Antibody kinetics in response to vaccination against Babesia bovis

The kinetics of specific indirect fluorescent antibody (IFA) test titers and total serum immunoglobulin (Ig) G and IgM values were determined in cattle vaccinated with culture-derived soluble Babesia organisms. Nineteen days after challenge exposure (postinoculation day 67), vaccinated cattle had a strong anamnestic response and mean IFA titers reached 1:48,710. Serum IgG and IgM concentrations were increased after vaccination and after challenge exposure. A nonspecific suppression of total IgG (controls) and IgM (vaccinated animals and controls) values also was observed, the depression coinciding with the period of peak parasitemia.