Mafra C L, Patarroyo J H, Silva S S
Departamento de Medicina Veterinária, Universidade Federal de Viçosa, MG, Brazil.
Vet Parasitol. 1994 Mar;52(1-2):139-43. doi: 10.1016/0304-4017(94)90043-4.
In order to verify the infectivity and transovarian transmission of one strain of Babesia bovis of Brazilian origin, attenuated by repeated passages in splenectomized calves to the biological tick vector, Boophilus microplus, an inoculation of that strain was performed in hemoparasite-free calves infested with hemoparasite-free ticks. Subsequently, engorged female ticks were collected to examine hemolymph and progeny for presence of developing stages of Babesia bovis. Using an optical microscope, intrahemocytic merozoites were observed in female hemolymph on the second and fourth days, respectively, after ticks dropped from calves. By histological observation of F1 larvae, after more than 24 h of adherence on calves, sporokinetes and small merozoites were present in the samples of hemolymph. These results confirmed the maintenance of infectivity by the vaccine strain attenuated after 26 passages for tick Boophilus microplus.
为了验证源自巴西的一株牛巴贝斯虫的传染性和经卵传递特性，该毒株经在脾切除小牛体内反复传代致弱后接种到生物蜱传播媒介微小牛蜱上，将该毒株接种到无血液寄生虫且感染无血液寄生虫蜱的小牛体内。随后，收集饱血雌蜱，检查其血淋巴和后代中是否存在牛巴贝斯虫的发育阶段。使用光学显微镜，分别在蜱从小牛身上掉落的第二天和第四天，在雌蜱血淋巴中观察到血细胞内裂殖子。通过对F1幼虫的组织学观察，在幼虫附着于小牛超过24小时后，血淋巴样本中存在子孢子和小裂殖子。这些结果证实了经26代传代致弱后的疫苗株对微小牛蜱仍保持传染性。
