In vivo effects of methyl farnesoate and 17-hydroxyprogesterone on vitellin level in the ovary and hepatopancreas and vitellogenin level in the hemolymph of crayfish and crabs.

FERRÉ, LILIAN; CANOSA, IVANA; SILVEYRA, GABRIELA; PAOLUCCI, MARINA; MEDESANI, DANIEL; RODRÍGUEZ, ENRIQUE

Sapporo, Hokkaido

Simposio; International Association of Astacology - Biennial Symposium; 2014

International Association of Astacology / Carcinological Society of Japan

Background. In crustaceans, female reproduction is regulated by a variety of hormonal and neuronal factors which include, among others, methyl farnesoate, a stimulator of vitellogenesis and 17-hydroxyprogesterone. Vitellogenin is synthesized in several tissues including the ovary itself and the hepatopancreas, from which vitellogenin is released in the hemolymph and taken up by the ovary where it is stored as vitellin. To investigate the role of methyl farnesoate and 17-hydroxyprogesterone on vitellogenesis in crustaceans, we in vivo administered both hormones to two crustacean species. Animals and Methods. Adult females of the crayfish Cherax quadricarinatus and the crab Neohelice granulata were fed twice a week on a diet (33% of protein) enriched with methyl farnesoate (MF) or 17-hydroxyprogesterone (PROG) at a dose of 2 nmol/g for 30 days, during the post-reproductive period (May-June). Animals were kept under controlled conditions of both temperature and photoperiod. At the end of the experimental period, total body, ovary and hepatopancreas weights, were determined in order to calculate, respectively, the gonadosomatic (GSI) and hepatosomatic (HSI) indexes. Besides, vitellin level was determined in the ovary and hepatopancreas and vitellogenin level in the hemolymph by ELISA assay. Results. A significant (p>0.05) increase of both GSI and vitellin level in the ovary was detected after MF treatment, in both species. PROG produced a significant (p