CANOSA Ivana SofÍa
congresos y reuniones científicas
In vivo effects of both methilfarnesoate and 17-hidroxyprogesterone on vitellin levels in ovary, hepatopancreas and hemolimph. A comparison between crayfish and crabs
FERRÉ, LILIAN; CANOSA, IVANA S.; SILVEYRA, GABRIELA R.; PAOLUCCI, MARINA; MEDESANI, DANIEL A.; RODRÍGUEZ, ENRIQUE M.
Simposio; Biennial Symposium of Freshwater Crayfish; 2014
International Association of Astacology
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 vitellogeninesis 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