Growth is a fundamental and vital characteristic of abalone, regulated by both cell number and size, and modulated by growth-related genes. The mollusk-like growth factor (MLGF) is a secreted protein that plays a key role in the growth and development of Pacific abalone. In this study, the growth-specific expression of Hdh-MLGF were analyzed under different conditions commonly encountered by Pacific abalone in aquaculture systems. The expression of Hdh-MLGF varied significantly with growth patterns, showed higher expression in rapid-growing individuals and lower expression in slow-growing abalone. Under starvation conditions, Hdh-MLGF expression was downregulated as the duration of starvation progressed. Under thermal stress, Hdh-MLGF expression increased during the first 12 hours at 25 °C stress. However, at 30 °C, the highest expression was recorded after 6 hours of thermal stress. These results provide valuable insights for future research on this growth factor in abalone and its aquaculture management.

Introduction
Materials and methods
    1. Abalone culture and growth-specificsample collection
    2. Tissue samples from starved Pacificabalones
    3. Tissue samples from Pacific abalonessubjected to heat stress
    4. Extraction of total RNA and cDNAsynthesis
    5. Primer design and qRT-PCR analysis
    6. Statistical analysis
Results
    1. Growth-specific expression pattern ofHdh-MLGF in Pacific abalone
    2. Expression of Hdh-MLGF during starvationand refeeding in Pacific abalone
    3. Thermal stress influences Hdh-MLGFexpression in Pacific abalone
Discussion
Conflicts of interest
Data availability
Authorship contribution
References

• Kang Hee Kho(Department of Fisheries Science, Chonnam National University, Yeosu, 59626, South Korea) Corresponding author
• Won-Kyo Lee(Department of Fisheries Science, Chonnam National University, Yeosu, 59626, South Korea) Corresponding author
• Yusin Cho(Department of Fisheries Science, Chonnam National University, Yeosu, 59626, South Korea)
• Doo-Hyun Cho(Department of Fisheries Science, Chonnam National University, Yeosu, 59626, South Korea)
• Hanif Md Abu(Department of Fisheries Science, Chonnam National University, Yeosu, 59626, South Korea)