CHANGES IN LIPID CONTENT OF OYSTER, CRASSOSTREA CATTUCKENSIS DURING ACCUMULATION AND DEPURATION OF MERCURY

ABSTRACT -The oysters, Crassostrea cattuckensis were exposed to sublethal levels of mercury for 15 days for metal accumulation and next 15 days of metal detoxification. During 15 days metal exposed oysters to 0.01 and 0.04 ppm concentrations there was increased lipid significantly in all body parts when compared to experimental control. The increased rate upon 15 days in low concentration was from gonad (102.76), mantle (48.80), hepatopancreas (46.39), gill (45.72), adductor muscle (41.01) and siphon (22.75). While in high concentration was from gonad (112.07), mantle (90.91), gill (84.77), adductor muscle (78.78), siphon (71.57) and hepatopancreas (60.85) when it was compared with control. Further, the content increased more in siphon (39.77) followed by mantle (28.95), gill (26.80), adductor muscle (26.79), hepatopancreas (9.88), gonad (4.60) when it was compared with low concentration group. Whereas, during detoxification process the lipid was more increased significantly in 0.0lppm from mantle (8.69) followed by adductor muscle (8.53), hepatopancreas (6.44), gill (5.59), siphon (5.53) and gonad (1.92). In 0.04 ppm from siphon (54.20), hepatopancreas (22.05), adductor muscle (20.99), gonad (20.45), gill (15.35) and mantle (12.22) when compared with experimental group. On the other hand the lipid was more decreased among all the body parts of oysters when compared with respective metal concentration group of 15 days exposed to metal. The decrease trend was in 0.01 ppm from gonad (45.75), mantle (25.88), gill (25.82), hepatopancreas (25.11), adductor muscle (15.57), and siphon (4.25). In 0.04 ppm it was from mantle (40.65), gonad (38.70), gill (36.09), hepatopancreas (26.41), adductor muscle (25.76) and siphon (0.56).