Test protocol of an enzyme‐linked immunosorbent assay (ELISA) for the detection of antibodies against bovine leukosis virus

Summary

In this communication the test procedure is described for an indirect enzyme‐linked immunosorbent assay (ELISA) for the detection of antibodies against bovine leukosis virus (BLV). Test sera are incubated in polystyrene microtiter plates sensitized with a partly‐purified preparation of BLV. Bovine antibodies are detected with anti‐species immunoglobulin conjugated to the enzyme horseradish peroxidase, followed by the addition of the enzyme substrate.     

Detection of the K99 antigen of Escherichia coli in calf faeces by enzyme‐linked immunosorbent assay (ELISA)

Summary

An enzyme‐linked immunosorbent assay (ELISA) is presented for the detection of the K99 antigen of Escherichia coli in calf faeces. False‐positive reactions were not observed with K99‐negative strains and with several viral antigens. Only bovine coronavirus caused slight positive reactions which could be eliminated by a blocking test. As compared with the conventional procedure for the detection of the K99 antigen, ELISA seemed to be at least as sensitive and had the advantage that samples could be stored at —20° C before testing. In addition many samples could be handled at the same time and the results became available quickly. By carrying out the assay as a blocking test, specific antibody against K99 in serum or colostrum could be detected and titrated.