Effect of sublethal concentrations of some pesticides on the growth and survival of the fingerlings of the African catfish - <i>Heteroclarias</i>" (hybrid)

Abstract

Fingerlings of "Heteroclarias" (hybrid) were exposed to sublethal concentrations of thiodon (Organophosphate), Malathion (Organophosphate ), and carbaryl (organocarbamide) for a period of 21 days in a static bioassay. The rate of feeding, food conversion and the efficiency of absorption and conversion decreased with increasing concentrations of the pesticides. Protein, carbohydrate and lipid  contents of muscle, liver, gill and intestine in "Heleroclarias" also decreased when the fish were exposed to maximum sublethal concentrations of the pesticides. A comparative analysis of the efficacy of the three pesticides reveals that the growth rate of "Heleroclariase" was drastically reduced on exposure to thiodon Pesticides.

Key Words: "Hateroclarrias" Pesticides, sublethal Growth and survival.