Physiological Limits to Hibernation in Large Mammals: Energetics, Body Composition, and Sleep in Black Bears (SGER)

OPP-00-76039 Barnes首席调查员将利用一个意想不到的机会，研究冬眠黑熊的冬眠行为、生理和神经生物学。阿拉斯加州渔猎部将提供两只刚刚进入冬眠的“麻烦”熊。这些熊将被摧毁，因为它们有危害人类的历史。首席调查员拥有室外人工洞穴，初步表明，大型哺乳动物冬眠动物实现节能的生理机制与小型冬眠动物，如北极地松鼠，Spennophilus parryii非常不同。例如，熊会大幅降低代谢率，并且不会禁食六个月。它们的体温只降低了3-5摄氏度(相比之下，地松鼠的体温降低了40摄氏度)，就实现了这一点。他们也几乎不间断地处于慢波睡眠状态。首席调查员将使用最先进的遥测技术测量这些变量，这使他们能够连续监测在自然条件下冬眠六个月的未被拴住的黑熊的体温、脑波、心电图和耗氧率。现在有了一个意想不到的机会，可以将这些测量扩展到可能怀孕的女性。这种冬眠生理学从未在会怀孕、分娩和哺育后代的冬眠熊身上进行过研究。首席研究员将与诺斯克极地研究所之前的Oivind Toien博士合作。托伊恩博士是这项研究的关键，因为他在呼吸测量和遥测方面拥有专业知识。

AbstractOPP-00-76039Barnes The Principal Investigator will take advantage of an unexpected opportunity for investigating hibernation behavior, physiology, and neurobiology in hibernating black bears, Ursus americanus. The Alaska Department of Fish and Game will provide two "trouble" bears that are just entering hibernation. These bears would be destroyed because they have a history of endangering people.The Principal Investigator has outdoor artificial dens and preliminary that suggests that large mammalian hibernators achieve energy savings with very different physiological mechanisms than do small hibernators, such as arctic ground squirrels, Spennophilus parryii. For example, bears substantially reduce their metabolic rate and do not fast for six months. They achieve this with only a 3-5oC reduction in body temperature (versus a 40 oC decline in ground squirrels). They also remain almost continuously in slow-wave sleep. The Principal Investigator will measure these variables using state-of-the-art telemetry, which allows them to continuously monitor body temperatures, brain waves, EKG, and rates of oxygen consumption in untethered black bears hibernating in natural conditions for six months. There is now an unexpected opportunity to extend these measurements to a female that is likely to be pregnant. This hibernation physiology has never been studied in a hibernating bear that will gestate, give birth, and nurse an offspring.The Principal Investigator will collaborate with Dr. Oivind Toien, previously with the Norsk Polar Institute. Dr. Toien is critical to the study because of his expertise in respirometry and telemetry.