HISTOCHEMICAL AND BIOCHEMICAL-STUDY OF LIPIDS DURING THE REPRODUCTIVE-CYCLE OF THE TOADFISH, HALOBATRACHUS-DIDACTYLUS (SCHNEIDER, 1801)

Histochemical and biochemical aspects of the lipids of the female toad fish, Halobatrachus didactylus, during its annual reproductive cycle w ere studied. Oil droplets containing neutral lipids, and protein-yolk granules containing phospholipids and glycolipids were observed in the vitellogenic oocytes. The cytoplasm of the hepatocytes also contained neutral lipids (oil droplets). The highest lipid concentrations were observed in the liver and the lowest in the serum. In the liver, trigl ycerides predominated in the fractional composition of lipids. The ova rian and hepatic total lipids and phospholipids, and the hepatic trigl yceride levels were higher during the reproductive period (from Januar y to May). A positive relationship between the gonadosomatic index (GS I), hepatosomatic index (HSI) and ovarian total lipids, cholesterol, a nd phospholipids was found. The HSI was also positively correlated wit h the hepatic and serum lipids, whereas the GSI showed a negative rela tionship with the serum lipids. Results obtained show that the GSI and HSI variations observed, during the annual reproductive cycle of H. d idactylus females, are associated with histological-histochemical chan ges and to modifications in the ovarian, hepatic and serum lipid conce ntrations.