Countermeasures to Prevent and Control Respiratory Pathogens of Poultry

Approach: For the first stated problem, proteomic techniques will be used to identify important, immunoreactive protein antigens. Proteomic techniques have been successfully used by scientists in our Research Unit to identify important diagnostic as well as potential vaccine antigens. For the second identified problem, a genomics approach will be used in attempting to improve the limit of detection for a previously developed, highly sensitive and specific PCR for B. avium. Also, a PCR-based test will be developed for O. rhinotracheale as no diagnostic tests are currently available for this newly emerging pathogen. For the third identified problem two approaches will be pursued. The first approach will include the development of improved live, non-virulent, modified P. multocida strains based on deletions of known virulence factors already under development by scientists in our Research Unit. The second approach will include development of a non-living vaccine for P. multocida, based on the promising new bacterial ghost technology, originally developed by European scientists. This technology is based on the ability of a phage lysis protein, for which the corresponding gene has been previously cloned into the selected pathogen, to form pores in the bacterial cell membrane. Cytosolic contents are extruded through the pores, resulting in empty, but intact, non-living bacterial shells containing important antigenic determinants.