Impacts of climate change on the epidemiology of nematodes in arctic and subarctic ungulates

快速的气候变化正在彻底地、甚至可能是不可逆转地改变着北极的生态系统。传染病，特别是寄生虫病，加上气候变暖，可能在北美北极地区最近北美驯鹿数量的广泛减少中发挥了重要作用。气候变化可能通过以下方式增加北极有蹄类动物寄生虫病的影响：(1)改变现有寄生虫的传播模式；(2)在naïve种群中引入新的寄生虫种。本研究将探讨北美驯鹿一种重要的胃线虫——格鲁氏线虫对气候变化的响应。这种寄生虫可以降低驯鹿的身体状况和怀孕率，并影响驯鹿的数量。我们将研究O. gruehneri在冻土带上的生长和发育速度，并确定温度和/或湿度的变化如何影响寄生虫。对圈养驯鹿的同伴研究将确定感染的幼虫被驯鹿吞食后的命运。他们是立即成熟还是进入停滞发展阶段？这些数据将为了解和模拟不同气候变暖情景下O. gruehneri在北美驯鹿中的传播和影响提供重要信息。这项研究还将确定可能通过鹿和麋鹿种群向北扩张而引入北美驯鹿种群的胃肠道线虫，并将调查北美驯鹿对这些寄生虫的易感性。研究结果将为气候变化对北美驯鹿现有寄生虫群落的潜在影响以及新寄生虫物种向北扩展的风险提供新的信息。这项研究将为在快速变化的气候下管理和保护北美驯鹿提供重要信息。这些原则将适用于Rangifer的所有亚种以及全球其他宿主-寄生虫系统。

Rapid climate change, is radically, and probably irreversibly, altering arctic ecosystems. Infectious disease, parasitic disease in particular, together with climate warming, may be playing an important role in recent and widespread caribou population declines across the North American Arctic. Climate change could increase the impact of parasitic disease in arctic ungulates by: (1) changing the transmission patterns of the existing parasites; and (2) introduction of new parasite species to naïve populations.This research will investigate the response to climate change of an important abomasal (stomach) nematode, Ostertagia gruehneri, in caribou. This parasite can reduce body condition and pregnancy rates in reindeer and impact the population. We will examine the growth and development rates of O. gruehneri on the tundra and determine how changes in temperature and/or humidity may impact the parasite. Companion studies on captive reindeer will determine the fate of infective larvae when they are ingested by caribou (ie. Do they mature immediately or enter arrested development). These data will provide important information for understanding and modeling the transmission and impacts of O. gruehneri in caribou under different climate warming scenarios.This research will also identify the gastrointestinal nematodes that may be introduced to caribou populations through the northward expansion of deer and elk populations and will investigate the susceptibility of caribou to these parasites.Results will provide new information on the potential impacts of climate change on existing parasite communities in caribou and the risks associated with northern range expansion of new parasite species. This research will provide critical information for management and conservation of caribou in a rapidly changing climate. Principles will be relevant to all subspecies of Rangifer and to other host-parasite systems globally.