Biochemical Study of Freshwater Fish Catla catla with Reference to Mercury Chloride

Toxic activity of mercury chloride was tested in vivo on fresh water fish Catla catla. Acute toxicity testswere conducted to measure the impact of toxicity on the fishes within a short period at the variousconcentrations of HgCl2 (0.1, 0.5, 1, 1.5, 2, 2.5 and 3mg/L). The protein and carbohydrate were estimatedusing Anthrone by standard methods and enzymes such as Na⁺-K⁺ , Mg₂₊ and Ca₂₊ adenoxidetriphosphatases were determined caloriemetrically. Depletion of protein was observed at all exposureperiods. The biochemical estimation values of carbohydrates in muscle, intestine and brain showedsignificant values with P<0.05. The activity of Mg²⁺ adenoxide triphosphatases in muscle, intestine andbrain was studied and the maximum depletion was observed at 96h, 72h and 72h, respectively. Regardingactivity of Ca²⁺ adenoxide triphosphatases in muscle, the maximum depletion of this enzyme activity inmuscle was observed at all exposure periods, except 96h. In intestine, enzyme activity was graduallydecreased in all exposure and an increase was found during 96h. In brain, the enzyme activity wasobserved at all exposure periods except 96h.