Effects of Foraging on the Lipid Biochemistry of Freely Diving Weddell Seals

觅食对自由潜水威德尔海豹脂质生物化学的影响

• 批准号: 0130417
• 负责人: Michael Castellini
• 金额: $ 62.98万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-06-01 至 2006-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0130417&HistoricalAwards=false
• 关键词: Effects; Foraging; Lipid; Biochemistry; Freely

The primary goal of this program is to quantify the dynamics of lipid uptake and utilization in a naturally foraging mammalian carnivore by examining freely diving Weddell seals in Antarctica. This species offers a unique opportunity to follow the biochemistry and physiology of nutrient utilization in a large carnivore that may not be possible in any other system. This is due to the essentially impossible logistics of working with large predators such as free-ranging felids (e.g, lions, tigers) or ursids (bears) and obtaining multiple blood samples and measuring digestive chemistry while the animal is actively foraging. While such studies can be conducted in laboratory or zoo settings, they are necessarily limited to using captive animals where feeding times are typically constrained by husbandry requirements and to human-determined diets. However, a unique opportunity to perform digestive chemistry experiments in actively foraging large carnivores in the wild exists in the Antarctic. For several decades, the Weddell seal has been the focus of studies on natural diving physiology because of the ability to work with the species using isolated holes in the sea ice near McMurdo Station, Antarctica. In that system, the seal has access to a single ice hole where it routinely returns to breathe, sleep, digest, etc. With the use of blood-sampling catheters, serial samples of blood can be collected whenever the seal returns to the surface between diving bouts. Seals rely primarily on lipid metabolism for their daily energy demands and in this new program, nutrient metabolism in predatory carnivores will be studied by examining the kinetics of lipid uptake and utilization during active foraging bouts. Labeled blood samples from freely diving animals will be used to quantify lipid turnover rates and to characterize the various components of the lipid pool. Adult seal lipid uptake and utilization will be compared to similar processes in pups, which are biochemically adapted for massive and rapid lipid utilization while nursing. This project will provide rare and perhaps unparalleled data on the foraging biochemistry of freely living carnivores. Results will also provide insight not only to Antarctic ecosystem studies, but to the entire field of lipid metabolism in mammals and to the study of carnivore biology.

该计划的主要目标是通过研究南极洲自由潜水的威德尔海豹来量化自然觅食的哺乳动物食肉动物的脂质摄取和利用的动态。这一物种提供了一个独特的机会，遵循在一个大型食肉动物，可能不可能在任何其他系统的营养利用的生物化学和生理学。这是由于基本上不可能的后勤工作与大型食肉动物，如自由放养的猫科动物（如狮子，老虎）或熊（熊），并获得多个血液样本和测量消化化学，而动物是积极觅食。虽然这些研究可以在实验室或动物园环境中进行，但它们必然限于使用饲养时间通常受饲养要求和人类确定饮食限制的圈养动物。然而，在南极存在一个独特的机会，在积极觅食大型食肉动物在野外进行消化化学实验。几十年来，威德尔海豹一直是自然潜水生理学研究的焦点，因为它能够利用南极洲麦默多站附近海冰上的孤立洞穴与该物种合作。在该系统中，海豹可以进入一个单独的冰洞，在那里它通常会返回呼吸、睡眠、消化等。海豹主要依靠脂质代谢来满足日常能量需求，在这个新项目中，将通过检查活跃觅食期间脂质吸收和利用的动力学来研究捕食性食肉动物的营养代谢。自由潜水动物的标记血样将用于定量脂质周转率并表征脂质池的各种组分。成年海豹的脂质摄取和利用将与幼崽中的类似过程进行比较，幼崽在生物化学上适应于在哺乳时大量和快速的脂质利用。这个项目将提供关于自由生活的食肉动物觅食生物化学的罕见的，也许是无与伦比的数据。研究结果不仅将为南极生态系统研究，也将为哺乳动物脂质代谢的整个领域和食肉动物生物学的研究提供见解。