Presence of vertebrate hormones estradiol and progesterone in female mud crabs during reproduction

Levels of estradiol 17beta (E2) and progesterone (PG) increased steeply in the red mud crab, Scylla serrata, at the onset of vitellogenesis.

• E2 and PG levels were analyzed in the ovary, hepatopancreas, and hemolymph across different vitellogenic stages.
• Maximum concentrations of E2 were found in the hepatopancreas, while PG peaked in the ovary, indicating different roles for these hormones.
• Hormone levels fluctuated in various embryonic stages of Emerita asiatica and S. serrata, suggesting a potential role as morphogenetic hormones.
• The presence of E2 and PG on lipovitellin from the ovary and eggs, as well as vitellogenin from hemolymph, indicates a function for these lipoproteins as steroid carriers.

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