The results show that, during standard conditions of embryonic incubation, vitamin C levels decrease from 70 to 15 mu g/egg throughout the development, whereas vitamin E content remains stable. Under hypo-osmotic stress, the vitamin C content of eggs with embryonic development is reduced from a control value of 5.7 mu g/egg to 3.8 mu g/egg, and vitamin E seems unaffected by this stress condition. Paralarvae of E. megalocyathus fed with vitamin C-enriched Anemia did not show significant differences in survival, growth or vitamin E content. But they displayed a higher vitamin C content at 21 DAH (days after hatching). On the other hand, vitamin E levels did vary throughout paralarvae development, peaking at 21 DAH. We discuss the potential relationship between these vitamins uses and the reproductive processes as well as dietary implications for breeders under conditioning or for paralarvae rearing.