HEMOLYMPH UNCONJUGATED AND CONJUGATED STEROIDS DURING REPRODUCTION INPENAEUS-JAPONICUS (CRUSTACEA, DECAPODA)

With reversed-phase high performance liquid chromatography (HPLC) with diode array detection, tile steroid and ecdysteroid contents have bee n studied of haemolymph of Penaeus japonicus during the reproductive c ycle. In females, conjugated androgens and conjugated and unconjugated estrogens are present, some occurring mainly in vitellogenic stages, others in immature or post-spawning animals. Tn males with quiescent t estes, during the winter months only unconjugated estrogens occur. Als o unconjugated cortisol is present in this period, in both males and f emales. The presence of a large amount of unknown steroids suggests th e existence in crustaceans of metabolic pathways different from those in vertebrates.