Thillai Koothan, PRatnam, SVenkatesan, RATANUVAS2022-07-112022-07-111987https://krishikosh.egranth.ac.in/handle/1/5810185386TNV_CRN_1987_16(5)214-219Dark-field microscopy and immunoperoxidase staining test for the demonstration of antigen and microscopic agglutinatian (MAT) and enzyme linked immunosorbant assay (ELISA) for the demonstration of antibody were compared in experimentally infected calves with scrovars Pomona and autumnalis. The darkfield microscopy was found better than the immunopcroxidase staining both in blood and urine samples Second centrifugation at l0000G always gave higher positive results. {The MAT detected early serum antibodies than the ELISA The late antibody detection by ELISA may probably be due to the use of IgG fraction in the conjugate The ELISA exhibited higher level of titres than MAT.EnglishVeterinary ScienceArticle