNF-alpha) in the BAL fluids was detected and quantified by a capture ELISA. TNF-alpha was detected in 21 of the infected animals. The amount of TNF-alpha in the BAL fluid of calves killed post inoculation day (PID) 2 and 4 was at the same very low level as in the uninfected control animals. Large amounts of TNF-alpha were detected on PID 6, maximum levels of TNF-alpha were reached on PID 7, and smaller amounts of TNF-alpha were seen on PID 8. The high levels of TNF-alpha appeared on the days where severe lung lesions and clinical signs were obvious and the amounts of BRSV-antigen were at their greatest. Although Pasteurellaceae were isolated from some of the BRSV-infected calves, calves treated with antibiotics before and through the whole period of the infection, as well as BRSV-infected calves free of bacteria reached the same level of TNF-alpha as animals from which bacteria were isolated from the lungs. It is concluded that significant quantities of TNF-alpha are produced in the lungs of the calves on PID 6-7 of BRSV infection. The involvement of TNF-alpha in the pathogenesis of, as well as the anti-viral immune response against, BRSV infection is discussed.  相似文献   

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