Metabolic fuel selection: Exercise and cold exposure

这项研究涉及动物在寒冷中生存和进行长距离迁徙的能力。第一个项目研究鱼类如何科普温度和环境污染物（如PCB）的变化。 冷血动物必须能够改变细胞膜，以确保在体温波动时维持正常的新陈代谢。由于许多多氯联苯在细胞膜内积累，因此了解这些毒素是否会干扰细胞膜在适应不同温度期间发生的救生变化尤为重要。 第二个项目研究候鸟如何在寒冷暴露和耐力运动期间管理它们的能量储备。 长距离迁徙的鸟类具有在非常寒冷的环境中生存的非凡能力，并在运动过程中使用脂肪储存。然而，这些惊人的运动员用来科普寒冷和不间断地旅行数千公里的机制尚未阐明。我们将确定加拿大鹅如何保护其身体的未隔热部分在冬季冻结。 我们将进行实验，以测试它们是否定期用温暖的血液淹没它们的腿，并在它们的脚中拥有抗冻蛋白以在寒冷中生存。 新孵化的鹅通常会在它们的母亲身上留下印记，但它们也可以在人类代理父母身上留下印记。 我们将把小鹅印在超轻型动力伞的飞行员身上，训练它们跟随它自由飞行。受过训练的成年鹅（4公斤）将配备一个150克的背包，其中包含一个能够监测其代谢燃料使用的自动化设备。 这是第一次，这个机器人将帮助我们测量他们如何在飞行过程中以创纪录的速度将能量从脂肪储备转移到工作肌肉。这项研究对以下方面具有重要意义：1）了解鱼类在环境污染物存在下如何科普全球变暖，2）制定新的野生动物保护政策，以帮助濒危候鸟管理能量，3）寻找新的方法来提高人类运动员的表现。

This research deals with the ability of animals to survive in the cold and to perform long-distance migrations. The first project investigates how fish cope with changes in temperature and environmental contaminants like PCBs. Cold-blooded animals must be able to modify cell membranes to ensure the maintenance of normal metabolism as their body temperature fluctuates. Because many PCBs accumulate within membranes, it is particularly important to know whether these toxins interfere with the life-saving changes in membranes taking place during acclimation to different temperatures. The second project investigates how migrant birds manage their energy reserves during cold exposure and endurance exercise. Long-distance migrant birds have a remarkable ability to survive in very cold environments and to use fat stores during locomotion. However, the mechanisms used by these amazing athletes to cope with cold and to travel non-stop for thousands of kilometers have not been elucidated. We will determine how Canada geese protect uninsulated parts of their body from freezing in the winter. We will carry out experiments to test whether they flood their legs with warm blood at regular intervals and possess antifreeze proteins in their feet to survive in the cold. Newly hatched geese normally imprint on their mother, but they can also do so on a human surrogate parent. We will imprint young geese on the pilot of an ultralight paramotor and train them to follow it in free flight. Trained adult geese (4 kg) will be fitted with a 150-g backpack containing an automated device able to monitor their use of metabolic fuels. For the first time, this robot will help us to measure how they transfer energy from fat reserves to working muscles at record rates during flight. This research has significant implications for: 1) understanding how fish will cope with global warming in the presence of environmental contaminants, 2) formulating new policies for wildlife conservation to help endangered migrant bird species to manage energy, and 3) finding new ways to improve the performance of human athletes.