The metabolism of astaxanthin during the embryonic development of the crayfish Astacus leptodactylus Eschscholtz (Crustacea, Astacidea).

The developing eggs of the crayfish Astacus leptodactylus are found to contain important carotenoid amounts. Free astaxanthin, mainly associated with protein and lutein represent the main pigments occurring in the yolk at the end of the embryonic period. Esterification processes affecting astaxanthin appear concomitantly with the resorption of vitellin reserves, the activation of the digestive gland and the rapid decrease of lutein amounts. Esterified astaxanthin contents increase significantly within the interval between the juvenile stages I and II. Nevertheless, free astaxanthin levels appear insufficient to balance the amounts of the esterified form, scored at the end of the endotrophic period.