Sublethal effects of heavy metals on biochemical composition and their recovery in Indian major carps.

Studies were conducted to assess the effects of sublethal exposure of heavy metals cadmium, arsenic and zinc for 45 days on Indian major carps, Labeo rohita, Cirrhinus mrigala and Catla catla. Heavy metal treatments in general showed significant reduction in carbohydrate and lipid contents content in muscles as well as in gills in all the three fish species. The order of reduction of muscle and gill carbohydrate and lipid content due to different treatments was Cd+As+Zn>Cd+As>As+Zn>Cd+Zn>Cd>As>Zn. When fish were transferred to metal free water for 30 days, the level of carbohydrate and lipid contents improved considerably in all the three fish species.