Campylobacter fetus diagnosis: Direct immunofluorescence comparing chickenIgY and rabbit IgG conjugates

In Argentina Bovine Genital Campylobacteriosis is routinely diagnosed by di rect immunofluorescence test. Generally, the hyperimmune sera used for this test are obtained from rabbits and less often from goats. In this work, a chicken egg yolk immunoglobulin (IgY) extract was conjugated and its abilit y to detect campylobacters with the regular conjugate prepared with rabbit sera was comparatively evaluated. Both conjugates were independently evalua ted by two laboratories, named "Azul" (Lab A) and "Balcarce" (Lab B). Anima ls were immunised with formalin inactivated Campylobacter (C.)fetus cells. Chic-ken IgY and rabbit IgG were conjugated with fluorescein isothiocyanate and used to comparatively examine strains of C. fetus subspp., other Campy lobacter spp. and different bacterial species. Both conjugates had a high p ercentage rate of detection for C. fetus. IgY had less background due to un specific fluorescence than IgG. IgY is a cheap, bloodless and very producti ve method. IgY can replace mammal immunoglobulins for C. fetus diagnosis.