Näslund Joacim, Pauliny Angela, Blomqvist Donald, Johnsson Jörgen I
Department of Biological and Environmental Sciences, University of Gothenburg, Gothenburg, Sweden,
Oecologia. 2015 Apr;177(4):1221-30. doi: 10.1007/s00442-015-3263-0. Epub 2015 Feb 20.
After a period of food deprivation, animals often respond with a period of faster than normal growth. Such responses have been suggested to result in decreased chromosomal maintenance, which in turn may affect the future fitness of an individual. Here, we present a field experiment in which a food deprivation period of 24 days was enforced on fish from a natural population of juvenile brown trout (Salmo trutta) at the start of the high-growth season in spring. The growth of the food-deprived fish and a non-deprived control group was then monitored in the wild during 1 year. Fin tissue samples were taken at the start of the experiment and 1 year after food deprivation to monitor the telomere dynamics, using reduced telomere length as an indicator of maintenance cost. The food-deprived fish showed partial compensatory growth in both mass and length relative to the control group. However, we found no treatment effects on telomere dynamics, suggesting that growth-compensating brown trout juveniles are able to maintain their telomeres during their second year in the stream. However, body size at the start of the experiment, reflecting growth rate during their first year of life, was negatively correlated with change in telomere length over the following year. This result raises the possibility that rapid growth early in life induces delayed costs in cellular maintenance.
经过一段时间的食物剥夺后，动物通常会出现一段比正常生长速度更快的时期。有人认为这种反应会导致染色体维持能力下降，进而可能影响个体未来的健康状况。在此，我们展示了一项野外实验，在春季高生长季节开始时，对来自幼年褐鳟（Salmo trutta）自然种群的鱼实施了为期24天的食物剥夺期。然后在野外对食物剥夺组鱼和非剥夺对照组鱼的生长情况进行了为期1年的监测。在实验开始时以及食物剥夺1年后采集鳍组织样本，以监测端粒动态，使用缩短的端粒长度作为维持成本的指标。相对于对照组，食物剥夺组的鱼在体重和体长方面都表现出部分补偿性生长。然而，我们没有发现处理对端粒动态有影响，这表明具有生长补偿能力的幼年褐鳟能够在溪流中的第二年维持其端粒。然而，实验开始时的体型，反映了它们出生后第一年的生长速度，与接下来一年中端粒长度的变化呈负相关。这一结果增加了生命早期快速生长会导致细胞维持方面延迟成本的可能性。
