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

Abstract

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 1/2^nd and 1/5^th 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 5^th 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 2^nd of LC₅₀ concentration. A significant increase in the catalase activity was recorded at 7^th 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 28^th 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.