Inter-Generational Costs of Oxidative Stress: Reduced Fitness in Daughters of Mothers That Experienced High Levels of Oxidative Damage during Reproduction

Abstract

Parental condition transfer effects occur when the parents’ physiological state during reproduction affects offspring performance. Oxidative damage may mediate such effects, yet evidence that oxidative damage experienced by parents during reproduction negatively affects offspring fitness is scarce and limited to early life stages. We show in Japanese quail (Coturnix japonica) that maternal levels of oxidative damage, measured during reproduction, negatively predict the number of offspring produced by daughters. This maternal effect on the daughter’s reproductive success was mediated by an effect on hatching success, rather than the number of eggs laid by daughters. We also observed a negative association between the father’s oxidative damage levels and the number of eggs laid by daughters, but a positive association between the father’s oxidative damage levels and the hatching success of these eggs. These opposing paternal effects cancelled each other out, resulting in no overall effect on the number of offspring produced by daughters. No significant association between a female’s own level of oxidative damage during reproduction and her reproductive success was observed. Our results suggest that oxidative damage experienced by parents are a better predictor of an individual’s reproductive performance than oxidative damage experienced by the individual itself. Although the mechanisms underlying these parental condition transfer effects are currently unknown, changes in egg composition or (epi-)genetic alterations of gametes may play a role. These findings highlight the importance of an inter-generational perspective when quantifying costs of physiological stress.