Havenstein Nadine, Langer Franz, Fietz Joanna
Institute of Animal Husbandry and Animal Breeding, University of Hohenheim, Stuttgart, Germany.
Institute of Zoology, University of Hohenheim, Stuttgart, Germany.
J Comp Physiol B. 2018 Mar;188(2):359-371. doi: 10.1007/s00360-017-1111-8. Epub 2017 Jul 29.
The oxygen delivery system is one major determinant of the performance of vertebrates and responds sensitively to a variety of internal and environmental factors. To understand physiological mechanisms underlying variations of fitness, we investigated effects of demanding conditions associated with certain life-history events, food availability, and population density on the oxygen delivery system in free-ranging edible dormice (Glis glis). We sampled blood (n = 248) and urine (n = 319), performed an erythrocyte haemogram and visually determined the presence of haemoglobinuria. Reproduction leads to increased mortality in edible dormice and our study now reveals severe haematological impairments during reproduction that were associated with nutrient and energy deficits and stress. These effects were even more pronounced in subsequent reproductive years, indicating prolonged physiological impairment. Under limited food availability, the rate of erythrocyte generation was reduced. This seems to be part of an energy saving strategy instead of representing a poor body condition as survival probability in this species is high in years of low food availability. A high prevalence ratio of haemoglobinuria (up to 85%) at the end of the active season indicated amplified erythrocyte destruction through haemolysis. This may be the result of a preparative mechanism to avoid massive oxidative damage during the long hibernation period. Most ecophysiological studies so far focus on single erythrocyte parameters on a short time scale, which could be misleading. Our results clearly highlight that a wide-array RBC approach is a powerful tool for investigating mechanisms underlying physiological performance and fitness, also for other vertebrate taxa.
氧气输送系统是脊椎动物生理机能的一个主要决定因素，并且对多种内部和环境因素都有敏感反应。为了了解与健康状况变化相关的生理机制，我们研究了与某些生活史事件、食物可利用性和种群密度相关的苛刻条件对自由放养的食用睡鼠（Glis glis）氧气输送系统的影响。我们采集了血液（n = 248）和尿液（n = 319），进行了红细胞血常规检查，并通过肉眼判断血红蛋白尿的存在。繁殖会导致食用睡鼠死亡率增加，我们的研究现在揭示了繁殖期间严重的血液学损伤，这些损伤与营养和能量缺乏以及压力有关。这些影响在随后的繁殖年份中更为明显，表明生理损伤持续时间延长。在食物可利用性有限的情况下，红细胞生成率降低。这似乎是一种节能策略的一部分，而不是代表身体状况不佳，因为在食物可利用性低的年份，该物种的生存概率很高。活跃季节结束时血红蛋白尿的高患病率（高达85%）表明红细胞通过溶血被大量破坏。这可能是一种准备机制的结果，以避免在漫长的冬眠期内发生大量氧化损伤。迄今为止，大多数生态生理学研究在短时间尺度上关注单个红细胞参数，这可能会产生误导。我们的结果清楚地表明，广泛的红细胞方法是研究生理机能和健康状况潜在机制的有力工具，对其他脊椎动物类群也是如此。
