Ornithobacterium rhinotracheale gen. nov., sp. nov., Isolated from the Avian Respiratory Tract

Abstract

The phylogenetic position and various genotypic, chemotaxonomic, and classical phenotypic characteristics of 21 gram-negative avian isolates were studied. These strains constitute a genotypically homogeneous taxon in rRNA superfamily V, as shown by DNA-rRNA hybridization data. Determination of the 16s rRNA sequence of this taxon revealed its detailed position within the "flavobacter" subgroup of the "flavobacter-bacteroides" phylum as described by Gherna and Woese (R. Gherna and C. R. Woese, Syst. Apple Microbiol. 15513-521, 1992). This new taxon is only distantly related to other members of the "flavobacter-bacteroides" phylum and is therefore given separate generic status. The DNA-DNA binding values for members of this taxon, for which we propose the name Ornithobacterium rhinotracheale, confirmed that all of the strains are highly interrelated (DNA-DNA binding values greater than 90% were measured). The G+C contents of members of this taxon are between 37 and 39 mol%, An analysis of the cellular proteins and fatty acids and classical phenotypic characteristics allowed us to distinguish 0. rhinotracheafe from phenotypically similar taxa, such as Riemrelliz anatipestiyer and Capnocytophaga species. The respiratory quinone content (menaquinone 7) and carbohydrate pattern of 0 . rhinotracheale conform with the respiratory quinone contents and carbohydrate patterns of other members of rRNA superfamily V.In the past decade, we determined the protein and fatty acid profiles of a large number of avian isolates which could not be classified after primary identification tests were performed in veterinary laboratories. A total of 21 of these isolates had very similar profiles and differed clearly from all of the other strains investigated, including reference strains of well-known fowl pathogens. These 21 strains were isolated from the respiratory tracts of turkeys (10 strains), chickens (7 strains), rooks, (3 strains), and a partridge (1 strain). Clinical data were not available for all of these strains. However, most of the strains were associated with various respiratory tract infections, including tracheitis, pericarditis, sinusitis, airsacculitis, and pneumonia. Preliminary data on some of the chemotaxonomic characteristics of four strains have been described previously (36).We studied a wide range of taxonomic parameters, including genotypic, chemotaxonomic, and classical phenotypic parameters, in order to establish the phylogenetic affiliation and to comprehensively describe the new taxon, for which we propose the name Omithobacterium rhinotracheale. Special emphasis was given to the differentiation of 0. rhinotracheale, Riemerella anatipestifer, and Capnocytophaga species as these taxa share a number of phenotypic characteristics. * Corresponding author. Mailing address: Laboratorium voorMicrobiologie, Universiteit Gent, K. L. Ledeganckstraat 35, B-9000 Gent, Belgium. Phone: 32-9-2645114. Fax: 32-9-2645346. MATERIALS AND METHODSIsolation of 0. rhinotracheale strains. Samples were inoculated onto media routinel...

Investigations on ornithobacterium rhinotracheale in broiler flocks in elazig province located in the east of turkey

“…This finding is in agreement with the results reported by Vandamme et al (1994), Amonsin et al (1997, Lopes et al (2000) and Hung and Alvarado (2001) who showed a high similarity levels between the total protein profiles and the outer membrane protein (OMP) profiles of ORT isolates despite differences in their origin and/or serotype. The high similarity among total protein and OMP profiles indicates that the isolates originating from all the over the world and from several bird species are represented by a small group of closely-related clones .…”

NOTES: New Perspectives in the Classification of the Flavobacteria: Description of Chryseobacterium gen. nov., Bergeyella gen. nov., and Empedobacter nom. rev.

“…One of the main conclusions of these studies is that the genera Flavobacterium, Cytophaga, and Flexibacter all are polyphyletic and should be redefined and subdivided into several genera. The relationships of these taxa to other members of this rRNA superfamily, such as the genera Capnocytophaga, Omithobacterium, Riemerella, and Weeksella, have been described in several papers (10,25,28,33) and are partially shown in Fig. 1 none of the four natural groups described above is closely related to F. aquatile.…”

Pathological study on the upper respiratory tract infection of chickens and isolation, identification of causal bacteria

“…Escherichia coli are also associated with respiratory infection in chickens (Sukhon et al, 2002). Ornithobacterium rhinotracheale has recently been identified as causing respiratory tract infections in poultry and other birds (Vandamme et al, 1994;Chin et al, 2003). Concurrent infection of young poultry with Klebsiella pneumoniae increased the severity of respiratory disease .…”