Serological reactivity of duck sera to three electrophoretically characterized extracts of Aspergillus

Three different antigens, whole culture, cell sap shaker culture and culture filtrate extracts of Aspergillus were characterized by crossed immunoelectrophoresis. Thirteen to fifteen precipitin lines were produced with their homologous antisera. Application of these extracts to the assay of wild duck sera showed that the whole culture extract was the most sensitive of the three antigens in detecting antibody. Countercurrent immunoelectrophoresis, used with a modified buffer, produced results comparable in sensitivity to immunodiffusion in detecting avian antibody.