Heritability, environmental effects, and genetic and phenotypic correlations of oxidative stress resistance-related enzyme activities during early life stages in Atlantic salmon

Oxidative stress (OS) may pose important physiological constraints on individuals, affecting trade-offs between growth and reproduction or ageing and survival. Despite such evolutionary and ecological importance, the results from studies on the magnitude of individual variation in OS resistance and the underlying causes of this variation such as genetic, environmental, and maternal origins, remain inconclusive. Using a high throughput methodology, we investigated the activity levels in three OS resistance-related enzymes (superoxide dismutase, SOD; glutathione reductase, GR; glutathione S-transferase, GST) during the early life stages of 1000 individuals from 50 paternal half-sib families in two populations of Atlantic salmon. Using animal mixed models, we detected the presence of narrow-sense heritability for SOD and GST; that for GST differed between populations due to differences in environmental variance. We found support for the presence of common environmental variation, including...