Developmental changes in concentrations of vitellin, vitellogenin, and lipids in hemolymph, hepatopancreas, and ovaries from different ovarian stages of Indian white prawn Fenneropenaeus indicus

The objective of the present study was to characterize the relationship between vitellogenin (Vtg) and vitellin (Vt) concentration profiles during the reproductive cycle of the penaeid prawn Fenneropenaeus indicus. Vt was purified from ovaries of vitellogenic females by gradient ultracentrifugation. Purified Vt was used to raise polyclonal antibodies (anti-Vt) for this species. Vtg and Vt concentrations in hemolymph, hepatopancreas, and ovaries were measured by validated enzyme-linked immunosorbent assay (ELISA). Parallel displacement curves were obtained between purified Vt and tissues from ovaries, hepatopancreas, and hemolymph. Vtg concentrations increased in the hemolymph and hepatopancreas in the early stages of ovarian development (until GSI 3.4) and decreased significantly (P < 0.05) in the advanced maturation stages (GSI 3.4-7.1). In spite of the lower concentration of Vtg in hepatopancreas, accumulation of Vt in the ovaries was increasingly greater during oogenesis. These results indicate that the contribution of Vtg synthesized by the hepatopancreas is not sufficient for adequate development of oocytes in the female prawn F. indicus during vitellogenesis. (C) 2002 Elsevier Science B.V. All rights reserved.