LACK OF PROTECTION AGAINST AVIAN CHOLERA BY VACCINATION WITH RECOMBINANT PG-LIKE PROTEIN FROM PASTEURELLA-MULTOCIDA

The gene encoding the P6-like protein of Pasteurella multocida was clo ned in the baculovirus expression system. Baculovirus-expressed recomb inant protein was used to parenterally immunize 6-wk-old Nicholas broa d-breasted white turkeys. Turkeys developed significant antibody titer s to the recombinant protein as measured by enzyme-linked immunosorben t assay. Two weeks after the last immunizing injection, vaccinated tur keys were placed in contact with turkeys infected with P. multocida st rain P1059, as were nonvaccinated control birds. No differences occurr ed in percent mortality between the two groups. We conclude that paren terally administered recombinant P6-like protein does not protect turk eys from avian cholera.