INFLUENCE OF DIFFERENT TREATMENTS OF EGG-YOLK ONTO THE MEASURE OF ANTIBODY-TITERS TO 4 AVIAN VIRUSES BY ELISA

This study was undertaken to evaluate the antibody egg yolk titers fir st without extraction from the lipids of the yolk by the chloroform, s econdly after different dilutions of the yolk, thirdly with just a par t of the yolk instead of the homogeneized yolk and lastly after congel ation of the yolk. Commercially ELISA kits were used to measure the an tibody titers to each of the following viruses : Infectious bursal dis ease virus, Infectious bronchitis virus, Newcastle disease virus and v iral arthritis virus. This study has shown that it is possible to meas ure the antibody egg titer without extraction from the lipids. The con gelation has not modified the antibody titers with or without extracti on at the dilution 1 :10. On the contrary the decongelation of egg yol k at the dilution 1 :2 has so much modified the consistance of yolk th at it became impossible to titer the antibodies securely. As to the us e of a small quantity of egg yolk instead of the homogeneized yolk, if it is statistically possible, we considered that this type of samplin g is not enough reliable.