Vitamins, stress and growth: the availability of antioxidants in early life influences the expression of cryptic genetic variation

Environmental inputs during early development can shape the expression of phenotypes, which has long-lasting consequences in physiology and life history of an organism. Here, we study whether experimentally manipulated availability of dietary antioxidants, vitamins C and E, influences the expression of genetic variance for antioxidant defence, endocrine signal and body mass in yellow-legged gull chicks using quantitative genetic models based on full siblings. Our experimental study in a natural population reveals that the expression of genetic variance in total antioxidant capacity in plasma increased in chicks supplemented with vitamins C and E despite the negligible effects on the average phenotype. This suggests that individuals differ in their ability to capture and transport dietary antioxidants or to respond to these extra resources, and importantly, this ability has a genetic basis. Corticosterone level in plasma and body mass were negatively correlated at the phenotypic level. S...个体发育早期的环境输入可塑造表型（phenotype）表达，进而对生物体的生理机能及生活史造成持久影响。本研究以黄腿鸥（yellow-legged gull）雏鸟为研究对象，采用基于全同胞（full siblings）家系的定量遗传模型（quantitative genetic models），探究实验调控膳食抗氧化剂——维生素C与维生素E的供给量，是否会影响抗氧化防御、内分泌信号与体质量相关性状的遗传方差表达。我们在自然种群中开展的实验研究显示，尽管对雏鸟的平均表型影响微乎其微，但补充维生素C与E的雏鸟，其血浆总抗氧化能力的遗传方差表达显著升高。这表明不同个体在摄取、转运膳食抗氧化剂，或是对额外补充的抗氧化资源产生响应的能力上存在差异；尤为重要的是，这种能力具有遗传基础。血浆皮质酮（corticosterone）水平与体质量在表型层面呈负相关。S...