Yin Hong, Schnittger Leonhard, Luo Jianxun, Seitzer Ulrike, Ahmed Jabbar S
Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu, China.
Parasitol Res. 2007 Sep;101 Suppl 2:S191-5. doi: 10.1007/s00436-007-0689-2.
A fatal disease of sheep and goats in the northwestern part of China has in the past been reported to be due to Theileria lestoquardi. However, some characteristics of the causative agent are not in accordance with attributes ascribed to this parasite. We therefore determined the nucleotide sequence of the 18 small subunit ribosomal RNA (18S rRNA) gene of T. lestoquardi and the parasite identified in China and compared it with that of other Theileria and Babesia species. In the inferred phylogenetic tree, the 18S rRNA sequence of the Chinese parasite falls inside the clade consisting of Theileria species evidencing that it belongs to this genus. The 18S rRNA sequence of the Chinese parasite was found to be most closely related to Theileria buffeli and clearly divergent to T. lestoquardi, suggesting that it was a yet unrecognized Theileria species. The phylogenetic relationship of Theileria species infecting sheep and goats on the basis of their 18S rRNA gene structure was addressed. We report on the existence of at least two additional ovine and caprine piroplasm species, designated T. luwenshuni and T. uilenbergi.
中国西北部曾有报道称，绵羊和山羊的一种致命疾病是由吕氏泰勒虫（Theileria lestoquardi）引起的。然而，病原体的一些特征与该寄生虫的属性并不相符。因此，我们测定了吕氏泰勒虫以及在中国发现的该寄生虫的18S核糖体RNA（18S rRNA）基因的核苷酸序列，并将其与其他泰勒虫属和巴贝斯虫属物种进行了比较。在推断的系统发育树中，中国寄生虫的18S rRNA序列位于由泰勒虫属物种组成的进化枝内，证明它属于该属。发现中国寄生虫的18S rRNA序列与水牛泰勒虫（Theileria buffeli）关系最为密切，与吕氏泰勒虫明显不同，这表明它是一种尚未被认识的泰勒虫属物种。基于18S rRNA基因结构，探讨了感染绵羊和山羊的泰勒虫属物种之间的系统发育关系。我们报告了至少另外两种感染绵羊和山羊的梨形虫物种的存在，分别命名为吕氏泰勒虫（T. luwenshuni）和乌氏泰勒虫（T. uilenbergi）。
