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Pasteurella species B has so far only been reported from the oral cavity of dogs, cats and a ferret. In the present study, information from 15 recent isolates from different sources, including African hedgehogs (Atelerix albiventris), banded mongoose (Mungos mungo), Moholi bushbabies (Galago moholi) and pneumonia of a cat, were compared to five strains investigated previously from bite wounds in humans inflicted by a cat and dog and from gingiva of a cat. rpoB gene sequence comparison showed that 17 isolates, including the reference strain (CCUG 19794(T)), had identical sequences, whereas two were closely related and demonstrated 97.9 and 99.6 % similarity to strain CCUG 19794(T), respectively; the type strain of Pasteurella stomatis was the most closely related strain, with 92.3 % similarity. This is within the mean range (76-100 %) of rpoB gene sequence similarity between species of the same genus within the family Pasteurellaceae. 16S rRNA gene sequencing of four strains selected based on rpoB sequence comparison showed at least 99.7 % similarity between strains of Pasteurella species B, with 96.2 % similarity to the type strain of the closest related species (Pasteurella canis), indicating that Pasteurella species B should have separate species status. Separate species status was also documented when recN sequence comparisons were converted to a genome similarity of 93.7 % within Pasteurella species B and 59.0 % to the type strain of the closest related species (P. canis). Based on analysis of the phylogenetic and phenotypic data, and since most isolates originate from the oral cavities of a diverse group of animals, it is suggested that these bacteria be classified as Pasteurella oralis sp. nov.; the type strain is P683(T) ( = CCUG 19794(T) = CCM 7950(T) = strain 23193(T) = MCCM 00102(T)), obtained from a cat. Previous reports of the type strain have shown ubiquinone-8, demethylmenaquinone-8 and menaquinone-8 as the major quinones. Polyamines in the type strain were reported as diaminopropane, putrescine, cadaverine, sym-norspermidine, spermidine and spermine in a previous investigation, and the major fatty acids of the type strain were reported to be C(16:0), C(16:1)ω7c and C(14:0), with minor amounts of C(18:0) and C(18:1)ω9c. The DNA G+C content of the type strain has been reported to be 40.0 mol%.

A collection of 12 strains, isolated from diseased tortoises and tentatively identified as [Pasteurella] testudinis-like based on phenotypic characters, was compared with three reference strains of [P.] testudinis. All strains could be separated from the reference strains with respect to 16S rRNA gene sequences, partial sequences of the rpoB housekeeping gene and by phenotypic characters. Based upon differences in 16S rRNA and rpoB gene sequences, the new isolates are suggested to represent a novel species in a new genus of the family Pasteurellaceae Pohl 1981, for which the name Chelonobacter oris gen. nov., sp. nov. is proposed. The type strain is 1662(T) (=CCUG 55632(T)=DSM 21392(T)). beta-Haemolysis and acid production from (+)-l-arabinose, dulcitol, (-)-d-mannitol, (+)-d-mannose, trehalose and salicin separated the new strains from members of existing genera of the family Pasteurellaceae, in addition to the beta-galactosidase, urease and alpha-glucosidase reactions. Differences in indole production, phosphatase, beta-glucosidase and production of acid from dulcitol and trehalose separated C. oris from [P.] testudinis. Several phenotypic characters separated C. oris from Bisgaard's taxa 14 and 32.

[Pasteurella] trehalosi is an important pathogen of sheep, being primarily associated with serious systemic infections in lambs but also having an association with pneumonia. The aim of the present investigation was to characterize a broad collection of strains tentatively identified as [P.] trehalosi in order to reclassify and rename this taxon to support improvements in our understanding of the pathogenesis and epidemiology of this important organism. The type strain for [P.] trehalosi, strain NCTC 10370(T), was included along with 42 field isolates from sheep (21), cattle (14), goats (1), roe deer (3) and unknown sources (3). An extended phenotypic characterization was performed on all 43 strains. Amplified fragment length polymorphism (AFLP) was also performed on the isolates. Two of the field isolates were subjected to 16S rRNA gene sequencing. These sequences, along with five existing sequences for [P.] trehalosi strains and 12 sequences for other taxa in the family Pasteurellaceae, were subjected to a phylogenetic analysis. All the isolates and the reference strains were identified as [P.] trehalosi. A total of 17 out of 22 ovine isolates produced acid from all glycosides, while only four out of 14 bovine isolates produced acid from all glycosides. All 22 ovine isolates were haemolytic and CAMP-positive, while no other isolate was haemolytic and only two bovine isolates were CAMP-positive. Nineteen AFLP types were found within the [P.] trehalosi isolates. All [P.] trehalosi isolates shared at least 70 % similarity in AFLP patterns. The largest AFLP type included the type strain and 7 ovine field isolates. Phylogenetic analysis indicated that the seven strains studied (two field isolates and the five serovar reference strains) are closely related, with 98.6 % or higher 16S rRNA gene sequence similarity. As both genotypic and phenotypic testing support the separate and distinct nature of these organisms, we propose the transfer of [P.] trehalosi to a new genus, Bibersteinia, as Bibersteinia trehalosi comb. nov. The type strain is NCTC 10370(T) (=ATCC 29703(T)). Bibersteinia trehalosi can be distinguished from the existing genera of the family by the observation of only nine characteristics; catalase, porphyrin, urease, indole, phosphatase, acid from dulcitol, (+)-d-galactose, (+)-d-mannose and (+)-d-trehalose.

Aim: To investigate if taxon 42 of Bisgaard isolated from pigs represents genuine [Pasteurella] caballi, which was previously only isolated from horses., Methods and Results: A total of 15 field isolates from horses and pigs from five different countries representing three continents were subjected to extended phenotypical characterization. Although minor differences were observed between taxon 42 and [P.] caballi, these differences did not allow phenotypic separation. Ribotyping based on HindIII digestion showed five profiles based on nine band positions. One [P.] caballi strain and two taxon 42 strains shared the same profile. Ribotyping using HpaII gave a higher diversity with nine profiles based on ten band positions. While no profiles were shared between the taxon 42 and [P.] caballi strains, pattern analysis showed that two of the taxon 42 isolates were most similar (91% similarity) with a [P.] caballi isolate. The 16S rRNA gene sequencing of one strain of taxon 42 and one strain of [P.] caballi was performed and compared with the published sequence for the type strain of [P.] caballi. The three strains showed nearly identical sequences with at least 99.8% similarity. DNA re-associations measured by the micro-well method were 79 and 77%, respectively between the type strain of [P.] caballi and two strains of taxon 42 representing distinct ribotypes and confirmed that taxon 42 belongs to [P.] caballi., Conclusion: The present investigation documents that [P.] caballi can be isolated from clinical respiratory specimens from pigs and the recognized association with respiratory infections in horses and horse bite infection in humans. Strains classified as taxon 42 are [P.] caballi isolated from pigs and for both pigs and horses, lesions mainly include the respiratory tract., Significance and Impact of the Study: The results will improve the diagnostics and progress studies of virulence and epidemiology of [P.] caballi.

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.

Pasteurella gallinarum has been considered an opportunistic pathogen rather than a primary pathogen for chickens. As P. gallinarum has been found to have a high genotypic diversity, one would expect a polyclonal distribution among isolates from different farms if this organism is a secondary invader. The aims of this investigation were to genetically characterize isolates obtained from outbreaks affecting several turkey farms to confirm the existence of the infection in turkeys and to investigate the genetic relationship between isolates from affected farms. A total of 17 isolates from 14 outbreaks of respiratory disease in Germany were subjected to extended phenotypic and genotypic characterization. All isolates were of the same phenotype, typical of P. gallinarum. Ribotyping of three isolates using either HpaII or HindIII showed that they had identical profiles and indicated that the isolates all originated from the same clone. Comparison with HpaII ribotypes from a previous study showed that the pattern was identical to that obtained with isolates from a Zimbabwean outbreak in chickens during 1999 to 2000. Restriction endonuclease analysis typing of 14 isolates from all 14 farms showed that they had identical profiles but these differed from those obtained with isolates from the Zimbabwean outbreak. Sequencing of the 16S rRNA gene and sequence comparisons with other Pasteurellaceae confirmed their classification as P. gallinarum. Identification of the same clone of P. gallinarum from 14 outbreaks of acute respiratory disease in turkeys within a time period of 2 months suggests a common source of infection, and that P. gallinarum probably played a primary role rather than a secondary role in the outbreaks.

The aim of this study was to improve the definition and identification of a group of veterinarily important bacteria referred to as the [Pasteurella] aerogenes-[Pasteurella] mairii-[Actinobacillus] rossii complex. These organisms have mainly been isolated from the reproductive and intestinal tracts of pigs and in most cases have been considered as opportunistic pathogens. A collection of 87 strains were characterized by phenotypic analysis from which 41 strains were selected for 16S rRNA gene sequence comparison, out of which 23 have been sequenced in the present study. One group of 21 strains phenotyped as biovars 1, 3-5, 9-11, 19 and 25-27, including the type strain of [P.] aerogenes, showed 16S rRNA gene sequence similarities of 99.6 % or higher; another group of 18 strains including biovars 2, 6-8, 12-15, 21, 23, 24 and 26A and the type strain of [A.] rossii showed 97.8 % or higher 16S rRNA gene sequence similarity. Between the two groups, 93.8-95.7 % 16S rRNA gene sequence similarity was observed. Strains of [P.] mairii showed 99.5 % similarity, with 95.5-97.2 and 93.8-95.5 % similarity to strains of [P.] aerogenes and [A.] rossii, respectively. Four strains could not be classified with any of these groups and belonged to other members of Pasteurellaceae. Comparisons were also made to DNA-DNA hybridization data. Biovars 1, 9, 10, 11 and 19, including the type strain of [P.] aerogenes, linked at 70 % DNA reassociation, whereas strains identified as biovars 2, 6, 7, 8, 12, 15 and 21 of [P.] aerogenes linked at 81 %. The latter group most likely represents [A.] rossii based on the 16S rRNA gene sequence comparisons. DNA reassociation between the [P.] aerogenes and [A.] rossii groups was at most 37 %, whereas 47 % was the highest DNA reassociation found between [P.] aerogenes and [P.] mairii. The study showed that [P.] aerogenes, [P.] mairii and [A.] rossii can not be easily separated and may consequently be misidentified based on current knowledge of their phenotypic characteristics. In addition, these taxa are difficult to separate from other taxa of the Pasteurellaceae. A revised scheme for separation based upon phenotypic characters is suggested for the three species [P.] aerogenes emend., [P.] mairii emend. and [A.] rossii emend., with the respective type strains ATCC 27883T, NCTC 10699T and ATCC 27072T.

This paper describes a phenotypic and genotypic investigation of the taxonomy of [Haemophilus] paragallinarum, Pasteurella gallinarum, Pasteurella avium and Pasteurella volantium, a major subcluster within the avian 16S rRNA cluster 18 of the family Pasteurellaceae. An extended phenotypic characterization was performed of the type strain of [Haemophilus] paragallinarum, which is NAD-dependent, and eight NAD-independent strains of [Haemophilus] paragallinarum. Complete 16S rRNA gene sequences were obtained for one NAD-independent and four NAD-dependent [Haemophilus] paragallinarum strains. These five sequences along with existing 16S rRNA gene sequences for 11 other taxa within avian 16S rRNA cluster 18 as well as seven other taxa from the Pasteurellaceae were subjected to phylogenetic analysis. The analysis demonstrated that [Haemophilus] paragallinarum, Pasteurella gallinarum, Pasteurella avium and Pasteurella volantium formed a monophyletic group with a minimum of 96.8 % sequence similarity. This group can also be separated by phenotypic testing from all other recognized and named taxa within the Pasteurellaceae. As both genotypic and phenotypic testing support the separate and distinct nature of this subcluster, the transfer is proposed of Pasteurella gallinarum, [Haemophilus] paragallinarum, Pasteurella avium and Pasteurella volantium to a new genus Avibacterium as Avibacterium gallinarum gen. nov., comb. nov., Avibacterium paragallinarum comb. nov., Avibacterium avium comb. nov. and Avibacterium volantium comb. nov. The type strains are NCTC 1118T (Avibacterium gallinarum), NCTC 11296T (Avibacterium paragallinarum), NCTC 11297T (Avibacterium avium) and NCTC 3438T (Avibacterium volantium). Key characteristics that separate these four species are catalase activity (absent only in Avibacterium paragallinarum) and production of acid from galactose (negative only in Avibacterium paragallinarum), maltose (negative only in Avibacterium avium) and mannitol (negative in Avibacterium gallinarum and Avibacterium avium).

Bacteria of the avian [Pasteurella haemolytica]-'Actinobacillus salpingitidis' complex have been associated with different pathological conditions in birds, among which salpingitis and peritonitis in chickens of layer type seem to dominate. The aim of this study was to classify these bacteria by comparison of 37 strains tentatively classified as biovars of the avian [P. haemolytica]-'A. salpingitidis' complex or as Pasteurella anatis. PFGE, AFLP and plasmid profiling showed that strains representing different biovars were genotypically different. Phylogenetic analysis of 22 strains characterized by 16S rRNA gene sequence comparison showed that strains classified as biovars 5, 8 and 9 were closely related to the suggested type strain of 'A. salpingitidis' (98.4-99.9% similarity), whereas the remaining strains classified in 12 biovars or as P. anatis were closely related to the type strain of P. anatis (98.1-100% similarity). The two groups were related at 95.7-97.1% similarity. The closest similarity outside this group was 94.6%, between biovar 15 and Bisgaard taxon 3. DNA-DNA hybridization was performed with 34 strains and showed binding above 85% for strains of biovars 5 and 8, including the suggested type strain of 'A. salpingitidis'. Two strains of P. anatis (F 149T and F 279) were closely related at 79% DNA binding to 27 strains of biovars 1,3, 4, 11, 12, 17-20, 22 and 24. A new genus, Gallibacterium gen. nov., is proposed to include the avian [P. haemolytica]-'A. salpingitidis'-P. anatis complex, since these taxa form a monophyletic unit with similarities above 95% on the basis of 16S rRNA sequence comparison and they are unrelated to other genera of the family Pasteurellaceae Pohl 1981. The new genus consists of Gram-negative, non-motile, rod-shaped or pleomorphic bacteria. The bacteria are catalase-, oxidase- and phosphatase-positive. Nitrate is reduced and acid is produced without gas formation from glycerol, (-)D-ribose, (+)D-xylose, (-)D-mannitol, (-)D-fructose, (+)D-galactose, (+)D-glucose, (+)D-mannose, sucrose and raffinose. The genus Gallibacterium can be separated from other genera of Pasteurellaceae by differences in catalass, symbiotic growth, haemolysis, urease, indole, acid production from (+)D-xylose, (-)D-mannitol, (-)D-sorbitol, (+)D-mannose, maltose, raffinose and dextrin and ONPG and PNPG tests. Pasteurella anatis Mutters et al. 1985 is transferred to the new genus as Gallibacterium anatis gen. nov., comb. nov. Genomospecies 1 of Gallibacterium is proposed to include the former biovars 5 and 8 of the avian [P. haemolytica]-'A. salpingitidis' complex. The type strain of Gallibacterium anatis is F 149T (=ATCC 43329T = NCTC 11413T) and the reference strain of Gallibacterium genomospecies 1 is CCM 5974.

Forty-five strains mainly isolated from chickens in Zimbabwe and Denmark, two pig and three rat isolates all identified as Pasteurella gallinarum by conventional phenotypic tests were characterized by ribotyping, and selected strains were subsequently analysed by 16S rRNA gene sequencing. High genotypic diversity was observed, the number of ribotypes totalling 24. A major group of 47 isolates including the type strain of P. gallinarum clustered at 56% similarity and included 21 ribotypes. Ribotyping showed that some genotypes of P. gallinarum seem to be globally distributed. The three isolates from rodents did not share even a single common ribotype fragment with strains from birds and the pig isolates. Two avian isolates from Denmark and Zimbabwe and the pig strain showed from 97.6 to 99.8% 16S rRNA sequence similarity with the type strain of P. gallinarum and with type strains of Pasteurella volantium and Pasteurella avium. Two rat strains showed 98.6% 16S rRNA gene sequence similarity with each other, but were only related with P. gallinarum at 93% similarity. These isolates showed the highest similarity with [Actinobacillus] muris at 96.4 to 95.0% similarity. We suggest that conventional identification of P. gallinarum consequently should consider the source of isolation to obtain a correct diagnosis, and that isolation from animals other than fowl should be confirmed by genotypic analysis such as 16S rRNA gene sequence comparison.

Objective: To characterise eight isolates of a Gram-negative organism obtained from the upper respiratory tract of cattle showing evidence of mild upper respiratory tract disease., Design: The isolates were compared with the five recognised species within the genus Mannheimia - M haemolytica, M glucosida, M granulomatis, M ruminalis and M varigena--using a range of phenotypic and genotypic methods., Results: Phenotypic characterisation indicated that the isolates belonged to the trehalose-negative [Pasteurella] haemolytica complex. This complex has recently been reorganised into five species within the new genus Mannheimia. Ribotyping performed using HindIII and a computerised analysis system indicated that the eight Australian isolates formed a distinct cluster that was related to, but different from, the five recognised species of Mannheimia. The 16S rRNA sequence of one isolate (BNO311) was determined and a phylogenetic analysis performed. Isolate BNO311 was distinct from the five named Mannheimia spp but did join a larger cluster consisting of rRNA cluster IV (M varigena) and the unnamed rRNA cluster V of Mannheimia. DNA:DNA hybridisation between isolate BNO311 and M haemolytica NCTC 9380T, M granulomatis P411 and Actinobacillus ligniersii NCTC 4189T all suggested similarities of approximately 30%., Conclusions: These phenotypic and genotypic characterisation studies suggest that the eight Australian isolates represent a new species of Mannheimia. Until further characterisation studies are performed, we are unwilling to propose a name for this taxon, preferring to refer to this possible new species as Bisgaard taxon 39 of cluster V of Mannheimia.

One hundred and forty-three Pasteurella spp. strains and 10 unclassified strains obtained from free ranging poultry, dogs and cats were investigated by extended phenotypic characterization. One hundred and forty-nine of these strains were selected for further studies using ribotyping and REA-typing to evaluate the role of dogs and cats in Pasteurella multocida transmission. Seven and six type strains were included for comparison in phenotyping and genotyping, respectively. Eleven clusters and six unclustered strains were revealed by phenotyping. Ribotyping outlined 12 clusters and six unclustered strains. A correlation between clusters obtained by phenotyping and ribotyping was demonstrated which indicated that a genetic basis exists for clusters outlined by quantitative evaluation of phenotypic data. Similarities and differences in hosts, phenotype, ribotype, and zone of isolation were demonstrated among Pasteurella strains investigated. Isolates of P. multocida from ducks were shown to be clonal by both phenotyping and ribotyping. These strains were identical to one of the chickens strains. REA-typing, however, showed that the chicken strain was different underlining that exchange of clones of P. multocida between avian species rarely happens under village conditions. Management practise in the villages suggest the potential for exchange of P. multocida between poultry and animals kept in contact. The present findings, however, did not indicate that clones of P. multocida are widely exchanged between poultry and other animal species, even though close contact exists. In the present investigation exchange of clones of P. multocida was only demonstrated among animals belonging to the same species. Caution is drawn to the use of ribotyping as the sole method for epidemiological typing and tracing of P. multocida. The present results also underline the importance of proper phenotyping in the identification of P. multocida and related species.

Ninety-three trehalose-negative (P.) haemolytica-like strains of ruminant, porcine and leprine origin were investigated. A quantitative evaluation of phenotypic tests was used and the results obtained were compared with those from 246 previously investigated ruminant strains. Cluster analysis of the results obtained displayed most of the taxa as distinct groups which could be related to differences in key characters. Although only minor phenotypic differences were observed between the taxa investigated and the taxa were internally heterogeneous for many of the tests, it was possible to identify characters separating most groups. However, in three instances, taxa isolated from different species could not be separated by any of the tests used or by quantitative evaluation of all 79 tests--the only difference being the species of animals from which they had been isolated. Taxa which could not be separated by phenotypic tests included the ruminant biogroup 6 of (P.) haemolytica and the porcine taxon 15/biovar 1, the ruminant biogroup 7 of (P.) haemolytica and the porcine taxon 15/biovar 2, and ruminant biogroup 31 of (P.) haemolytica and the leprine taxon 20/biovar 1.

Objective: The objective of this work was to perform a comprehensive phenotypic characterisation of 16 isolates of bacteria previously identified as Actinobacillus equuli., Design: The 16 isolates that had been obtained from Australian animals--15 from horses and one from a rabbit--were compared with reference strains of A equuli, A capsulatus, Pasteurella caballi and Bisgaard Taxa 9 and 11., Results: The characterisation study demonstrated that only nine of the isolates were A equuli. The other isolates were identified as A capsulatus (the isolate from rabbit), P caballi (one isolate), Bisgaard Taxon 11 (two isolates) and Bisgaard Taxon 9 (one isolate). The final two isolates could not be assigned to any recognised species or taxa., Conclusion: This study has highlighted the importance of a complete characterisation of Actinobacillus-like organisms isolated from horses and rabbits. The study represents the first time that A capsulatus, P caballi and Bisgaard Taxa 9 and 11 have been recognised as being present in Australia.

Thirty Pasteurellaceae strains isolated from gerbil, guineapig, hamster, mouse, muskrat and rat were reinvestigated and reclassified after comparison with reference strains. Strains originally described as Pasteurella pneumotropica were reclassified as [Pasteurella] pneumotropica Heyl biotype (7), [P.] pneumotropica Jawetz biotype (1), Pasteurella dagmatis (1) or Taxon 22 (2). Strains previously reported as Actinobacillus sp. were reclassified as [P.] pneumotropica biotype Jawetz (3), P. dagmatis (3) or Taxon 6 (7). Strains earlier described as Pasteurella gallinarum were renamed as SP group pasteurella (4) or Taxon 25 (2). Some of these reclassified Pasteurellaceae have not been reported previously in rodents. The present findings underline the importance of extended characterization of isolates and comparison with references strains to avoid misclassification within the family Pasteurellaceae Pohl 1981.

Comparison of phenotypical characters obtained from the type strain of Pasteurella caballi and a previously unclassified P.sp., isolated from an infected wound on a veterinary surgeon, allowed classification of the P.sp. with P. caballi. The P.sp. was isolated in a mixed culture with Escherichia coli and probably represents the first human isolate of P. caballi.

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.

During the present investigation evidence was obtained to indicate that porcine Pasteurella haemolytica-like strains were sufficiently different from P. haemolytica sensu stricto to constitute a new taxon within the family Pasteurellaceae Pohl 1981. Thirteen strains formed a homogenous group tentatively designated taxon 15. The final taxonomical position of taxon 15, however, has to await further taxonomical investigations, including determinations of mol% G+C in DNA and DNA: DNA hybridizations. A species name has not been suggested, for the same reasons.

Genetic investigations of selected bovine and ovine strains of Pasteurella haemolytica sensu stricto (biogroup 1), P. haemolytica biogroups 2, 3, 5 and 9, P. testudinis and porcine isolates of so-called P. haemolytica, tentatively designated taxon 15, confirmed the existence of these phenotypically delineated taxa. Evidence was further obtained to indicate that P. haemolytica biogroups 1, 2, 3, 5 and 9 and P. testudinis constitute a new genus within the family Pasteurellaceae Pohl 1981, and that P. testudinis represents a "missing link" between so-called P. haemolytica biovars A and T. The proposed genus seems to contain several new species. Additional investigations are, however, indicated before final conclusions can be drawn. The authors desist from proposing genus and species names for the same reasons. Porcine strains provisionally named taxon 15 seem to constitute a separate group within the family Pasteurellaceae Pohl 1981, underlining the distinct degree of specificity members of this family show for host species.

The taxonomic relationship of 23 unclassified canine and feline strains of Pasteurellaceae and five strains received as Pasteurella spp. or Haemophilus influenzae-murium was investigated by phenotypic and genetic characterization. Eleven strains were classified with four recently described species of genus Pasteurella sensu stricto. Fourteen canine and feline strains formed a homogeneous group, tentatively designated taxon 16. Both phenotypic characters and mol% G + C in DNA and genome size indicate classification of taxon 16 with genus Pasteurella. DNA/DNA hybridizations, however, failed to locate taxon 16 on genus level with accepted or proposed species of the family Pasteurellaceae Pohl 1981. Two additional species obtained from rats and mice remained unclassified, in addition to a human isolate obtained from a dog-bite. The necessity of detailed phenotypic characterization within the family Pasteurellaceae Pohl 1981 needs to be stressed.

169 strains of P. multocida ssp. multocida, 24 strains of P. multocida ssp. septica, 22 strains of P. multocida ssp. gallicida, and 8 strains of P. avium and P. canis, respectively, were tested for toxin production in EBL-cell culture assay. Toxin production was only demonstrated in strains belonging to P. multocida ssp. multocida. Toxigenic strains were derived from pigs, calves, cats, dogs, rabbits and turkeys.

The taxonomic relationship of 116 isolates of Pasteurella haemolytica was re-investigated by conventional phenotypic characterization. Seventy-nine characters were examined. Ninety strains were classified with previously described biovars of P. haemolytica. The remaining strains made up at least six new biogroups within the P. haemolytica-complex. "Key-characters" separating these groups included ornithine, L(+)arabinose, D(-)sorbitol, cellobiose, beta-glucosidase, glycosides and alpha-fucosidase. The taxonomic significance of these characters is uncertain. Determinations of genome size, mol% G + C in DNA and DNA:DNA hybridizations are in progress to obtain further information on the taxonomic significance of the present findings.

Reinvestigations of 121 strains previously described as Actinobacillus lignieresii showed that only fifteen strains (12%) had phenotypic characters compatible with A. lignieresii sensu stricto. Four strains were diagnosed as Pasteurella multocida and nine strains as P. haemolytica biogroup 1. The remaining organisms had phenotypic characters compatible with Pasteurellaceae, but could not be classified with accepted species. Fifty-one of the strains investigated had phenotypic characters allowing classification with P. haemolytica biogroups 6 through 9. In addition 19 strains made up at least two new biogroups within the bovine and ovine P. haemolytica complex. Twenty-seven unclassified ovine isolates formed a heterogeneous group provisionally designated taxon 18. At least four biovars were demonstrated within taxon 18. The taxonomic significance of characters separating the P. haemolytica complex and taxon 18 as well as characters separating biogroups within these groups remains to be investigated genetically. The necessity of extended phenotypic characterization within the family Pasteurellaceae Pohl 1981 is underlined by the present findings.

During routine bacteriological examination of pneumonic calf lungs it was experienced that many Pasteurella multocida-like isolates had a fermentation pattern different from what is generally accepted for P. multocida sensu stricto. Forty-one out of 50 strains selected for further investigation were phenotypically related and formed a group of indole-, mannitol-and sorbitol-negative P. multocida-like strains, which was tentatively designated taxon 13. Deoxyribonucleic acid/deoxyribonucleic acid hybridizations including both ornithine positive and ornithine negative strains of taxon 13 allowed the classification of the former as P. multocida biovar 6 and the latter as V factor independent strains of Haemophilus avium.

Incorrect diagnosis of species belonging to the family Pasteurellaceae Pohl 1981 is often due to inadequate laboratory identification techniques. Reinvestigations of 56 human isolates of Pasteurellaceae and comparison of the results obtained with those obtained from nine reference strains in 65 different tests allowed classification of 26 strains as P. multocida ssp. multocida, 11 strains as P. multocida ssp. septica, 12 strains as P. canis, 4 strains as P. dagmatis and 1 strain as P. stomatitis. Two strains were tentatively classified with P. haemolytica biogroup 2(T) and the SP-group, respectively. The present investigation also showed that the type strains of P. gallinarum and Haemophilus aphrophilus were phenotypically related. Members of the family Pasteurellacea Pohl 1981 should be considered as potential etiologic agents of any local infection following animal bites or scratches.

Cultural, morphologic, and biochemical characteristics of previously unreported taxa isolated from poultry and tentatively assigned to genus Actinobacillus Brumpt 1910 were compared to those of Actinobacillus lignieresii, A equuli, A. seminis, A. suis, avian haemolytic Actinobacillus sp., A.salpingitidis, avian Pasteurella haemolytica-like strains, P haemolytica biovar T, P, ureae. P. multocida, P. pneumotropica, P. gallinarum and P. anatipestifer. Evidence as obtained to indicate that taxon 1--3 was closely related to genus Actinobacillus Brumpt 1910, but sufficiently different from established species within that genus to constitute new distinct species. Taxon 4 had the cultural and biochemical characters of strains previously described by Clark and Godfrey. Strains designated P haemolytica-like could not be separated from A. salpingitidis on the basis of phenotypical characters. The final taxonomical position of taxon 1-4 in addition to strains designated avian haemolytic Actinobacillus sp. and P. haemolytica-like, however, has to await further taxonomical investigations including determination of mol % G + C in DNA and DNA hybridization, for which reason species names have been omitted.

Abstract Aims: Characterization and classification of members of Pasteurellaceae isolated from birds by extended phenotypic characterization and 16S rDNA gene sequence comparison. Methods and Results: A total of 95 avian isolates were subjected to extended phenotypic characterization. Thirteen bacterial strains selected from main phenotypic clusters and isolated from parrot, parakeet, budgerigar, partridge, pheasant, chicken, duck, hawk and gull were subsequently characterized by 16S rDNA gene sequencing. Eight of the sequenced strains were classified with six taxa of Bisgaard of which two (34 and 40) have not been published before, and the properties of four others (14, 22, 26 and 32) changed upon the characterization of these new isolates. Of the remaining strains, one was identified as a phenotypic variant in maltose and dextrin of Pasteurella gallinarum another as a trehalose positive variant of taxon 3 of Bisgaard. The remaining three strains sequenced were not closely related to existing taxa of Pasteurellaceae . However, they were found to belong to the Avian cluster with 92–97% 16S rDNA gene sequence similarity. Conclusion: The study allowed the classification of bacteria isolated from birds by the integrated use of extended phenotypic characterization and 16S rDNA gene sequence analysis. Only the application of 16S rDNA gene sequencing allows a correct identification of variant strains. Significance and Impact of the Study: The description of new taxa within the bacterial family Pasteurellaceae will subsequently allow additional isolates of these taxa to be identified and improve the diagnosis and epidemiological understanding of bacteria causing disease in birds. [ABSTRACT FROM AUTHOR]

A collection of 43 unclassified members of the Pasteurellaceae, most of which were obtained from lesions, were investigated using an extensive battery of phenotypical tests as well as by ribotyping. The isolates had been made from Anser anser forma (f) domestica (d), Agapornis fischer, Amazona spp., Ara macao, Columba livia f.d., Melanopsittacus undulatus, and Psittacus erithacus. Comparison of results with those obtained from reference strains allowed classification of 25 strains. Three strains were identified as Pasteurella dagmatis, P. sp. A, and [P.] aerogenes, respectively. Twenty strains were classified as taxon 3 and two as taxon 14. Eighteen strains, all originating from psittacine species, belonged to two new taxa, tentatively named Bisgaard taxon 33 and taxon 37. Characters obtained with taxon 33 allowed classification within the family Pasteurellaceae, while the final classification of taxon 37 remains to be investigated. The present investigation underlines the problems confronting diagnostic laboratories attempting to identify members of the family Pasteurellaceae isolated from birds. [ABSTRACT FROM AUTHOR]