Serum of Boophilus microplus infested cattle reacts with different tick tissues.

Five cattle were each experimentally infested with 30,000 Boophilus microplus larvae and their humoral immune response to salivary gland, gut, embryo and larval extracts during infestation were determined by enzyme-linked immunosorbent assay (ELISA) and Western blot analysis. Serum antibodies to embryo extract were detected by ELISA 21 days after infestation and antibodies to the other extracts 28 days following infestation. Using Western blot analysis, new bands were recognized and others disappeared during infestation. One low molecular weight band (10,000) was detected in embryo extract 14 days after infestation and in other extracts 28 days after infestation; another band (12,000 mol. wt.) in embryo, larval and salivary gland extracts was detected at the same time as the 10,000 mol. wt. band. These results suggest that common antigens are present in different tissues of B. microplus.