Babesia divergens in splenectomised calves: immunogenicity of lyophilised plasma from an infected animal.

An experiment was carried out in which three groups of splenectomised calves were inoculated on three occasions at fortnightly intervals with lyophilised plasma from an animal reacting to Babesia divergens infection. Two weeks later these three groups of calves, together with three control groups, were challengpd with isologous, homologous or heterologous isolates of B divergens. Limited protection to isologous and homologous challenge was observed in the calves inoculated with plasma.