Energy Budget in Terms of ATP, ADP, AMP, and Energy Charge In The Osmoregulatory Tissues of Indian Major Carp Catla catla (Hamilton) Under Thermal-Stress And Thermal-Adaptation

Abstract

The heat-adapted (32°C) Catla catla registered as increased level of ATP and energy charge with concomitant lower levels of ADP, and AMP when compared to cold-adapted (22°C) fishes. All the osmoregulatory tissues like the gill, kidney, and intestine indicate greater ATP turnover adaptation to higher temperatures. In order to differentiate thermal stress from thermal adaptation, the 22°C adapted were readapted to a temperature change of 22°C 32°C at the rate of 1°C/hour as in the case of stress and at the rate of l°C/ 60 hrs as in the case of adaptation During the time course of experiments there is a gradual stepping-up in the levels of ATP and energy charge and a gradual stepping-down in ADP and AMP in all tissues. Further, there is a complete filling-up process in ATP and values reached gradually the original level of these parameters of the control of 32°C adapted fishes. The heat-adapted fishes exhibited a fairly good amount of recovery ranging from 83% to 88% in these adenylate nucleotides. On the other hand, in the temperature-stressed fishes the adenylate nucleotides did not reach the control values and the filling processes with ATP could not be completed. Further, the % recovery in these parameters is far less 47 % to 57%, when compared to temperature adapted fishes. The continuous thermal-stress (1°C/hour) action upon this fish Catla catla resulted in stress-adaptation (adaptation resulted due to stress).