Characterization of Ornithobacterium rhinotracheale Isolates from Commercial Chickens

Ornithohac/erium rhino/rachea/e (ORT) is a relatively rceently diseovered bacterium. which it is associated with respiratory diseases, Tracheal samplcs from carcasses of 100 roultry tlocks submitted to Razi Institute were examined for ORT isolation. Ali these tlocks were affected with respiratory disorders. Colonies of ORT were detected after 24h of incubation and identification of ORT isolates were carried out based on the biochemical and serologie al charaeteristics. Fitiy-nine isolates From broilers, broiler breeders, and layer Ilocks were idcntilied as ORT and analyzed for serotyping. The isolates were identified as serotype A. using standard • antisera againsl ORT anligens in rapid slide agglutination, agar gel precipitation and immunodot tests. The identification of the species was confirmed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis of whole cell proteins. High similarity ofprotein profiles of the isolates was observed. These preliminary results establish that ORT serotype A is associated with outbreaks ofrespiratory diseases in commercial poultry.