Highlights
- Effects of warm temperature and/or low water pH were studied.
- Growth performance were negatively impacted.to either warm temperature or low pH exposure.
- Interactive exposure of warm temperature and low water pH induced high living cost of hybrid grouper.
- Hybrid grouper adjusted energy metabolism needs to cope with the changing environment.
Abstract
Rising of temperature in conjunction with acidification due to the anthropogenic climates has tremendously affected all aquatic life. Small changes in the surrounding environment could lead to physiological constraint in the individual. Therefore, this study was designed to investigate the effects of warm water temperature (32 oC) and low pH (pH 6) on physiological responses and growth of hybrid grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂) juveniles for 25 days. Growth performance was significantly affected under warm water temperature and low-pH conditions. Surprisingly, the positive effect on growth was observed under the interactive effects of warm water and low pH exposure. Hybrid grouper exposed to the interactive stressor of warm temperature and low pH exhibited higher living cost, where HSI content was greatly depleted to about 2.3-folds than in normal circumstances. Overall, challenge to warm temperature and low pH induced protein mobilization as an energy source followed by glycogen and lipid to support basal metabolic needs.
Thalib Y. A., Razali R. S., Mohamad S., Zainuddin R. A., Rahmah S., Ghaffar M. A., Nhan H. T. & Liew H. J., in press. Environmental changes affecting physiological responses and growth of hybrid grouper – the interactive impact of low pH and temperature. Environmental Pollution. Article (subscription required).
