TOXICITIES OF TWO METALS AND TWO PESTICIDESTO GRASS CARPS AT DIFFERENTDEVELOPMENT STAGES
两种金属和两种农药对草鱼不同发育阶段的毒性效应

The effects of Cd, Cu,BHC and parathion on hatching rate of grass carp (Ctenopharyngodon idellus) were evaluated. The results indicated that the 96-hour EC50 were 0.078 mg/L for Cd, 0.17 mg/L for Cu, 1.0 mg/L for both BHC and parathion. The teratological symptoms appeared included kyphosis, yolk sac hydrops and tubular heart.The sensitivities of the fish at different development stages were also found to be different. The 96-hour LC50 were 0.1-0.5mg Cd/L and 0.3-0.5 mg Cu/L for embryo, 0.34 mg Cd/L and 0.11 mg Cu/L for 10 days fry and 8 mg Cd/L and 0.59 mg Cu/L for 120 days juvenile grass carp, respectively.