Development of an enzyme-linked immunosorbent assay for Bordetella avium

A Bordetella avium enzyme-linked immunosorbent assay (ELISA) was developed to detect serum antibodies in 1-day-old poults, experimentally infected turkeys, and naturally infected turkeys. The optimized procedure included use of a suspension of whole bacteria coated onto plastic microtiter plates, a 1:200 serum dilution, a 1:3200 dilution of commercially available goat anti-turkey IgG (heavy and light chain) conjugated with horseradish peroxidase, and 0.04% orthophenylenediamine as substrate. A sample/negative (S/N) ratio method of analysis was used to estimate antibody titer from absorbance values. The regression equation used to estimate antibody titers was derived from the testing of naturally infected turkey sera. The equation was derived by plotting the log10 titer of the sera against the S/N ratio at a 1:200 serum dilution. The ELISA was an effective method for detecting antibody to B. avium, and the procedure should prove useful for laboratories equipped for high-volume ELISA testing.