Effect of Environmental acidic pH on Oxygen Consumption in Different stages of Fish, Cyprinus carpio(L)

Abstract

The data in table 1 and 2 showed changes in the total respiration and unit oxygen consumption of the developmental stages of fresh water fish during short-term exposure and acclimation to sub lethal acidic (pH 5.5) media. The oxygen consumption of fry significantly depleted in all the days of exposure to sub lethal acidic pH 5.5 starting from first day to fourteen days of exposure. The rate of total oxygen consumption depletion was higher in second day followed by fourth and sixth day with a gradual decreased trend was observed in the depletion up to fourteenth day of exposure. Similarly it is also observed significant decrease of total oxygen consumption and also rate of oxygen consumption of fingerling on exposure to sub lethal acidic pH in all the days of exposure, i.e., first day to fourteenth day when compared to control. The unit oxygen consumption of fry and fingerling on exposure to sub lethal pH media exhibited significant depletion when compared to control. The rate of depletion was more in the initial days of exposure and it was reduced gradually in 12 th and 14 th days of exposure. Further, the animal excretion was highly depleted in acclimated fry to sub lethal acidic media when compared to control. Similarly, excretory pattern of the fingerling also showed significant reduction on acclimation to sub lethal acidic medium over control. The tissue ammonia levels were also significantly depleted in both fry and fingerlings on acclimation to sub lethal acidic medium when compared to control (table 3). But the rate of depletion was more in fingerlings than to fry stage. It is concluded that the acclimation processes to sub lethal acidic medium induced compensatory changes in nitrogenous end products metabolism of fry and fingerlings while providing positive survival capacity under acidic stress conditions.