Effect of a Sublethal Concentration of Zinc Sulphate on the Growth Rate of Fingerlings of Channa punctatus (Bloch), a Freshwater Murrel

Fingerlings of Channa punctatus are exposed to 12 mg/l zinc sulphate for 31 d at daily feeding. From the 19th day a significant decrease of growth (increase of weight) by 7 … 8 % as compared with the untreated control fishes was found. After exposure for 30 d the RNA- and protein-contents of the muscles are lower by 10 and 13 %, respectively.