| Abstrak/Abstract |
An increase in temperature can be a significant stressor for aquatic organisms. Abalones, a
type of single-shelled gastropod, are the most important commercial species in shellfish cultivation in
Indonesia. To evaluate the potential ecological risks posed by temperature stress, we measured
biological responses such as survival rates, mucus production, muscle hardness and histologically foot muscle abnormalities in Haliotis squamata. In addition, biochemical responses and gene expression profile were also evaluated in the exposed experiment to various temperature gradients. Thermal shock was carried out in 4 rectangular glasses aquarium (100 L). Abalones were divided into four groups for temperature treatment, in triplicates. The temperature treatments ware adjusted to 28, 30, 32 and 34?C in advance. Every aquarium contained 3 pcs of 20 cm long 3” PVC pipe for rearing 30 abalones 32.97±1.83 mm per PVC. Following 4 days of temperature exposure, the dead abalones were collected from each aquarium, after which the number of surviving abalones in each aquarium was recorded. These results represented the survivorship at 24, 48, 72, and 96 h. Abalone hemolymph were collected randomly by 1 mL 25 gauge microsyring at 0, 6, 12, 24, 48, and 96 hours. The hemolymph samples were stored in -20?C until analyzed. Increase in temperature stress triggers more mucus production and hardness of the muscle and abnormal foot muscle structure. Furthermore, antioxidant enzyme activity increased in abalone exposed to relatively lower and higher temperatures (28, 32 and 32?C). Super oxide dismutase, catalase and phenol oxidase activity were determined in a time-dependent manner after high temperature pressure. Generally, production of heat shock 70 and 90 proteins also increased significantly in H. squamata which were treated in temperatures gradient (more than 30?C) for 6-12 hours. These results provide valuable information about the stress response to increasing temperature in H. squamata. |
