Z-014. Molecular Characterization and Genetic Diversity of Ornithobacterium rhinotracheale Strains Isolated in Taiwan

C-H. Chou, S-Y. LIN, H-J. Tsai;
Natl. Taiwan Univ., Taipei City, TAIWAN.

Ornithobacterium rhinotracheale (ORT) is a bacterium common to commercial poultry and wild birds throughout the world. In Taiwan, ORT has been isolated from chickens, pigeons, and turkeys. It is also known as a causative agent of respiratory diseases. In this study, ORT tracheal swabs were collected from different avian species for isolation between 2004 to 2006. The isolated ORT strains of each species (chicken, pigeon, ostrich, quail, turkey and Asian Crested Goshawk [Accipiter trivirgatus]) were further differentiated by molecular typing methods including 16S rRNA sequence, random amplified polymorphic DNA (RAPD), and single enzyme amplified fragment length polymorphism (SE-AFLP). In the results of 16S rRNA sequence, high genetic similarity (97-100%) was revealed except for the chicken-origin isolates from Yunlin county, pigeon-origin and turkey-origin isolates which were also divided into different clusters within the phylogenetic tree. In order to investigate the genetic polymorphysm among the ORT isolates, SE-AFLP and RAPD methods were conducted and analyzed with the ATCC 51464 strain. The result showed that the DNA patterns of chicken-origin and quail-origin isolates were different from those of ostrich-origin, pigeon-origin and Asian Crested Goshawk-origin isolates but identical to partial turkey-origin isolates. Based on the feature that different-origin ORT isolates were separated by the AFLP and RAPD methods, it is suggested that intraspecific differerce within species Ornithobacterium or even species other than Ornithobacterium may exist. These results demonstrate a different variability of ORT from Taiwan, and both RAPD and SE-AFLP provide information on intraspecific differences which will be useful for molecular epidemiological or ecological studies.