How now brown chow? Investigating direct functional roles for dissolved organic matter in aquatic animal nutrition and health

现在棕色松狮怎么样了？

• 批准号: RGPIN-2018-04134
• 负责人: Glover, Chris
• 金额: $ 2.4万
• 依托单位: Athabasca 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=764760
• 关键词: How; now; brown; chow; Investigating

Dissolved organic matter (DOM) represents the product of decomposing plant and soil matter that washes into water bodies and mixes with organic material generated by aquatic organisms themselves. At high concentrations, such as in waters draining forested regions, DOM is responsible for a tea-like, brown colouration. While generally considered to be biologically inert, recent findings suggest that DOM could have direct effects on aquatic animals. The current program seeks to develop an advanced understanding of these biological roles of DOM, through research in three distinct, but overlapping, areas. One research focus is to determine whether amino acids, a simple form of DOM, contribute to the growth of early life-stages of fish. Before larval fish develop a gastrointestinal tract that allows for the absorption of nutrients, there is evidence suggesting that amino acids are taken up by the skin and support the health of larval fish, but this has yet to be experimentally shown. This hypothesis will be tested in the current proposal, and if proven to be true, will offer a way of increasing the productivity and survival of fish in aquaculture, and could result in cheaper and more effective fish feeds. This research will also contribute to an enhanced fundamental understanding of fish nutrition, by examining the development of digestive and absorptive processes in the fish gut.A second research focus asks a similar question regarding the nutritive role of DOM in aquatic invertebrates, such as insect larvae. It is known that DOM-rich waters support larger populations of insect larvae, such as those of black flies and mosquitoes, than DOM-poor waters. There is some evidence to suggest that this is because these larvae, and other freshwater invertebrates such as the water flea, can use DOM to aid growth and survival. Knowledge of DOM roles in supporting insect nutrition will offer significant insight into factors that influence seasonal variation in biting insects, important vectors of disease and irritation. It may also facilitate prediction of how insect numbers will be impacted by factors that change aquatic DOM concentration and composition (e.g. forest fires, land-use changes), which may in turn have implications for human health and disease.The final research focus seeks to understand how the differing chemical composition of different DOMs affect their capacity to directly alter the biology of aquatic animals. This work builds on growing recognition that DOM can directly cause stress in animals. However, why certain pathways are affected, and why these effects are restricted to certain DOMs, is not well understood. Given that most studies ignore the possible roles of DOM on aquatic animal health, this research will increase awareness of DOM actions on biota, and will represent the first steps towards a model that will allow prediction of these effects based on site-specific DOM composition.

溶解的有机物（DOM）代表分解植物和土壤物质的产物，这些物质和土壤物质与水生生物本身产生的有机材料混合在一起。在高浓度的情况下，例如在排水森林地区的水域中，DOM负责类似茶的棕色颜色。尽管通常认为是生物学上的惰性，但最近的发现表明DOM可能会对水生动物产生直接影响。当前的计划试图通过在三个不同但重叠的领域进行研究，以对DOM的这些生物学作用有深入的了解。一种研究重点是确定氨基酸（一种简单的DOM形式）是否有助于鱼类生命的早期生长。在幼虫鱼产生胃肠道以吸收养分之前，有证据表明氨基酸被皮肤吸收并支持幼虫鱼的健康，但这尚未实验表明。该假设将在当前的提案中进行检验，如果被证明是正确的，将提供一种提高水产养殖中鱼类生产力和生存的方法，并可能导致更便宜，更有效的鱼类饲料。这项研究还将通过研究鱼类肠道中的消化和吸收过程的发展，从而有助于增强对鱼类营养的基本了解。第二次研究重点提出了一个类似的问题，该问题涉及DOM在水生无脊椎动物中的营养作用，例如昆虫幼虫。众所周知，与dom-poor的水相比，富含Dom的水域支持昆虫幼虫的群体，例如黑蝇和蚊子的种群。有证据表明，这是因为这些幼虫和其他淡水无脊椎动物（例如水跳蚤）可以使用DOM来帮助生长和生存。了解DOM在支持昆虫营养中的作用的知识将对影响刺眼昆虫的季节性变化，疾病和刺激的重要媒介的因素有很大的见解。它还可能促进预测昆虫数量如何受到改变水生dom浓度和成分的因素（例如森林火灾，土地利用变化），这可能对人类健康和疾病产生影响。最终的研究重点旨在了解不同DOM的不同化学成分如何影响其直接改变水上动物生物学的能力。这项工作以日益认识到DOM可以直接引起动物压力的认识为基础。但是，为什么某些途径受到影响，以及为什么这些效果仅限于某些DOM的原因尚未得到很好的理解。鉴于大多数研究都忽略了DOM在水生动物健康中的可能作用，因此这项研究将提高人们对生物群体作用的认识，并且将代表迈向模型的第一步，该模型将允许基于特定地点的DOM组成来预测这些效果。