Eikenaar Cas, Hessler Sven, Hegemann Arne
Institute of Avian Research, An der Vogelwarte 21, Wilhelmshaven 26386, Germany.
Department of Biology, Lund University, Ecology Building, Lund 223 62, Sweden.
R Soc Open Sci. 2020 Feb 5;7(2):192031. doi: 10.1098/rsos.192031. eCollection 2020 Feb.
Migratory flight is physiologically highly demanding and has been shown to negatively affect multiple parameters of constitutive immune function (CIF), an animal's first line of physiological defence against infections. In between migratory flights, most birds make stopovers, periods during which they accumulate fuel for the next flight(s). Stopovers are also commonly thought of as periods of rest and recovery, but what this encompasses is largely undefined. Here, we show that during stopover, northern wheatears a long-distance migratory bird, can rapidly increase constitutive innate immune function. We caught and temporarily caged birds under ad libitum food conditions at a stopover site in autumn. Within 2 days, most birds significantly increased complement activity and their ability to kill microbes. Changes in immune function were not related to the birds' food intake or extent of fuel accumulation. Our study suggests that stopovers may not only be important to refuel but also to restore immune function. Additionally, the increase in CIF could help migrating birds to deal with novel pathogens they may encounter at stopover sites.
迁徙飞行对生理要求极高，并且已被证明会对组成性免疫功能（CIF）的多个参数产生负面影响，而组成性免疫功能是动物抵御感染的第一道生理防线。在迁徙飞行之间，大多数鸟类会中途停留，在此期间它们为下一次飞行积累能量。中途停留通常也被认为是休息和恢复的时期，但其中具体包含哪些内容在很大程度上并不明确。在这里，我们表明，在中途停留期间，一种长途候鸟白斑黑石鵖能够迅速增强组成性先天免疫功能。我们在秋季的一个中途停留地点，在食物充足的条件下捕获并临时圈养了这些鸟。在两天内，大多数鸟的补体活性和杀灭微生物的能力显著增强。免疫功能的变化与鸟类的食物摄入量或能量积累程度无关。我们的研究表明，中途停留可能不仅对补充能量很重要，而且对恢复免疫功能也很重要。此外，组成性免疫功能的增强可以帮助候鸟应对它们在中途停留地点可能遇到的新病原体。
