Antioxidants in eggs of great tits Emphasis Type=

Authors: Anders Pape Møller Filis Karadas Timothy A Mousseau

Publish Date: 2008/04/08

Volume: 178, Issue: 6, Pages: 735-743

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Abstract

Antioxidants are powerful protectors against the damaging effects of free radicals that constitute the inevitable byproducts of aerobic metabolism Growing embryos are particularly susceptible to the damaging effects of free radicals produced during rapid growth and mothers of many species provide protection against such damage by allocating antioxidants to their eggs Birds living in radioactively contaminated areas use dietary antioxidants to cope with the damaging effects of radiation but females also allocate dietary antioxidants to eggs potentially enforcing a physiological tradeoff between selfmaintenance and reproductive investment Here we tested whether female great tits Parus major breeding in radioactively contaminated study areas near Chernobyl allocated less dietary antioxidants to eggs and whether such reduced allocation of dietary antioxidants to eggs had fitness consequences Concentrations of total yolk carotenoids and vitamins A and E were depressed near Chernobyl compared to concentrations in a less contaminated Ukrainian study area and a French control study area and all antioxidants showed dosedependent relationships with all three dietary antioxidants decreasing with increasing level of radiation at nest boxes These effects held even when controlling statistically for potentially confounding habitat variables and covariation among antioxidants Laying date was advanced and clutch size increased at nest boxes with high dose rates Hatching success increased with increasing concentration of vitamin E implying that hatching success decreased at boxes with high levels of radiation eventually eliminating and even reversing the higher potential reproductive output associated with early reproduction and large clutch size These findings are consistent with the hypothesis that radioactive contamination reduced levels of dietary antioxidants in yolks with negative consequences for hatching success and reproductive successWe are grateful to S Gaschak G Milinevski A M Peklo E Pysanets I Chizhevsky O Bondarenko and M Bondarkov for logistic help during our visits to Ukraine C Biard kindly provided information on yolk composition from France We received funding from the CNRS France the University of South Carolina School of the Environment Bill Murray and the Samuel Freeman Charitable Trust the Civilian Research Development Foundation the National Science Foundation and the National Geographic Society to conduct this research

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