The Enzyme-linked immunosorbent assay (ELISA) was used to detect Ascaris suum antibodies in swine sera with adult body fluid (ABF) as an antigen. The assay was standardized with respect to the antigen concentration and serum and conjugate dilutions. Cross reaction was found between the antigen and the sera from the swine infected with Metastrongylus apri. The ELISA was more sensitive than the complement fixation test. Five protein peaks were obtained from ABF by gel filtration on Sephacryle S-300. Fraction I was the most specific. A 105 kDa protein in the fraction reacted with swine lgG in the serum of infected animals in Western blot analysis.
