Increased lipid peroxidation occurs during development in Japanese quail (Coturnix japonica) embryos

The growth of the avian embryo is paralleled by an exponential increase in the rate of whole-embryonic oxygen consumption, which potentially increases oxidative damage. Age-related patterns of tissue lipid peroxidation were characterised in brain, liver and heart tissue of developing Japanese quail (Coturnix japonica) embryos between 9 and 15 d of age, over which embryo mass increased by a factor of 6. Lipid peroxidation was quantified in each tissue by spectrophotometric measurement of malondialdehyde using the thiobarbituric acid reactive substances assay. In all tissues, lipid peroxidation increased greatly as development proceeded. Concentrations of malondialdehyde increased in parallel with the cumulative amount of oxygen consumed by the developing embryo consistent with the hypothesis that oxidative stress results from the production of free radicals due to oxidative metabolism. This study describes in vivo oxidative stress in developing avian embryos and suggests that rates of embryonic growth, oxidative metabolism and oxidative damage likely vary in parallel.