Early diagnosis of enzootic bovine leukosis.

Abstract

For establishment of early diagnosis of enzootic bovine leukosis (EBL), the complement-dependent antibody cytotoxicity (CDAC) test using monoclonal antibody against tumor-associated antigen (TAA) expressed on EBL tumor cells, lymphocyte counts, lactate dehydrogenase (LDH) activities and concentration of serum sialic acid (SA) were examined in clinical subclinical and EBL cases. In TAA-positive clinical and subclinical cows, lymphocyte counts, total LDH, LDH2 and LDH3 activities and concentration of SA increased, whereas LDH1 activity decreased from those of TAA-negative healthy cattle. The cytotoxic index (CI) values of the CDAC test from individual cows examined were compared with the results of other clinical examinations. Significant correlation coefficients were observed between CI values and the lymphocyte counts, total LDH, LDH1 and LDH2 activities and concentration of SA (p<0.05-0.005).