A pathogenic challenge model for adult northern bobwhite (Colinus virginianus) using a vaccine strain of Pasteurella...

A pathogenic challenge model causing approximately 50% mortality was developed in adult Northern bobwhite (Colinus virginianus) using Avichol, a live vaccine containing the Clemson University (CU) strain of Pasteurella multocida Type 3. A dose of 2300 or 3000 colony-forming units (CFU) of Avichol injected intramuscularly resulted in 30 to 75% mortality, whereas a dose of 230 CFU or less resulted in no mortality, and 58,720 CFU or more resulted in death in all birds challenged. Primary and secondary vaccination of Northern bobwhite with a formalinized anaculture of Avichol -derived P. multocida resulted in protection against challenge in three separate experiments. Dexamethasone treatment of birds during vaccination resulted in decreased protection against challenge exposure.