Abstract

In this study, relationships of body size with metals; zinc (Zn), iron (Fe), copper (Cu), nickel (Ni), cobalt (Co), cadmium (Cd) and lead (Pb) [AI1]in freshwater wild Wallago attu (whole fish) was studied. Mean concentrations (μg g^-1 dry weight) of the metals in carcasses of wild W. attu were found to be 23.66 (Cu), 96.33 (Zn), 94.02 (Fe), 0.55 (Ni), 1.05 (Co), 0.31 (Cd) and 2.07 (Pb). Cr concentration was below the limit of detection of the technique. It was observed that all metals showed significant positive correlation (p P< 0.001) with total body weight or total body length. Metals such as Cd, Co, Cu and Fe were found to increase in direct proportion to an increase in body weight showing isometry (when b=1 or not significantly different from 1.0). Ni, Zn and Pb were found to decrease with the increase of body weight showing negative allometry. All the metals had decreasing trends with the increase of total length of the fish showing positive allometry (b value more than 3) except Zn.

Key words: Allometry, body weight, correlation, metals, Wallago attu.

Abbreviation

Zn, Zinc; Fe, ion; Cu, cupper; Ni, nickel; Co, cobalt; Cd, cadmium;Pb, lead; Cr, chromium.