Immune responses of cattle following vaccination with living and non-living Babesia bovis antigens.
Twenty-four yearling Hereford (Bos taurus) cattle were vaccinated against Babesia bovis using either live parasites or non-living antigens obtained from the supernatant of in vitro cultures. A single dose of live parasites was given subcutaneously, while the non-living supernatant antigen (NLSA) was combined with saponin and 2 doses given, 2 weeks apart. Following vaccination with live parasites, serum antibodies remained at high levels for 6 months, but the lymphocyte transformation response was low and lasted only 10-18 days. In contrast, NLSA vaccination was followed, after 21-28 days, by a peak of serum antibodies which then slowly declined. The lymphocyte transformation response in these animals was much higher and persisted for 6 months. Following heterologous challenge all unvaccinated cattle had severe reactions and required treatment to prevent death. Cattle vaccinated with live parasites had mild reactions with only 1 of the 12 requiring treatment. Cattle vaccinated with NLSA were only partially protected and 6 of the 12 required treatment.
D000818:Animals; D000917:Antibody Formation; D000953:Antigens, Protozoan / Q000276:immunology*; D001403:Babesia / Q000276:immunology*; D001404:Babesiosis / Q000276:immunology; D002417:Cattle / Q000276:immunology*; D002418:Cattle Diseases / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D008213:Lymphocyte Activation; D014612:Vaccines / Q000276:immunology*; D014613:Vaccines, Attenuated / Q000276:immunology
D000953:Antigens, Protozoan; D014612:Vaccines; D014613:Vaccines, Attenuated