Department of Molecular Biology and Biotechnology, University of Dar es Salaam, Dar es Salaam, United Republic of Tanzania.
Section of Ruminant Medicine, Department of Clinical Sciences, Swedish University of Agricultural Sciences, Uppsala, Sweden.
Vector Borne Zoonotic Dis. 2021 Mar;21(3):191-199. doi: 10.1089/vbz.2020.2706. Epub 2021 Jan 15.
There has recently been a substantial increase in the number of tick species and tick-borne infectious agents in Tanzania. Owing to their impact on human, livestock, and wild animal health, increased knowledge of ticks is needed. So far, no published data on the genetic relationship between hard tick () sequences collected from cattle are available in Tanzania. Ticks from cattle in the wards, which lie at the border of Mikumi National Park, were collected in the dry season, November to December 2019. Morphological identification of ticks was initially performed at the genus level. To identify ticks at the species level, molecular analysis based on the 16S rRNA gene was performed. Evolutionary relationships and genetic distances between ticks were determined using MaximumLikelihood and Kimura 2-parameter methods, respectively. Based on morphology, two genera ( and ) were identified in the 630 adult ticks collected from a total of 252 cattle. Six species (, , , , , and ) were confirmed by BLASTn and phylogenetic analyses. Considerable mean and pairwise genetic distances were observed for and genera. The presence of different phylogenetic clusters and considerable mean and pairwise genetic distances observed reflect possible biological diversity of hard ticks present in the study area. Considering the value of the cattle in the livelihoods and economies of people and the country, the outcomes of this study will be useful in planning integrated control strategies for ticks and tick-borne diseases in Tanzania.
坦桑尼亚的蜱种和蜱传传染病原体数量最近显著增加。由于蜱类对人类、牲畜和野生动物健康的影响,需要增加对蜱类的了解。迄今为止,坦桑尼亚还没有关于从牛身上采集的硬蜱序列的遗传关系的已发表数据。2019 年 11 月至 12 月,在位于米库米国家公园边界的病房收集了牛身上的蜱虫。最初在属级水平上进行蜱虫的形态鉴定。为了在种级水平上鉴定蜱虫,基于 16S rRNA 基因进行了分子分析。使用最大似然法和 Kimura 2-参数法分别确定蜱虫的进化关系和遗传距离。根据形态学,从总共 252 头牛中采集的 630 只成年蜱虫中鉴定出两个属(和)。通过 BLASTn 和系统发育分析确认了 6 个种(、、、、和)。和属的平均和成对遗传距离都很大。不同的系统发育簇的存在以及观察到的大量平均和成对遗传距离反映了研究区域中存在的硬蜱可能具有生物多样性。考虑到牛在人们和国家的生计和经济中的价值,本研究的结果将有助于规划坦桑尼亚的蜱和蜱传疾病的综合控制策略。