Competition-mediated feedbacks in experimental multispecies epizootics.
Competition-mediated feedbacks in experimental multispecies epizootics.
复制标题
实验性多物种流行病中竞争介导的反馈。
作者：
T. Dallas;R. Hall;J. Drake
竞争结构的生态群落和改变宿主-病原体的相互作用。在环境传播的病原体中，抗感染竞争者可能通过竞争的负面影响（例如，通过降低宿主密度或引起增加感染易感性的营养应激）和/或降低传播效率的积极影响（例如，通过去除环境病原体阶段）。因此，非易感竞争者可能会增强、减少易感宿主密度和感染流行率，或对易感宿主密度和感染流行率没有净影响。在这里，我们将流行病学模型与实验流行病相结合，以测试与非易感竞争对手（Daphnia pulicaria）的资源竞争如何影响真菌微寄生虫（Metschnikowia bicuspidata）在易感宿主物种（D. dentifera）。我们的模型和实验表明，竞争对手的密度可以介导的方向和规模的竞争对感染动力学的影响，感染流行率的峰值发生在中间竞争对手的密度。在低密度下，非敏感竞争者D.蚤状菌可以通过进食从环境中去除真菌孢子来减少易感宿主的感染率。然而，当竞争者密度增加和资源变得有限时，D。通过增加易感宿主的进食率，从而增加真菌孢子的摄入，并且进一步通过减少易感宿主的种群大小，使其趋向于竞争性排斥，从而对易感宿主产生负面影响。总之，这些结果表明，竞争对手之间的权衡作为消费者的病原体，这有助于减少流行病的规模，作为修改器的易感主机觅食生态，影响感染率，可能会交替增强或抑制本地流行病的规模。
Competition structures ecological communities and alters host-pathogen interactions. In environmentally transmitted pathogens, an infection-resistant competitor may influence infection dynamics in a susceptible species through the negative impacts of competition (e.g., by reducing host density or causing nutritional stress that increases susceptibility to infection) and/or the positive impacts of reducing transmission efficiency (e.g., by removing environmental pathogen stages). Thus, a non-susceptible competitor may enhance, reduce, or have no net effect on susceptible host density and infection prevalence. Here, we couple an epidemiological model with experimental epidemics to test how resource competition with a non-susceptible competitor (Daphnia pulicaria) influences fungal microparasite (Metschnikowia bicuspidata) infection dynamics in a susceptible host species (D. dentifera). Our model and experiments suggest that competitor density can mediate the direction and magnitude of the effect of competition on infection dynamics, with a peak in infection prevalence occurring at intermediate competitor densities. At low densities, the non-susceptible competitor D. pulicaria may reduce infection prevalence in the susceptible host by removing fungal spores from the environment through feeding. However, when competitor density is increased and resources become limiting, D. pulicaria negatively impacts the susceptible host by increasing susceptible host feeding rates, and therefore fungal spore intake, and further by reducing susceptible host population size as it is driven toward competitive exclusion. In conclusion, these results show that a tradeoff between the competitor as a consumer of pathogen, which serves to reduce epidemic size, and as a modifier of susceptible host foraging ecology, which influences infection rates, may alternately enhance or dampen the magnitude of local epidemics.
个体发育饮食转变促进捕食者介导的共存
影响因子：
4.8
作者：
Wollrab;De Roos
通讯作者：
De Roos