The Aerobic Dive Limit: Oxygen Transport and Depletion in Emperor Penguins

该研究将检查帝企鹅潜水时血液和肌肉氧储存消耗与记录的有氧潜水极限（ADL，潜水后血液乳酸积累的开始）的关系。这一建议的智力价值包括它对ADL概念的生理基础的评估。ADL可能是最常用的，但很少测量，解释和模拟潜水动物的行为和觅食生态的因素。基于先前的研究，以及最近对帝企鹅潜水时呼吸和血氧消耗的调查，我们假设ADL是由于肌红蛋白（Mb）结合氧的消耗和初级运动肌肉糖酶解的增加。该项目将通过以下方式准确定义ADL的生理机制：1)评估潜水期间肌肉耗氧的速率和幅度与先前测量的ADL的关系；2)表征帝企鹅血液中的血红蛋白-氧解离曲线，并将该曲线与其他潜水和非潜水物种的曲线进行比较。3)将皇帝血红蛋白-氧解离曲线应用于先前收集的氧气和血红蛋白数据，以估计潜水期间血氧消耗的速率和幅度；4)测量肌肉磷酸肌酸和糖原浓度，以估计它们对潜水期间肌肉能量代谢的潜在贡献。该项目还继续对罗斯海的帝企鹅种群进行普查和监测，鉴于渔业活动和冰山B15-A的移动，这一点尤为重要。项目的更广泛影响包括：1)基于微处理器的“背包式”近红外分光光度计的技术开发，不仅适用于其他物种，也适用于其他领域（如运动生理学）；2)与圣地亚哥美国海军医院麻醉科合作，对麻醉住院医师进行研究技术培训；3)对两名研究生进行这些技术培训和论文研究，并进行南极实地研究。4)更好地理解ADL概念及其在潜水行为和生理学领域的应用。此外，对罗斯海帝企鹅栖息地的年度普查，以及对先前开发的远程摄像机的持续评估，将构成一个新的教育网站的基础，并允许通过圣地亚哥海洋世界开发一个教育推广计划，向学童提供教育服务。

The research will examine blood and muscle oxygen store depletion in relation to the documented aerobic dive limit (ADL, onset of post-dive blood lactate accumulation) in diving of emperor penguins. The intellectual merits of this proposal involve its evaluation of the physiological basis of the ADL concept. The ADL is probably the most commonly-used, but rarely measured, factor to interpret and model the behavior and foraging ecology of diving animals. Based on prior studies, and on recent investigations of respiratory and blood oxygen depletion during dives of emperor penguins, it is hypothesized that the ADL is a result of the depletion of myoglobin (Mb)-bound oxygen and increased glycolysis in the primary locomotory muscles. This project will accurately define the physiological mechanisms underlying the ADL through 1) evaluation of the rate and magnitude of muscle oxygen depletion during dives in relation to the previously measured ADL, 2) characterization of the hemoglobin-oxygen dissociation curve in blood of emperor penguins and comparison of that curve to those of other diving and non-diving species, 3) application of the emperor hemoglogin-oxygen dissociation curve to previously collected oxygen and hemoglobin data in order to estimate the rate and magnitude of blood oxygen depletion during dives, and 4) measurement of muscle phosphoocreatine and glycogen concentrations in order to estimate their potential contributions to muscle energy metabolism during diving. The project also continues the census and monitoring of the emperor colonies in the Ross Sea, which is especially important in light of both fisheries activity and the movement of iceberg B15-A. Broader impacts of the project include: 1) technological development of microprocessor-based, "backpack" near-infrared spectrophotometer, which will be applicable not only to other species, but also to other fields (i.e., exercise physiology), 2) collaboration with the Department of Anesthesia at the U.S. Naval Hospital in San Diego in the training of anesthesia residents in research techniques, 3) the training and thesis research of two graduate students in these techniques and in Antarctic field research, and 4) a better understanding of the ADL concept and its use in the fields of diving behavior and physiology. In addition the annual census of emperor penguin colonies in the Ross Sea, in conjunction with the continued evaluation of previously developed remote cameras to monitor colony status, will form the basis of a new educational web site, and allow development of an educational outreach program to school children through SeaWorld of San Diego.