Etiopathogenesis and diagnostics of avian ornithobacteriosis

Abstrakt

Avian ornithobacteriosis (ORT) is a disease entity associated with respiratory system, most often reported in chickens and turkeys. The etiologic agent of ORT is Gram-negative rodshaped bacterium which after a detailed phenotypic and genotypic analysis performed by Vandamme was given the name Ornithobacterium rhinotracheale in 1994. This fact contributed to marked growth of Ornithobacterium rhinotracheale isolation and identification number worldwide. In Poland, the first isolations were recorded in 1995 from turkeys with respiratory disease symptoms. The optimal growth of these organisms is obtained when they are incubated on 5% sheep blood agar for at least 48h at 37°C under the micro-aerophilic conditions (5–10% CO₂). This disease may affect chickens and turkeys at any age, the birds manifest dyspnoea, sneezing, increased mortality rate and decreased egg production. Currently, 18 serotypes of ORT have been differentiated (from A to R). Owing to hardships in Ornithobacterium rhinotracheale isolation, efficient detection of the infected flocks is realized through serologic monitoring of ORT by the ELISA test. The direct diagnostics with PCR assays also proved extremely useful for identification purposes.