Ramón-Laca Ana, Gleeson Dianne, Yockney Ivor, Perry Michael, Nugent Graham, Forsyth David M
EcoGene®, Landcare Research, Auckland, New Zealand.
Institute for Applied Ecology, University of Canberra, Canberra, Australia.
PLoS One. 2014 Mar 17;9(3):e92043. doi: 10.1371/journal.pone.0092043. eCollection 2014.
Identifying species occupying an area is essential for many ecological and conservation studies. Faecal DNA is a potentially powerful method for identifying cryptic mammalian species. In New Zealand, 10 species of ungulate (Order: Artiodactyla) have established wild populations and are managed as pests because of their impacts on native ecosystems. However, identifying the ungulate species present within a management area based on pellet morphology is unreliable. We present a method that enables reliable identification of 10 ungulate species (red deer, sika deer, rusa deer, fallow deer, sambar deer, white-tailed deer, Himalayan tahr, Alpine chamois, feral sheep, and feral goat) from swabs of faecal pellets. A high resolution melting (HRM) assay, targeting a fragment of the 12S rRNA gene, was developed. Species-specific primers were designed and combined in a multiplex PCR resulting in fragments of different length and therefore different melting behaviour for each species. The method was developed using tissue from each of the 10 species, and was validated in blind trials. Our protocol enabled species to be determined for 94% of faecal pellet swabs collected during routine monitoring by the New Zealand Department of Conservation. Our HRM method enables high-throughput and cost-effective species identification from low DNA template samples, and could readily be adapted to discriminate other mammalian species from faecal DNA.
识别占据某一区域的物种对于许多生态和保护研究至关重要。粪便DNA是识别隐秘哺乳动物物种的一种潜在有力方法。在新西兰,有10种有蹄类动物(偶蹄目)已建立野生种群,并因其对本土生态系统的影响而被当作有害生物进行管理。然而,基于粪便颗粒形态来识别管理区域内存在的有蹄类物种并不可靠。我们提出了一种方法,能够从粪便颗粒拭子中可靠地识别出10种有蹄类物种(马鹿、梅花鹿、水鹿、黇鹿、黑鹿、白尾鹿、喜马拉雅塔尔羊、高山羚羊、野羊和野山羊)。我们开发了一种针对12S rRNA基因片段的高分辨率熔解(HRM)分析方法。设计了物种特异性引物,并将其组合在多重PCR中,从而产生不同长度的片段,因此每个物种具有不同的熔解行为。该方法利用这10个物种各自的组织进行开发,并在盲法试验中得到验证。我们的方案能够对新西兰保护部在常规监测期间收集的94%的粪便颗粒拭子确定物种。我们的HRM方法能够从低DNA模板样本中进行高通量且经济高效的物种识别,并且可以很容易地进行调整,以从粪便DNA中鉴别出其他哺乳动物物种。