Ornithobacterium rhinotracheale infection in turkeys: Immunoprophylaxis studies

Ornithobacterium rhinotracheale has been shown to cause serious clinical il lness and is a significant concern to the turkey industry because of its po tential economic impact. In this study, 6-wk-old turkeys were vaccinated in tranasally with a live or subcutaneously with a killed O. rhinotracheale va ccine. At 14 or 21 wk of age, the birds were challenged intratracheally wit h live O. rhinotracheale. Airsacculitis and pneumonia occurred less frequen tly in vaccinated birds than in unvaccinated birds after challenge with O. rhinotracheale. Ornithobacterium rhinotracheale was recovered from unvaccin ated, challenged birds but not from vaccinated, challenged or from unchalle nged birds. Thus, turkeys inoculated with live or killed O. rhinotracheale vaccine were protected from pathologic changes.