A comparative study of the morphology, molecular identity and bacterial communities of nymph and adult ticks in Sydney

We have collected 4 species of Australian endemic ticks, Ixodes holocyclus, Ixodes trichosuri, Ixodes tasmani, and Haemaphysalis bancrofti, from around Sydney. Nymph ticks were collected by flagging / dragging the environment, while adult ticks were collected from dogs in veterinary clinics. While only I. holocyclus was recovered from dogs in veterinary clinics, I. holocyclus, I. trichosuri, I. tasmani and H. bancrofti were found in the surrounding environment. DNA was isolated using a commercial DNA isolation kit (Bioline Genomic DNA Kit) from nymph ticks, adults ticks and two DNA extraction controls were included as 'BLANK' reactions. It was then sequenced at the V3-V4 hypervariable 16S rRNA gene region. The aim was to determine whether environmental factors could have an influence on the tick's microbiome, and lastly, whether Borrelia spp. was present in Sydney ticks.

本研究于悉尼周边采集到4种澳大利亚特有蜱类（tick）：全环硬蜱（Ixodes holocyclus）、毛鼠硬蜱（Ixodes trichosuri）、塔斯马尼亚硬蜱（Ixodes tasmani）以及班氏血蜱（Haemaphysalis bancrofti）。蜱若虫通过环境布旗拖拽法采集，而成蜱则采自兽医诊所就诊犬只的体表。尽管兽医诊所的犬只仅分离到全环硬蜱，但周边环境中同时检出全环硬蜱、毛鼠硬蜱、塔斯马尼亚硬蜱及班氏血蜱。我们采用商用DNA提取试剂盒（Bioline Genomic DNA Kit）从蜱若虫和成蜱样本中提取基因组DNA，并设置两份"BLANK"对照反应。随后对16S rRNA基因的V3-V4高变区进行测序。本研究旨在探究环境因素是否会对蜱类微生物组产生影响，同时检测悉尼地区蜱类是否存在疏螺旋体属（Borrelia spp.）病原体。