Abstract
Antigens of Eimeria tenella sporulated oocysts were applied to detect serum antibody of calf infected with Eimeria. Polypeptides of E. tenella oocyst were strongly proved with the infected bovine serum in immunoblotting. The infected serum also showed higher absorbances than that of normal serum in enzyme linked immunosorbent assay (ELISA) using E. tenella oocyst antigen. Suitable conditions for the ELISA were obtained by using soluble antigen of E. tenella oocysts at 2.5μg/ml and bovine serum at 200 fold dilution.