CHANGES IN OVARIAN UNCONJUGATED AND CONJUGATED STEROID TITERS DURING VITELLOGENESIS IN PENAEUS-MONODON

Gas chromatography/mass spectrometry with selected ion monitoring (GC/MS(SIM) has been employed to study the steroid composition of the ovary of Penaeus monodon at various stages during ovarian maturation. The titers of conjugated 17β-estradiol and estrone in both unconjugated and conjugated form were found to be maximal at stages II and III of the vitellogenic cycle, that is at the major vitellogenic stages. Conjugated pregnenolone and unconjugated and conjugated dehydroepiandrosterone (DHEA) were also found to be maximal at these stages. Unconjugated progesterone was found in ovary at the last two stages (stages III and IV) of maturation, and conjugated testosterone was detected in mature, stage IV ovary only. The significance of these observations with respect to ovarian maturation in P. monodon is discussed. © 1990.