Toxicological Effect of Water-Borne Fe+Zn Mixture on Catalase Activity of Cirrhina mrigala and Labeo rohita

This study was conducted to assess the effects of the water-borne Fe+Zn mixture on the catalase activity in the different organs of Cirrhina mrigala and Labeo rohita. 90-day old fingerlings of both fish species were exposed to 1/2nd and 1/5th of their respective 96-hrs LC50 concentrations of Fe+Zn mixture, separately, at constant temperature (280C), pH (7.5), and total hardness (225mgL-1). Fish sampling from each treatment was done after 7, 14, 21, and 28 days of Fe+Zn mixture exposure and their organs viz. liver, kidney, gills, and muscles extracted for catalase enzyme assay. The maximum catalase activity in Cirrhina mrigala was observed at 1̸ 5th of Fe+Zn mixture LC50 exposure as 996.87±102.23UmL-1, while in Labeo rohita it was 1013.43±103.50 UmL-1 at 1̸ 2nd of LC50 concentration. A significant increase in the catalase activity was recorded at 7th day of exposure as 1083.66±7.29 and 1091.08±22.15 UmL-1 in Cirrhina mrigala and Labeo rohita, respectively while it was significantly lower at 28th day of Fe+Zn mixture exposure. Among the organs, the catalase activity varied significantly as liver kidney muscles gills in Cirrhina mrigala and Labeo rohita. Significantly higher catalase activity was recorded in Labeo rohita as compared to Cirrhina mrigala.