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Prokaryotic and eukaryotic organisms contain heat shock proteins (HSPs), crucial for rapid response to environmental stress. However, their specific roles in different stress conditions are not fully understood. This study investigated HSP70 and HSP90 expression in H. diversicolor squamata, using qRT-PCR. Data analysis employed SPSS, including t-tests and ANOVA, with significance set at P < 0.05. Results showed distinct expression patterns of HSP genes under varying TSS levels. Both HSP70 and HSP90 mRNA levels significantly increased in response to TSS stressors, with HSP70 exhibiting the highest sensitivity to TSS changes. The duration and amount of TSS exposure influenced gene transcripts, particularly notable at 12 hours and 150 mgL-1 concentration. These findings suggest HSP genes play a role in cellular stress responses to environmental stimuli. HSP70 and HSP90, sensitive to TSS stress, can serve as biomarkers for assessing stress levels from TSS exposure and detecting TSS contamination in abalone farming.

After the yolk sac of fish larvae is absorbed, they will utilize external food sources such as natural phytoplankton and zooplankton. Specifically, one of the zooplankton species used is the small-sized rotifer Brachionus sp., which matches the mouth opening of the larvae. The purpose of the experiment was to examine the effects of providing live rotifer in combination with artificial feed on the survival rate and growth of Nile tilapia (Oreochromis niloticus) larvae in high salinity conditions. The Nile tilapia larvae used in the experiment were the offspring of Red Nifi strain breeders raised in freshwater and still containing yolk sacs. Feeding commenced after the yolk sacs were absorbed, and the salinity was gradually increased to 25-30 ppt. The larvae were fed with rotifers for seven days (P-1), 14 days (P-2), and then continued with another type of artificial feed. There was also a control group that only received artificial feed without rotifers. The stocking density of the fish larvae was 25 individuals per liter, and the total water volume used was 15 liters. The rotifer dose was maintained at 10-20 individuals per milliliter of water per day during the 4-week rearing period. The results showed that providing rotifers in water salinity between 10-15 ppt during the first seven days resulted in a survival rate of > 80%, whereas the control group achieved > 90% survival. However, the survival rate of the larvae started to decline from the second seven-day period with the increase in salinity between 15-25 ppt, and it continued to decrease to < 60% until the fourth week for all treatments.

The effect of Inulin derived from Dahlia tubers as a functional diet on the growth of white legs shrimp was studied to see its impact on AHPND infection. The research was conducted in a fiber tank filled with 500 L of seawater sterilized with chlorine and stocked with 100 PL30 shrimps/container. Shrimp were treated with feed containing Inulin extract from dahlia tubers at a dose of 2.5%, 5.0%, and 5.0% commercial Inulin and compared with a control. Each treatment was given 2 replications. Shrimp were then challenged with Vibrio parahaemolyticus strain AHPND at a density of 106 CFU/mL. The live shrimp were then processed histopathologically to view the microanatomical gut structure (midgut). The results showed that the mean survival of the shrimp in the control and 2.5% Inulin treatment groups was 97.3 ± 1.15% and 97.3 ± 2.3%, respectively, and the 5% Inulin treatment and commercial Inulin were each 96.9 ± 2.7%. Histopathological observations on Inulin treatment of 2.5% dahlia tuber extract and commercial Inulin showed that shrimp intestine had more lactic acid bacteria abundance than control and 5% Inulin extract. In conclusion, shrimp treated with inulin can reduce the risk of shrimp being infected with AHPND.