Submitted to: Avian Diseases
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 26, 1997
Publication Date: N/A
Interpretive Summary: Bordetella avium causes turkey coryza, a respiratory disease of major importance to the poultry industry. Vaccines, containing antigens responsible for attaching the bacteria to the respiratory tract, are thought to induce protection against the disease by producing antibodies that prevent bacterial colonization. Other antigens, such as toxins, may be involved in vaccine protection against clinical signs of the disease. This study was done to determine whether antibodies against the whole bacteria and a lethal toxin would protect turkeys against colonization by Bordetella avium and against clinical signs of the disease. Antibodies against the whole bacteria protected turkeys against clinical signs but did not protect the respiratory tract from colonization with Bordetella avium. Antibodies to the toxin neither protected the respiratory tract from colonization nor protected against clinical signs of the disease. These findings showed that antigens other than toxin or those that promote respiratory tract attachment are responsible for protection. This information will be useful in developing new and better vaccines and strategies to control turkey coryza.
Technical Abstract: Antisera made against whole cells of Bordetella avium protected turkeys against disease signs of turkey coryza, but antiserum against the dermonecrotic heat-labile toxin (DHLT) did not. Neither antiserum against whole cells nor antiserum against DHLT protected turkeys against colonization of the trachea by B. avium. At least 25 bands in whole-cell lysate of B. avium separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) reacted in immunoblots with protective antiserum. These bands occurred at <40 kDa and >105.5 kDa. DHLT had an isoelectric point in the range pH 6.3 to 6.7. Following SDS-PAGE of isoelectric focused fractions, two bands were recognized by anti-DHLT with immunoblots of pI 6.3, pI 6.5 and pI 6.7 fractions separated by SDS-PAGE.