Diet and foraging-related aspects of host-parasite dynamics in freshwater systems

淡水系统中宿主-寄生虫动态的饮食和觅食相关方面

• 批准号: RGPIN-2020-04622
• 负责人: Koprivnikar, Janet
• 金额: $ 2.4万
• 依托单位: Ryerson University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=748538
• 关键词: Diet; foraging; related; aspects; host

Emerging and re-emerging infectious diseases caused by parasites and pathogens are of major concern for the health of humans, domestic animals, and wildlife in Canada and globally. It is thus vital to understand how hosts can resist and tolerate parasitic infections. Diet may influence resistance or tolerance, but even the risk of parasitism can affect foraging behaviour in animals, with consequences for individuals and populations. In this way, parasites could have significant influences in nature without ever infecting an organism, and sometimes this occurs in surprising ways. For instance, it has recently been shown that various aquatic animals readily consume the free-swimming infectious stages of helminth parasites. In other words, parasites do not just potentially affect host diets, but can be a part of some diets. Building upon our previous work with freshwater organisms and their helminth parasites as a model system, we will use a suite of interdisciplinary tools and approaches to study diet-based interactions of hosts and parasites through three specific related themes as part of a long-term program in aquatic disease ecology. Given current and projected world-wide environmental changes that will alter aquatic habitats, including food availability and parasite abundance, this may have consequences for host diets and parasite consumption which merit consideration in order to better predict and manage infectious disease outcomes. 1) Importance of host diet for resistance and tolerance to parasite infection Focusing on dietary antioxidants and essential lipids available to animals in aquatic habitats by eating algae and plants, we will examine how these affect host-parasite dynamics. This has important implications for understanding the ability of animals to defend themselves if particular dietary compounds are available, but also for parasite transmission. 2) Consumption of parasite infectious stages If free-living infectious stages are consumed, this can reduce transmission to other hosts. Identifying key consumers and the range of infectious stages they will eat, along with quantifying such removal, is therefore essential for understanding the potential scope for reduced transmission in this way. If such consumption is common, and parasites contribute substantially to the diets of some aquatic animals, it is also important to determine how they meet consumer energetic and nutritional needs. 3) Alterations in foraging behaviour under the risk of parasitism Finding food is a critical activity that takes up a lot of time and energy for most animals. If the risk of becoming infected causes animals to change their foraging behaviour in sub-optimal ways, this could have significant consequences for their ability to meet their needs. We will examine the extent to which aquatic animals alter their foraging based on specific risk.

由寄生虫和病原体引起的新兴和重新出现的传染病主要关注加拿大和全球人类，家畜和野生动植物的健康。因此，了解宿主如何抵抗和耐受寄生虫感染至关重要。饮食可能会影响抵抗力或容忍度，但即使是寄生虫的风险也会影响动物的觅食行为，对个人和人群的影响。这样，寄生虫就可以在自然界中产生重大影响而不会感染生物体，有时会以令人惊讶的方式发生。例如，最近已经显示，各种水生动物很容易消耗蠕虫寄生虫的自由速度传染阶段。换句话说，寄生虫不仅可能影响宿主饮食，而且可以成为某些饮食的一部分。在我们以前与淡水生物体及其蠕虫寄生虫作为模型系统的工作的基础上，我们将使用一系列跨学科工具和方法通过三个特定的相关主题来研究基于饮食的寄主和寄生虫的相互作用，这是水生疾病生态学长期计划的一部分。鉴于当前和预计的全球环境变化将改变水生栖息地，包括食物的可利用性和寄生虫丰度，这可能会对宿主饮食和寄生虫消费产生后果，这可能会考虑值得考虑的考虑因素，以便更好地预测和管理感染性疾病结果。 1）宿主饮食对寄生虫感染的抵抗力和耐受性的重要性，这些寄生虫感染着针对饮食抗氧化剂和水生栖息地中的动物可用的必需脂质，我们将研究它们如何影响宿主 - 寄生虫动力学。这对于理解动物捍卫自己的能力具有重要意义，如果有特定的饮食化合物，也对寄生虫传播也具有重要意义。 2）消费寄生虫感染阶段，如果消费自由活动的传染阶段，则可以减少向其他宿主的传播。因此，确定关键的消费者以及他们将要食用的传染性阶段以及量化这种删除的范围对于理解以这种方式减少传输的潜在范围至关重要。如果这种消费很常见，并且寄生虫对某些水生动物的饮食产生了重大贡献，那么确定它们如何满足消费者的能量和营养需求也很重要。 3）在寄生虫发现食物的风险下觅食行为的改变是一项关键活动，对于大多数动物而言，占用大量时间和能量。如果被感染的风险导致动物以次优的方式改变其觅食行为，那么这可能会对他们满足其需求的能力产生重大影响。我们将根据特定风险研究水生动物改变其觅食程度的程度。