Sub-lethal toxicity of copper and cadmium on the total hemocyte count and serum phenoloxidase activity pattern in the Indian white shrimp Fenneropenaeus indicus (H. Milne Edwards, 1837); Effects of individual metals

The presence of toxic chemicals especially heavy metals in the environment has been a great threat to the aquatic animals worldwide. Investigations on the short-term (96 h.) toxic effects of copper and cadmium at sub-lethal concentrations on total hemocyte count (THC) and serum phenoloxidase (PO) activity in the marine shrimp, Fenneropenaeus indicus are reported in this paper. Changes in the THC and PO activity were determined in relation to time of exposure and concentrations of the metals used. The results showed that the decrease in the THC and PO activity values in the shrimp exposed to metals were rapid and transient. The values improved during the end of the experiment in case of both the metals. The rapid development of hemocytopenia and decreased PO activity was more conspicuous in case of shrimp exposed to cadmium than those exposed to copper.