National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido, 080-8555, Japan.
Parasitol Res. 2012 Sep;111(3):1259-66. doi: 10.1007/s00436-012-2960-4. Epub 2012 May 29.
Although Babesia bovis and Babesia bigemina infections cause economic losses in the cattle industry in northern Thailand, there is inadequate information on Babesia isolates present in the area. Therefore, to determine the prevalence and genetic relationship between Babesia isolates, we screened 200 blood samples of cattle from Chiang Rai, Chiang Mai, and Lumpang provinces of northern Thailand. A nested polymerase chain reaction using primers targeting B. bovis spherical body protein 2 (BboSBP2) and B. bigemina rhoptry-associated protein 1a (BbiRAP-1a) genes revealed a prevalence of 12 and 21 % for B. bovis and B. bigemina, respectively, while that of mixed infections was 6.5 % samples. The prevalences of B. bovis in Chiang Rai, Chiang Mai, and Lumpang were 9.5, 3.7, and 25.5 %, respectively. For B. bigemina, the prevalences were 15.8, 12.9, and 39.2 % in Chiang Rai, Chiang Mai, and Lumpang, respectively. Mixed infections with B. bovis and B. bigemina were 6.3 % in Chiang Rai, 1.9 % in Chiang Mai, and 13.7 % in Lumpang. The identical sequences of either BboSBP2 gene or BbiRAP-1a gene were shared among the Babesia isolates in the three provinces of northern Thailand. Further analysis using the internal transcribed spacer gene revealed at least four genotypes for B. bovis and five genotypes for B. bigemina in northern Thailand, while the sequences present great genetic diversities in the different isolates. Overall, we have demonstrated a high prevalence and polymorphism of Babesia parasites in northern Thailand calling for the need to design effective control programs for bovine babesiosis.
尽管布氏巴贝斯虫和双芽巴贝斯虫感染给泰国北部的养牛业造成了经济损失，但该地区存在的巴贝斯虫分离株的信息不足。因此，为了确定巴贝斯虫分离株的流行情况和遗传关系，我们对来自泰国北部清莱府、清迈府和廊开府的 200 份牛血样进行了筛查。使用针对牛巴贝斯虫球形体蛋白 2（BboSBP2）和双芽巴贝斯虫伸头相关蛋白 1a（BbiRAP-1a）基因的巢式聚合酶链反应显示，B. bovis 和 B. bigemina 的流行率分别为 12%和 21%，而混合感染的流行率为 6.5%。在清莱府、清迈府和廊开府，B. bovis 的流行率分别为 9.5%、3.7%和 25.5%。对于 B. bigemina，流行率分别为 15.8%、12.9%和 39.2%。在清莱府、清迈府和廊开府，B. bovis 和 B. bigemina 的混合感染率分别为 6.3%、1.9%和 13.7%。BboSBP2 基因或 BbiRAP-1a 基因的相同序列在泰国北部三个省的巴贝斯虫分离株中共享。进一步使用内部转录间隔区基因分析表明，泰国北部至少存在 4 种 B. bovis 基因型和 5 种 B. bigemina 基因型，而不同分离株的序列存在很大的遗传多样性。总体而言，我们已经证明了泰国北部巴贝斯虫寄生虫的高流行率和多态性，这需要设计有效的牛巴贝斯虫病控制方案。
