To study the metal composition of edible portion of farmed hybrid fish (Catla catla ♂ and × Labeo rohita ♀) in relation to body size and condition factor from Multan, Pakistan

Abstract

Samples of hybrid fish (Catla catla ♂ AND × Labeo rohita ♀) were collected during 2006. The contents of chromium, copper, iron, manganese, nickel and zinc in the edible tissue were determined by flame atomic absorption spectrophotometry (FAAS). Among the metal analyzed, Cu, Ni and Zn were the most abundant while Cr and Mn were below the detection limit. Iron was detected in few samples. The correlation coefficients between fish size (body weight and total length) and metal contents, i.e., copper, nickel and iron in edible part of fish were evaluated. The concentrations of copper and nickel in edible part of hybrid fish increased with total length and body weight while the zinc concentration showed a decreasing trend with total length and body weight, although the correlation was not significant. Metal concentrations were not significantly related with condition factor of fish in random samples but results were significant when relationship was observed in tight size ranges. The relationship among metals contents was also calculated. Overall, the levels of detected metals in the edible portion of the fish were low and well within the limits set by the FAO.