PDF(Pubmed)
Abstract：
Batrachochytrium dendrobatidis (Bd) is a pathogenic chytrid fungus that is particularly lethal for amphibians. Bd can extirpate amphibian populations within a few weeks and remain in water in the absence of amphibian hosts. Most efforts to determine Bd presence and quantity in the field have focused on sampling hosts, but these data do not give us a direct reflection of the amount of Bd in the water, which are useful for parameterizing disease models, and are not effective when hosts are absent or difficult to sample. Current methods for screening Bd presence and quantity in water are time, resource, and money intensive. Here, we developed a streamlined method for detecting Bd in water with low turbidity (e.g., water samples from laboratory experiments and relatively clear pond water from a natural lentic system). We centrifuged water samples with known amounts of Bd to form a pellet and extracted the DNA from that pellet. This method was highly effective and the resulting concentrations across all tested treatments presented a highly linear relationship with the expected values. While the experimentally derived values were lower than the inoculation doses, the values were highly correlated and a conversion factor allows us to extrapolate the actual Bd concentration. This centrifuge-based method is effective, repeatable, and would greatly expand the domain of tractable questions to be explored in the field of Bd ecology. Importantly, this method increases equity in the field, because it is time- and cost-efficient and requires few resources.
摘要：
Batrachochytriumdendrobatidis（Bd）是一种致病性乳糜菌，对两栖动物特别致命。Bd可以在几周内消灭两栖动物种群，并在没有两栖动物宿主的情况下留在水中。确定现场Bd存在和数量的大多数努力都集中在采样宿主上，但是这些数据并不能直接反映水中的Bd含量，这对参数化疾病模型很有用，并且当宿主不存在或难以取样时无效。目前筛选水中Bd存在和数量的方法是时间，资源，和金钱密集型。这里,我们开发了一种检测低浊度水中Bd的流线型方法(例如，来自实验室实验的水样和来自天然真实系统的相对清澈的池塘水）。我们用已知量的Bd离心水样以形成沉淀,并从该沉淀提取DNA。该方法是高度有效的,并且在所有测试处理中得到的浓度呈现与预期值的高度线性关系。虽然实验得出的值低于接种剂量，这些值高度相关,转换因子允许我们推断实际的Bd浓度.这种基于离心机的方法是有效的，可重复,并将极大地扩展Bd生态学领域有待探索的易处理问题的领域。重要的是,这种方法增加了该领域的权益，因为它具有时间和成本效益，需要的资源很少。
