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

这项研究将检测帝企鹅潜水中血液和肌肉氧气储备的耗竭与有氧潜水极限(ADL，潜水后血乳酸积累的开始)之间的关系。这一建议的智力价值包括对ADL概念的生理学基础的评估。ADL可能是最常用但很少测量的因子，用于解释和模拟潜水动物的行为和觅食生态。根据前人的研究和最近对帝企鹅潜水过程中呼吸和血液氧耗竭的研究，推测ADL是肌红蛋白(Mb)结合氧耗尽和初级运动肌肉糖酵解增加的结果。该项目将通过1)评估潜水期间肌肉耗氧的速率和程度与先前测量的ADL相关，2)描述帝企鹅血液中的血红蛋白-氧解离曲线，并将其与其他潜水和非潜水物种的血氧解离曲线进行比较，3)应用皇帝的血氧解离曲线对先前收集的氧和血红蛋白数据进行应用，以估计潜水过程中血液的氧耗速率和程度，以及4)测量肌肉磷酸肌酸和糖原浓度，以估计它们在潜水过程中对肌肉能量新陈代谢的潜在贡献。该项目还继续对罗斯海的皇帝殖民地进行普查和监测，鉴于渔业活动和B15-A冰山的移动，这一点尤为重要。该项目的更广泛影响包括：1)开发基于微处理器的“背包式”近红外分光光度计，不仅适用于其他物种，而且还适用于其他领域(即运动生理学)；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和南极实地考察方面的培训和论文研究；以及4)更好地理解ADL的概念及其在潜水行为和生理学领域的用途。此外，对罗斯海帝企鹅群体的年度普查，以及对以前开发的监测群体状况的远程摄像头的持续评估，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针对学童的教育推广计划。

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.