Yersinia pseudotuberculosis in the cat.

Yersinia pseudotuberculosis infection in the cat is described. Clinical findings included inappetence, lethargy, rapid emaciation, jaundice and an enlarged left kidney. Chronic pseudotubercular lesions were found in the kidneys and lungs and Yersinia pseudotuberculosis Type IIB was recovered from both sites.     

Experimental infections with wild and mutant Yersinia pseudotuberculosis strains in rabbits

Experimental oral infections of rabbits with a wild-type Yersinia pseudotuberculosis strain (pIB102), and two null-mutants (yopK and ypkA) were carried out with the aim to explore the possibility to use mutant strains of Y. pseudotuberculosis as live carrier vaccine strains. The infectious process of the three strains proceed with passing hyperthermia, leucocytosis with granulocytosis, moderate monocytosis and a transient lymphopenia, better demonstrated at mutant strain infections. Short-term bacterial dissemination into the brain and viscera was observed at yopK infection. An augmented resistance to bactericidal activity of leucocytes at the initial phase of infection was followed by an increased sensitivity discovered earlier in case of yopK strain accompanied by at least 70- and 20-fold, respectively, for ypkA lower virulence for mice. The level of attenuation of yopK was accompanied by significant Yersinia specific IgG and IgM antibody response. Inflammatory foci were found by morphological examination in brain, lung and small intestines after infection with the wild-type strain, while such foci were only observed in brain and mesenterial lymph nodes after infection with the yopK mutant. After infection with the ypkA mutant foci were found in brain and spleen of the infected animals. Morphological changes in the lymphatic tissue of rabbits infected with mutant strains were consistent with induction of immunogenesis. The data suggest that genetically constructed yopK null-mutant exhibits characteristics that makes the strain suitable to be used as a live carrier vaccine to deliver heterologous antigens.     

Yersiniosis in deer from the Otago-Southland region of New Zealand

Samples from 350 routine deer cases submitted to Invermay Animal Health Laboratory for diagnosis during 1979-1982 were examined specifically for the presence of Yersinia sp. An analysis of 57 cases of yersiniosis due to Yersinia pseudotuberculosis is made and two cases due to Yersinia enterocolitica are described. The occurrence of cases appeared strongly correlated with periods of stress, predominantly in winter when cool wet conditions and lack of grazing combined to precipitate the disease. Animals up to one year old were most commonly affected (64% of cases). Of the 61 strains of Yersinia pseudotuberculosis isolated 35 were of Serotype I, 17 of Serotype II and nine of Serotype III. All strains of Yersinia pseudotuberculosis and the strains of Yersinia enterocolitica isolated from the two cases described were Hela cell invasive and gave a positive autoagglutination test for virulence.     

Enterocolitis in cattle associated with Yersinia pseudotuberculosis infection

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.     

Yersinia pseudotuberculosis infection in a suckler calf in the United Kingdom: a case report

Enterocolitis caused by Yersinia pseudotuberculosis was identified by bacterial culture and histopathology in a 5-month old suckler calf. No other significant enteric pathogens were detected. Diagnosis of this condition can be missed if selective media are not used for bacteriology and if histopathology is not attempted or the alimentary tract is unsuitable for examination. This is the first case report of Y. pseudotuberculosis infection in a calf in the United Kingdom.     

Mastitis caused by Yersinia pseudotuberculosis in a cow

Subclinical mastitis with a raised somatic cell count was diagnosed in a cow in her fifth lactation. It was caused by Yersinia pseudotuberculosis, which can also infect humans. This is the first time that Yersinia pseudotuberculosis has been isolated from a mastitis sample in The Netherlands. Despite treatment with antibiotics in the dry period, Yersinia pseudotuberculosis was still present in the same quarter in the subsequent lactation. The somatic cell count was still high and milk production was much lower than in previous lactation. The pathogen did not spread to other quarters of the same cow or to herd mates on the farm over a 1-year period.     

Acetone-treated agglutinin against Yersinia pseudotuberculosis in free-living rats

Retrospective investigation was done on Yersinia pseudotuberculosis infection in barn rat populations living in an Yersinia endemic area and in zoo rat populations living in a nonendemic area. The OH agglutinins against Y pseudotuberculosis were normally distributed within both populations. Most of the OH agglutinin titers and many O agglutinin titers were reduced by treatment of sera with acetone. Sera with O and OH agglutinin titers were assigned to 2 groups, one with a titer less than 1:8 and the other with a titer of greater than or equal to 1:8. Rats harboring the organism did not possess O or OH agglutinin titers greater than 1:8 in acetone-treated sera. In most nontreated sera, OH agglutinin titers were higher than were the O agglutinin titers. However, in most acetone-treated sera, O agglutinin titers were equivalent to OH agglutinin titers. Differences by region and age were observed in acetone-treated O agglutinin titers of greater than or equal to 1:8 against Y pseudotuberculosis. Therefore, it is recommended that to detect antibody against Y pseudotuberculosis in rats, sera should be treated with acetone before the test and O antigen should be used.     

Pseudotuberculosis in marmosets, tamarins, and Goeldi's monkeys (Callithrichidae/Callimiconidae) housed at a European zoo.

Yersinia pseudotuberculosis is an insidious bacterial infectious agent distributed worldwide and endemic to European countries. It has caused several animal deaths and may threaten the effectiveness of breeding projects for endangered species. In this retrospective study, we examine the prevalence of pseudotuberculosis in Jersey Zoo (Channel Islands, U.K.) over a period of 16 yr to obtain information that can be applied to prevent the infection. The efforts made to control the disease through vaccination are also explored. Our results show that pseudotuberculosis has been endemic to Jersey Zoo since 1979 and is responsible for significant animal loss in the Callithrichidae/Callimiconidae group. Mortality due to Y. pseudotuberculosis was seasonal; a high percentage of deaths occurred during wet and cold seasons. No significant difference was found in mortality rates of vaccinated versus nonvaccinated animals. Although the efficacy of vaccination has not been confirmed, we believe that an improved vaccination program could be an important tool in controlling outbreaks of infection in marmosets and tamarins.     

Enteritis in sheep, goats and pigs due to Yersinia pseudotuberculosis infection

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.     

Yersinia species infection of lambs and cull cows at an abattoir

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.     

Enteritis in cattle due to Yersinia pseudotuberculosis infection

A selective medium was used to isolate Yersinia sp from the intestinal tract of 222 scouring cattle in Gippsland during 1985 and 1986. Intestinal infection with Y. pseudotuberculosis, particularly of serotype III, was found to be especially prevalent in weaned calves, yearlings and young adult cattle. Clinically affected cattle had a profuse liquid diarrhoea and many were systemically ill. Haematological changes suggestive of infection were present in 38 of 49 of these cattle. At least 35 cattle died and characteristic microabscesses were demonstrated in the intestinal mucosa of 20 of 26 examined histologically. Y. pseudotuberculosis was sensitive to tetracyclines in vitro and this drug produced a rapid bacteriological cure. Yersiniosis occurred during the winter, spring and early summer. Challenge of adult cattle with Y. pseudotuberculosis serotype III did not result in intestinal colonisation or clinical disease. Intestinal infection was, however, established in 4 weaned calves and haematological changes and antibody production were demonstrated in them. Intestinal microabscesses were seen in three calves killed on days 8, 14 and 18 after challenge. The fourth calf eliminated infection by day 18 and no lesions were demonstrated when it was killed on day 72. There is a very high prevalence of antibodies reacting with Y. pseudotuberculosis serotype III in adult cattle. It is concluded that cattle are a common host for this bacterium, infection being frequent, with clinical and fatal disease occurring occasionally. The factors leading to clinical disease are unknown.     

Yersiniosis in captive exotic mammals.

Within a 2 1/2-month period, Yersinia pseudotuberculosis infection occurred in 3 blesbok (Damaliscus dorcas), 1 dik-dik (Madoqua kirkii), and 1 giant anteater (Myrmecophaga tridactyla) at the National Zoological Park, Washington, DC. Lesions consisted of fibrinonecrotic enteritis and peritonitis, mesenteric lymphadenitis, and embolic pyogranulomatous lesions in the liver, spleen, and lungs. Feed contaminated with the feces of wild rats and pigeons was thought to be the source of infection.     

Ovine abortion and stillbirth due to purulent placentitis caused by Yersinia pseudotuberculosis

Yersinia pseudotuberculosis was isolated from an aborted placenta and stillborn lamb from a sheep flock having multiple abortions. Given intravenously, it caused elevated body temperatures and purulent placentitis in eight of nine ewes. Two ewes died following infection at 2.5 months of gestation. Two ewes infected at 3.5 months gestation aborted; three infected at four months gave birth to weak, premature, or moribund lambs. One ewe infected at 4.5 months gave birth to a healthy lamb. One lamb which died minutes after birth had focal necrotizing hepatitis, a lesion observed in a stillborn lamb during the original disease outbreak. Y. pseudotuberculosis was reisolated from endometrial, placental, and fetal lesions of experimentally infected animals.     

A spontaneous Yersinia pseudotuberculosis-infection in a monkey-colony.

A spontaneous Yersinia pseudotuberculosis (Y.p.) infection in one African Green Monkey (Cercopithecus aethiops), and nine Squirrel Monkeys (Saimiri sciureus), is reported. The clinical findings, laboratory results and pathological findings are presented. The digestive system was the most affected organ in the acute phase of the Y.p. infection, while in the subacute and chronic phases, the alterations of the lymphatic tissues, spleen or liver were severe.     

Recovery of Yersinia pseudotuberculosis from the faeces of healthy cattle

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.     

A cohort study of Yersinia infection in goats

OBJECTIVE: To determine the temporal pattern of Yersinia infections in three goat flocks and examine the influence of management and seasonal factors on the incidence of those infections over a 1-year period. METHODS: A longitudinal study involving monthly culture of faeces for Yersinia spp. from age groups of randomly selected goats on three farms in the Manawatu region of New Zealand. RESULTS: The incidence of excretion of potentially pathogenic Yersinia (Yersinia pseudotuberculosis and Y enterocolitica biotypes 2, 3 and 5) peaked in winter and fell in summer. In contrast, environmental Yersinia (Y enterocolitica biotype 1A, Y frederiksenii, Y intermedia and Y rohdei) showed no clear pattern of seasonal variation. Pathogenic Yersinia were more prevalent in young animals than in adults, while environmental Yersinia were more prevalent in adults. The same type was isolated from the same animal in two or more successive months in about 20 to 25% of cases, and in the remaining cases there was a gap of at least one month between successive isolations, with many animals yielding a particular type on only a single occasion. A notable difference was that with the potentially pathogenic types, no animal had more than one period of time when it was found to be excreting a particular type, suggesting that immunity develops following exposure. In contrast, it was common for environmental types to be isolated from the same animal throughout the study period. Two goats were suspected to have developed clinical yersiniosis but all remaining infected animals showed no clinical signs of infection. CONCLUSIONS: Asymptomatic Yersinia carriage was common in goats in New Zealand, with a clear seasonal and age group pattern of infection with potentially pathogenic types. There was evidence that immunity developed to potentially pathogenic types. This is the first time that Y rohdei has been isolated from goats.     

Faecal survey of deer for Yersinia pseudotuberculosis and Salmonella sp

The results of a national survey of faeces from clinically normal deer for Salmonella sp. and Yersinia pseudotuberculosis are reported. Five isolates of Y. pseudotuberculosis and none of Salmonella sp. were made from 3810 faeces representing 122 farms.     

The differential diagnosis of Salmonella abortus ovis and Yersinia pseudotuberculosis in sheep abortions

55 strains of Salmonella abortus ovis and 3 strains of Yersinia pseudotuberculosis (two serotypes I, one serotype II), isolated out of aborted ovine fetuses from northern Bavaria, were investigated and compared culturally, biochemically and serologically. The identification of S. abortus ovis (group B) could not be achieved by use of Api 20 E. The code-number 4004500/47 identified S. typhi (group D) only. Y. pseudotuberculosis serotype II but not serotype I agglutinated with the polyvalent and the specific anti-0: 4-Salmonella serum. No agglutination was observed with the flagella anti-H-sera.     

Potential wildlife sources of Yersinia pseudotuberculosis for farmed deer (Cervus elaphus)

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.     

Fatal yersiniosis in farmed deer caused by Yersinia pseudotuberculosis serotype O:3 encoding a mannosyltransferase-like protein WbyK.

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.