University of Arkansas, Fayetteville Division of Agriculture


The efficacy of killed vaccines generally is not equal to live vaccines. However, due to safety and ease of production, they remain a vital part of controlling and preventing diseases. In this study, the immune response to four different vaccination preparation techniques for the agent of bordetellosis of turkeys, Bordetella avium (BA), was compared. Preparation/inactivation techniques included (1) formalin inactivation, (2) opsonization of formalin-inactivated BA, (3) buffered acetic-acid BA inactivation, or (4) opsonization of buffered acetic-acid-inactivated BA. Nonadjuvated suspensions containing equal antigen mass were administered subcutaneously (0.2 mL) at day-of-hatch in all cases. For each treatment (N=40/treatment), plasma samples were obtained on d 6, 10, and 21. Specific antibody titer was determined by enzyme-linked immunosorbent assay (ELISA). Results were analyzed by percentage of responders, calculated by determination of sample-to-positive (S/P) ratio. At d 6, the formalin-killed vaccination caused the most rapid response with significantly higher S/P ratios than other treatments. At d 10 there were no significant differences between the treatments. By d 21, formalin-inactivated antigen produced the highest percentage of responders. In this preliminary experiment, neither buffered acetic-acid BA inactivation nor opsonization of inactivated BA antigen improved turkey poult responsiveness to this pathogen.