Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.
Norwegian Institute for Nature Research, Trondheim, Norway.
PLoS One. 2021 Nov 29;16(11):e0260037. doi: 10.1371/journal.pone.0260037. eCollection 2021.
In birds, incubation temperature has received increased attention as an important source of phenotypic variability in offspring. A lower than optimal incubation temperature may negatively affect aspects of nestling physiology, such as body growth and energy metabolism. However, the long-term effects of sub-optimal incubation temperature on morphology and physiology are not well understood. In a previous study, we showed that zebra finches from eggs incubated at a low temperature (35.9°C) for 2/3 of the total incubation time suffered a lower post-fledging survival compared to individuals that had been incubated at higher temperatures (37.0 and 37.9°C). In the present study, we investigated whether these variations in incubation temperature could cause permanent long-lasting differences in body mass, body size, or basal metabolic rate. Furthermore, we tested whether the observed differences in survival between treatment groups would be reflected in the rate of physiological deterioration, assessed through oxidative damage and decreased metabolic rate with age (i.e. 'metabolic aging'). Incubation temperature did not significantly affect embryonic or nestling body growth and did not influence final adult body mass or body size. Nor was there any long-term effect on basal metabolic rate. Birds from eggs incubated at the lowest temperature experienced an accumulation of oxidative damage with age, although this was not accompanied by an accelerated rate of metabolic aging. The present results suggest that the low survival in these birds was possibly mediated by increased oxidative stress, but independent of body growth and the basal metabolic rate.
在鸟类中，孵化温度作为后代表型变异的一个重要来源受到了越来越多的关注。低于最佳孵化温度可能会对雏鸟的生理机能产生负面影响，例如身体生长和能量代谢。然而，亚最佳孵化温度对形态和生理机能的长期影响还不太清楚。在之前的一项研究中，我们发现，在孵化过程中，有 2/3的时间温度较低（35.9°C）的斑胸草雀雏鸟的出雏后存活率比在较高温度（37.0°C 和 37.9°C）下孵化的雏鸟要低。在本研究中，我们调查了这些不同的孵化温度是否会导致体重、体型或基础代谢率的永久性长期差异。此外，我们还测试了在存活率方面观察到的处理组差异是否会反映在生理恶化的速度上，这是通过氧化损伤和随年龄增长而降低的代谢率（即“代谢衰老”）来评估的。孵化温度并没有显著影响胚胎或雏鸟的身体生长，也没有影响最终的成年体重或体型。基础代谢率也没有长期影响。在最低温度下孵化的雏鸟随着年龄的增长会积累氧化损伤，尽管这并没有伴随着代谢衰老速度的加快。这些结果表明，这些鸟类的低存活率可能是由氧化应激增加介导的，但与身体生长和基础代谢率无关。
