Sixty-one avian strains of Pasteurella multocida were characterised and compared by biochemical tests, capsular PCR typing and ERIC-PCR. The strains were recovered from various avian species (goose, duck, Muscovy duck, turkey, chicken and pheasant) and represented different geographic locations in Hungary. Forty-two strains (69%) were identified as P. multocida subsp. multocida and 19 strains (31%) as P. multocida subsp. septica. The strains were grouped into 7 different biovars (1, 2, 3, 4, 5, 6 and 7). The most prevalent biovars were 1 (25%), 3 (21%) and 6 (21%). Most of the duck isolates (90%) belonged to biovar 1 or 6. The most frequent capsular type was A (93.5%). Type F represented only a small number (6.5%) of the strains. Other capsular types were not identified. From the 61 isolates 24 different fingerprint patterns were generated by ERIC-PCR assay. Based on cluster analysis the strains could be grouped into four larger and four miniclusters that showed considerable correlation with the geographical origin and the host species. The results indicate that ERIC-PCR may be a suitable technique for studying the host adaptation of P. multocida and the epidemiology of fowl cholera. Key words: Pasteurella multocida, poultry, capsular type, biovar, ERIC-PCRPasteurella multocida is a Gram-negative, non-motile, non-spore-forming, facultative anaerobic bacterium that can infect a wide range of wild and domesticated mammals and avian species, causing a variety of diseases. As a primary infectious agent it is responsible for fowl cholera in poultry (Rimler and Rhoades,

Pasteurella multocida causes infectious diseases in a wide range of animal species. Antimicrobial therapy is still an effective tool for treatment. Generally, P. multocida isolates are susceptible to most of the widely used commercial antimicrobial agents but their excessive and unjustified use accelerates the emergence of resistant strains. We defined the antimicrobial sensitivity pattern of 56 P. multocida strains isolated from poultry (20) and swine [16 P. multocida toxin (PMT) positive and 20 PMT negative] to 16 widely applied antibiotics (apramycin, cefquinome, chloramphenicol, colistin, doxycycline, enrofloxacin, erythromycin, florfenicol, flumequine, neomycin, oxolinic acid, penicillin, trimethoprim potentiated sulphamethoxazole, sulphonamide compounds, tetracycline, tulathromycin) by the disk diffusion method. The majority of the strains was susceptible to most of the antimicrobial agents tested. However, the resistance to sulphonamides, tetracyclines, first-generation quinolones and aminoglycosides was remarkable, and thus the use of these compounds for the treatment of infection caused by P. multocida is not recommended. On the other hand, the antimicrobial activity of the classical penicillin, the newer macrolide (tulathromycin), the third-generation fluoroquinolone (enrofloxacin) and the fourth-generation cephalosporin (cefquinome) proved to be satisfactory against this bacterium.

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A total of 146 Pasteurella multocida strains isolated from swine in Hungary in the last 20 years were examined. Biochemical characterisation and PCRbased techniques were used to determine species, subspecies, biovar, capsule type and presence of the toxA gene. Eighty-seven percent of the isolates belonged to P. multocida ssp. multocida, and 98% of these had biovar 3 or were trehalose-or lactose-fermenting or ornithine decarboxylase negative variants of that. Ten percent of the strains were P. multocida ssp. septica, and within this group 80% of the strains showed sorbitol-negative biovars (5, 6 and 7). The rest of the strains (20%) were lactose positive. Only 3% of the porcine isolates were P. multocida ssp. gallicida and 3 out of the 4 strains belonged to the dulcitol-fermenting biovar 8. Using a capsule-specific multiplex PCR, 60% of the strains belonged to capsule type D, 38% to capsule type A, and only 1 isolate had capsule type F. In contrast with data published in the literature, only 3% of capsule type D isolates carried the toxA gene, while this ratio was 41% for the type A strains. A remarkable regional distribution of toxA gene positive strains was observed. All but two isolates were found in swine herds located in the Transdanubian region, separated from other parts of Hungary by the river Danube.

Abstract. Pasteurella multocida is the causative agent of fowl cholera in domesticated and wild birds. The disease outcome is affected by various host-and pathogen-specific determinants. Several putative virulence factors have been proposed to play a key role in this interaction, including the ptfA gene, the products of which assemble to form type 4 fimbriae on the bacterial surface. One way to understand more precisely how ptfA contributes to pathogenesis is to gather molecular features of this gene in circulating avian P. multocida strains. Therefore, molecular characterization of the ptfA gene of P. multocida strains isolated from domestic poultry was performed using the combination of nucleotide sequence analysis and a newly developed allelespecific polymerase chain reaction assay. Two major ptfA alleles were identified among 31 strains, representing various serogroups and somatic serotypes. It was noteworthy that allele specificity and case severity of a subset of strains correlated with the available gross pathology data. Therefore, the acquisition of comprehensive clinical and epidemiological data together with molecular characteristics of individual strains will help to design and implement adequate preventive and intervention strategies.

Thanks to its small size, external fertilization and fecundity, over the past four decades, zebrafish (Danio rerio) has become the dominant fish model species in biological and biomedical research. Multiple lines of evidence, however, suggest that the reliance on only a handful of genetic model organisms is problematic, as their unique evolutionary histories makes them less than ideal to study biological questions unrelated to their historically contingent adaptations. Therefore, a need has emerged to develop novel model species, better suited for studying particular problems. The paradise fish (Macropodus opercularis) has a much more complex behavioral repertoire than zebrafish and has been a favored model animal in ethological research during the last decades of the previous century. We believe that with currently available, easily adaptable genetic toolkits, this species could be easily developed into a popular model of behavioral genetics. Despite its earlier popularity, however, the description of a detailed housing and husbandry protocol for this species is still missing from scientific literature. We present here a detailed description of how to raise and breed paradise fish successfully under laboratory conditions, and also discuss some of the challenges we faced while creating a stable breeding population for this species in our facility.

During a general annual fish health survey in natural waters and ponds, epitheliocystis infections were recorded in fingerlings of two cyprinid fish species, the cultured common carp and the wild gibel carp. Benign and heavy infections were equally observed without mortality. In addition to the general health inspection of fish, histopathological examinations of infected gills and molecular biological investigations of separated epitheliocysts were performed. Epitheliocysts were formed both in the interlamellar epithelial cells and in the lamella-free multilayered epithelium of the gill filaments. At the early stage of infection darkstaining inclusion bodies densely stuffed with some pathogenic agents were located at the centre of the cell, while in a progressive stage of the process inclusion bodies within the host cells were disseminated in the cytoplasm and stained pale. Molecular studies demonstrated three different agents related to Neochlamydia, Protochlamydia and Piscichlamydia based on sequence analysis of short regions of the 16S rRNA gene. Among them, Piscichlamydia is a primary fish pathogen, while Neochlamydia and Protochlamydia mostly infect free-living amoebae but have adapted thoroughly to fish.

Thirteen Corynebacterium pseudotuberculosis biotype ovis strains isolated from clinical cases of caseous lymphadenitis in Hungary were characterised using multilocus sequencing and their phylogenetic comparison was carried out on the basis of four housekeeping genes (groEL1, infB, dnaK, and leuA). The in silico analysis of the 16 frequently studied housekeeping genes showed that C. pseudotuberculosis strains could be readily distinguished from C. diphtheriae and C. ulcerans strains; however, sequences of the same genes in the two biotypes of the C. pseudotuberculosis were highly similar; the heterogeneity values were low. Genes dnaK, infB, groEL1, and leuA showed marked genetic variation within C. pseudotuberculosis, and strains of the two biotypes of C. pseudotuberculosis could be differentiated. Analysis of the individual genes showed a fairly conservative nature of C. pseudotuberculosis biotype ovis strains. The greatest genetic differentiation was seen in the dnaK and infB genes and concatenations of these two genes were very useful in the genetic separation of the studied strains.