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1.
Strains of [Actinobacillus] rossii, [Pasteurella] mairii and [Pasteurella] aerogenes can be isolated from abortion in swine. The RTX toxin Pax has previously been found only in those [P.] aerogenes strains isolated from abortion. Nothing is known about RTX toxins in field isolates of the other two species. To gain insight into the distribution of selected RTX toxin genes and their association with abortion, PCR screening for the pax, apxII and apxIII operons on 21 [A.] rossii and seven [P.] mairii isolates was done. Since species can be phenotypically misidentified, the study was backed up by a phylogenetic analysis of all strains based on 16S rRNA, rpoB and infB genes. The pax gene was detected in all [P.] mairii but not in [A.] rossii strains. No apx genes were found in [P.] mairii but different gene combinations for apx were detected in [A.] rossii strains. Most of these strains were positive for apxIII, either alone or in combination with apxII. Whereas pax was found to be associated to strains from abortion no such indication could be found with apx in [A.] rossii strains. Phylogenetically [A.] rossii strains formed a heterogeneous cluster separated from Actinobacillus sensu stricto. [P.] mairii strains clustered with [P.] aerogenes but forming a separate branch. The fact that [P.] aerogenes, [P.] mairii and [A.] rossii can phylogenetically clearly be identified and might contain distinct RTX toxin genes allows their proper diagnosis and will further help to investigate their role as pathogens.  相似文献   

2.
Three strains of the Pasteurella aerogenes complex were isolated as sole pathogens from aborted fetuses of a sow aborted at the 12th week of gestation on a farm of 600 sows. Gross pathology showed no characteristic lesions. The isolates were biochemically identical and resembled P. pneumotropica on the basis of their strong indole and urease positivity but they produced gas, were ornithine decarboxylase negative and fermented mannitol but not trehalose. Only a few differences were apparent in biochemical characteristics between the isolated strains and P. aerogenes. They differed from the type strain of P. aerogenes in ornithine decarboxylase activity, indole production and lactose and mannitol fermentation; however, such strains do occur within this heterogeneous species. At the time of abortion the antibody titre of the aborted sow was 1 in 16 when examined with live bacterial suspension and 1 in 128 if boiled antigen was used. Similar strains could not be isolated from the vaginas of aborted sows or pregnant and newly farrowed sows in the same group. The bacteriological, serological and histological findings support the opinion of other workers on the occasional pathogenic nature of P. aerogenes.  相似文献   

3.
tRNA-intergenic spacer PCR (tDNA-PCR) was evaluated for its effectiveness in differentiating Pasteurella and Mannheimia (sub)species predominantly of ruminant origin. For this purpose, 38 reference strains and 13 field isolates belonging to both genera were investigated. tDNA-PCR enabled discrimination of all Pasteurella species tested (Pasteurella (P.) aerogenes, P. avium, P. canis, P. lymphangitidis, P. multocida, P. trehalosi). For the differentiation of the subspecies of P. multocida, an additional dulcitol reaction was required. Two of the five so far-defined Mannheimia species, M. granulomatis and M. varigena, had a distinct fingerprinting profile. The remaining three phylogenetically highly related species (M. haemolytica, M. glucosida, and M. ruminalis) clustered together. Nevertheless, M. ruminalis is non-haemolytic, and M. haemolytica and M. glucosida can be differentiated on the basis of two additional phenotypic characteristics (beta-glucosidase and aesculin hydrolysis). In conclusion, tDNA-PCR is a useful tool in differentiating organisms belonging to the genera Pasteurella and Mannheimia.  相似文献   

4.
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.  相似文献   

5.
DNA was isolated from 15 strains of Pasteurella anatipestifer and from one strain each of Moraxella nonliquefaciens, M. bovis, Pasteurella multocida, P. haemolytica, P. gallinarum, P. pneumotropica, and P. ureae. The guanine-plus-cytosine contents of P. anatipestifer ranged from 32 to 35 mole %, whereas those of Moraxella and Pasteurella spp. were much higher, ranging from 40 to 45 mole %. DNA-DNA hybridization analysis revealed that homology of nine P. anatipestifer strains to strains ATCC 11845 and PA 15 was 52 to 100%, whereas homology of Moraxella and Pasteurella strains to these strains was only 3 to 17%. Similarly, homology of P. anatipestifer strains, Moraxella, and Pasteurella species other than P. multocida to P. multocida reference strain P-2192 was low. These results strongly suggest that P. anatipestifer is genetically unrelated to either Pasteurella or Moraxella.  相似文献   

6.
Chromosomal DNA from 13 different selected Pasteurella multocida spp. multocida strains of serotypes A and D were isolated and compared. All 10 toxigenic strains were recognized by a DNA probe which included the toxA gene coding for the Pasteurella multocida toxin (PMT). None of the three nontoxigenic strains reacted with the DNA probe. Toxin from the 10 toxigenic strains were isolated and compared. All were found to possess the biological characteristics previously described for the PMT isolated from P. multocida ssp. multocida NCTC 12178, including molecular mass of approx. 143 kDa and reactivity with a series of monoclonal antibodies. Toxin prepared from different toxigenic strains could not be differentiated immunologically by tandem crossed immunoelectrophoresis, Toxin, which was affinity purified from four of the strains and subsequently inactivated by formaldehyde, was cross-protective when used for vaccination of mice before challenge with PMT. It is concluded that the toxin from toxigenic strains of P. multocida ssp. multocida must be very similar, if not identical.  相似文献   

7.
Pasteurella are an important cause of fatal infections in free-ranging bats, but the genetic diversity of bat-derived strains is unclear. In the current study, 81 Pasteurella strains associated with pneumonia, severe organ necroses and systemic infection in free-ranging European vespertilionid bats were characterized by biochemical and molecular typing methods. Genetic relationships and subspecies status of Pasteurella multocida strains were determined by comparative 16S rDNA and rpoB gene sequence analysis. In addition, 30 representatives of the bat-derived P. multocida strains were selected based on phenotypic and genotypic tests to be compared by pulsed-field gel electrophoresis using SmaI. Most (85%) of the Pasteurella strains obtained from free-ranging bats in this study represented P. multocida ssp. septica. P. multocida ssp. multocida and Pasteurella species B were also identified in a small number of isolates. PFGE analysis correlated well with the sequencing results and revealed a high genetic diversity among bat-derived strains of P. multocida ssp. septica. Strains sharing identical or closely related SmaI fragment patterns were cultured from bats of different species, geographic origins, and years of isolation. The presence of numerous different P. multocida strains allows the assumption that Pasteurella infections in vespertilionid bats are not solely based on intra- but also on inter-species transmission. And indeed, our results present evidence of P. multocida infections in bats following cat predation.  相似文献   

8.
The resistance to anti-microbial agents of bacteria isolated from pathological conditions of birds in Victoria, 1978 to 1983, was determined for isolates of Escherichia coli, Salmonella species, Staphylococcus aureus, Pasteurella multocida, P. anatipestifer, Yersinia pseudotuberculosis and Haemophilus paragallinarum. The isolates of E. coli had a high prevalence of resistance to tetracycline and sulphonamides, and a lower prevalence of resistance to furazolidone and sulphamethoxazole-trimethoprim. The isolates of Salmonella spp commonly had resistance to tetracycline, sulphonamides, furazolidone and sulphamethoxazole-trimethoprim. Almost half the isolates of S. aureus showed resistance to lincomysin and many showed resistance to penicillin. Resistance to tetracycline was found in isolates of P. multocida, P. anatepestifer and Y. pseudotuberculosis. Some isolates of H. paragallinarum showed resistance to sulphonamides, streptomycin and sulphamethoxazole-trimethoprim.  相似文献   

9.
Thirty strains of Pasteurella haemolytica which were untypable by the indirect haemagglutination (IHA) test were examined serologically by rapid plate agglutination (RPA), agar gel diffusion (AGD), crossed immunoelectrophoresis (CIE) and counter current immunoelectrophoresis (CCIE) tests. Nine serogroups were identified by CCIE. Serogroup specificity, dependent on two antigens, was present in heated saline extracts of cells. Single representative strains from two serogroups were not pathogenic for specific pathogen-free lambs.  相似文献   

10.
OBJECTIVE: To characterize Pasteurella spp isolated from healthy pack goats and evaluate the effects of administration of a commercial Pasteurella vaccine. ANIMALS: 45 goats. PROCEDURE: Pharyngeal swab specimens and blood samples were collected on day 0 before vaccination with a Pasteurella (Mannheimia) haemolytica serotype A1 bacterin. Samples were also collected from 17 goats on days 21 and 35. Isolated Pasteurella spp were assigned to biovariant groups on the basis of results of biochemical utilization tests and serotyped. Serum antibody titers were determined. RESULTS: Multiple strains of Pasteurella spp were isolated from swab specimens and assigned to 30 nonhemolytic and 14 beta-hemolytic biovariant groups. The most common biovariant isolated was nonhemolytic P trehalosi belonging to group 2. This strain was isolated from 41 goats. Nonhemolytic P haemolytica strains were isolated from 31 goats, whereas beta-hemolytic strains of P trehalosi and P haemolytica were isolated from 8 and 35 goats, respectively. Vaccination with the A1 serotype did not affect the proportion of goats from which we isolated each biovariant group or the number of biovariant groups isolated. CONCLUSIONS AND CLINICAL RELEVANCE: Multiple strains of P haemolytica and P trehalosi belonging to nonhemolytic and beta-hemolytic biovariant groups were isolated from the pharynx of healthy domestic pack goats. Because hemolytic activity correlates with leukotoxin production, beta-hemolytic strains may have a greater potential to cause disease in naive populations of wild ruminants. However, vaccination with an A1 serotype bacterin did not decrease the proportion of culture-positive goats.  相似文献   

11.
Methylated cellular fatty acids of representative strains of Pasteurella spp., Moraxella spp., and P. anatipestifer were subjected to gas chromatography in an attempt to further support the independence of P. anatipestifer from both Pasteurella and Moraxella. All Pasteurella spp. and Moraxella spp. revealed group characteristics specific for each genus that could be easily differentiated from the unique profile of P. anatipestifer. All P. anatipestifer strains tested showed similar fatty-acid profiles in gas chromatography, regardless of host of origin.  相似文献   

12.
Crude dermonecrotic toxins (DNT) were prepared from Pasteurella multocida (P.m.) type D and type A strains isolated from pigs with atrophic rhinitis. Rabbits were immunized with the DNT of P.m. type D. This serum neutralized the DNT of P.m. type A to the same degree as the homologous one both in vitro (cytopathogenicity for tissue culture cells) and in vivo (mouse lethality and dermonecrotic activity in guinea pig).  相似文献   

13.
Six cases of fowl cholera in growing turkeys and 3 in adult breeder chickens of the broiler type as well as one case each of a Pasteurella (P.) multocida-associated disease in ducklings and goslings were described in consideration of own laboratory findings and available informations of the case history. Furthermore a report is given on a treatment strategy successfully used in turkeys with highly acute fowl cholera. All the P. multocida strains isolated culturally could be assigned to the subspecies multocida. In one case Bordetella avium, Salmonella (S.) arizonae and S. hadar were additionally cultured form part of turkeys submitted. P. multocida and Moraxella (Pasteurella) anatipestifer could be determined as the causative agents of the disease of ducklings and goslings. P. multocida strains from turkeys were identified serologically as serovars A:3.4 (3x), F:3.4 (2x) and A:3 (1x); those from the breeder chickens as A:3 (3x); and one each from ducklings and goslings as F:3.4 and -:3. (uncapsulated). No death occurred in turkeys with clinical signs of a highly acute fowl cholera if the treatment of the affected birds was started with an intravenous injection of sulfadimethoxine and continued with a combination of sulfachlorpyridazine (SCP) and trimethoprim (TMP) given in the drinking water for 5 days. However relapse occurred 2-3 days after withdrawal of the drug, although the therapy was clinically highly effective. The recurrence of the disease could be prevented reliably if the turkeys were vaccinated with an effective oil-based bacterin and subsequently treated with the SCP-TMP combination given in drinking water over a 12 day period.  相似文献   

14.
Sheep were immunized three times with a vaccine composed of filtrate from a 36 h culture of Corynebacterium pseudotuberculosis and a block polymer adjuvant. Immunization resulted in the development of exotoxin-neutralizing antibody. This corresponded to the recognition of a 31.6 kDa protein on sequential immunoblots of ammonium sulfate-precipitated filtrate. In addition sera from vaccinated sheep recognized at least eight bacterial cellular antigens on immunoblots of ether-extracted C. pseudotuberculosis, including bands of 12, 25.1, 31.6, 36.3, 39.8, 63.1, 70, 75 or 79.4 kDa. Sera from these sheep altered the colony growth characteristics of C. pseudotuberculosis in vitro. These results indicate that immunization with soluble C. pseudotuberculosis in vitro. These results indicate that immunization with soluble C. pseudotuberculosis antigen preparations that have been used in toxoid vaccines induces antibody responses to numerous cellular antigens in addition to exotoxin and suggest that serologically mediated antibacterial effects could be an important component in the protection from disease that has been reported following immunization with C. pseudotuberculosis toxoids.  相似文献   

15.
The effect of prior natural exposure to Pasteurella haemolytica, as determined serologically, was studied with respect to resistance to experimental pneumonic pasteurellosis in 20 calves from 3 experiments. Resistance to challenge exposure was measured using a lesion-scoring system. As measured by a quantitative fluorometric immunoassay, naturally acquired serum antibody titers to the organisms were 0 to 228. There was a significant correlation (P less than 0.05) between high naturally acquired antibody titers and resistance to transthoracic challenge exposure with P haemolytica.  相似文献   

16.
Outer membrane preparations of various Pasteurella isolates (Pasteurella multocida and some other Pasteurella species) from cattle and swine were extracted by N-lauryl-sarcosine sodium salt. Capsular extracts were prepared by heat treatment. Both preparations bound to epithel cell wall preparations (ECW) of trachea from cattle and to tracheal mucus of cattle and swine. Binding was demonstrated by an enzyme-linked immunosorbent assay (ELISA). Distinct high adherence values were shown by the greater part of membrane preparations of mucoid Pasteurella strains, especially when originating from cattle.  相似文献   

17.
Forty-six strains of Pasteurella anatipestifer isolated from different avian species were examined to determine their serologic types and physiologic characteristics. Serologic types were determined by a gel-diffusion precipitin test. Antigens from 39 field isolates reacted with antisera prepared from seven P. anatipestifer reference strains representing serotypes 1, 2, 4, 6, and 7. Antigens from five isolates did not react and could not be typed with available reagents. Gel precipitin reactions involving serotype 1 (43.6%) and serotype 2 (25.6%) were the most prevalent. Generally, the physiologic characteristics from 40 tests were typical for P. anatipestifer, and variations were observed among the strains in urease production, hemolysin production, litmus milk reaction, and gelatin liquefaction.  相似文献   

18.
Bacterial cell envelope preparations from eight untypable strains ofPasteurella haemolytica were compared by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and immunoblotting with rabbit antisera prepared against the eight untypable strains (one untypable strain per rabbit) and with cattle antisera prepared againstP. haemolytica serotypes 1, 2, 5, 6, 9 and against one heterologous untypable strain. Numerous comigrating and shared antigens were recognized by the eight rabbit antisera and theP. haemolytica serotype cattle antisera. Comigrating antigens at 43 and 30 kilodaltons (kDa) were recognized by all eight rabbit antisera. Shared antigens, detected by all eight rabbit antisera when reacting againstP. haemolytica serotype 1, were recognized at 43, 32, 30, 20 and 15 kDa.  相似文献   

19.
The taxonomic relationship of 131 strains previously identified as Pasteurella multocida obtained from calf pneumonia in West Germany, United Kingdom and Netherlands was investigated by extended phenotypic and limited genotypic characterization. Twenty-four strains were classified as P. multocida ssp. multocida, 15 strains as P. avium biovar 2 and 13 strains as P. canis biovar 2. Sixty-five and five strains were tentatively classified as ornithine negative P. multocida ssp. multocida and P. multocida ssp. septica, respectively. Genetic investigations showed that ornithine negative strains of P. multocida were related on species level. Less genomic binding was found between an ornithine negative strain of P. multocida ssp. septica and the type strains of the three subspecies of P. multocida. The taxonomic position of ornithine negative strains of P. multocida is still under investigation. The taxonomic position of the remaining nine strains is uncertain underlining the need for genotypic characterization within the genus Pasteurella to aid in defining single species by phenotypic tests.  相似文献   

20.
Apx toxins in Pasteurellaceae species from animals   总被引：6，自引：0，他引：6  
Pasteurellaceae species particularly of porcine origin which are closely related to Actinobacillus pleuropneumoniae were analyzed for the presence of analogues to the major A. pleuropneumoniae RTX toxin genes, apxICABD, apxIICA and apxIIICABD and for their expression. Actinobacillus suis contains both apxICABD(var.suis) and apxIICA(var. suis) operons and was shown to produce ApxI and ApxII toxin. Actinobacillus rossii contained the operons apxIICA(var.rossii) and apxIIICABD(var.rossii). However, only the toxin ApxII and not ApxIII could be detected in cultures of A. rossii. The Apx toxins found in A. suis and A. rossi may play a role in virulence of these pathogens. Actinobacillus lignieresii, which was included since it is phylogenetically very closely related to A. pleuropneumoniae, was found to contain a full apxICABD(var.lign.) operon which however lacks the -35 and -10 boxes in the promoter sequences. As expected from these results, no expression of ApxI was detected in A. lignieresii grown under standard culture conditions. Actinobacillus seminis, Actinobacillus equuli, Pasteurella aerogenes, Pasteurella multocida, Haemophilus parasuis, and also Mannheimia (Pasteurella) haemolytica, which is known to secrete leukotoxin, were all shown to be devoid of any of the apx toxin genes and did not produce ApxI, ApxII or ApxIII toxin proteins. However, proteins of slightly lower molecular mass than ApxI, ApxII and ApxIII which showed limited cross-reactions with monospecific, polyclonal anti-ApxI, anti-ApxII and anti-ApxIII were detected on immunoblot analysis of A. equuli, A. seminis and P. aerogenes. The presence of Apx toxins and proteins that imunologically cross react with Apx toxins in porcine Actinobacillus species other than A. pleuropneumoniae can be expected to interfere with serodiagnosis of porcine pleuropneumonia.  相似文献   

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