De Vos A J, Bessenger R, Fourie C G
Onderstepoort J Vet Res. 1982 Sep;49(3):133-6.
A South African Babesia bovis strain showed loss of virulence after 10 rapid passages in splenectomized calves. The virulence was comparable with that of an attenuated Australian vaccine strain. Vaccination of cross-bred Bos indicus cattle with the local strain resulted in a solid immunity to heterologous challenge. The degree of protection afforded by the Australian vaccine strain was adequate for controlling challenge with a virulent South African strain, but somewhat less than the degree conferred by the local vaccine strain. Serological observations with the indirect fluorescent antibody test confirmed a close relationship between the 2 modified strains.
一株南非牛巴贝斯虫在脾切除的犊牛体内经过10次快速传代后毒力丧失。其毒力与澳大利亚减毒疫苗株相当。用本地菌株对杂交瘤牛进行疫苗接种可使其对异源攻击产生稳固的免疫力。澳大利亚疫苗株提供的保护程度足以控制南非强毒株的攻击，但略低于本地疫苗株提供的保护程度。间接荧光抗体试验的血清学观察证实了这两种改良菌株之间的密切关系。
