Influence of ambient oxygen on respiratory and substrate level metabolism in freshwater fish, Cirrhinus mrigala

Abstract

In the present study experiments were conducted to find out oxygen consumption, ammonia excretion and ammonia quotient (AQ) in a freshwater fish, Cirrhinus mrigala acclimated sand tested at 28 + 1 oC, subjected to hypoxic condition. The rate of oxygen consumption in Cirrhinus mrigala a normoxia and hypoxia at normoxia was 145.2 mg/kg/hr, which decreased with the duration of experiment and decrease in ambient oxygen consumption from 5.2 to 3.6 mg/l was found to be higher than that of under hypoxic condition. The normoxic rate of ammonia excretion was found to be 26.19 mg/kg/hr and the hypoxic rate of ammonia excretion was observed range of 4.82 to 5.3 mg/kg/hr. Lactic acid in muscle, gill and liver tissues were found to be 122.61, 23.20 and 26.81 m. mole/g respectively, whereas the hypoxic lactic acid content in muscle, gill and liver tissues were found to be 226.72, 30.94 and 50.90 m.mole/g respectively.