Effects of Aquaculture Substrate on Key Aquaculture Environmental Parameters, Growth Performance, and Physiological Responses in <i>Babylonia areolata</i>

To enhance the aquaculture environment of Babylonia areolata , this study evaluated five substrates—small ceramsite, medium ceramsite, large ceramsite, quartz sand, and river sand (control)—on water quality, growth, survival, digestive enzyme activity, and antioxidant capacity in juvenile B. areolata . Results demonstrated that small ceramsite achieved optimal performance in water quality maintenance, survival rate (92.4 ± 3.1%), and growth rate (specific growth rate: 1.85 ± 0.12%/day). Small ceramsite significantly enhanced lipase (18.7 ± 1.2 U/mg protein) and trypsin (23.4 ± 1.5 U/mg protein) activities in hepatopancreas compared to control (p &lt; 0.05). In contrast, large ceramsite exhibited lower digestive enzyme activity than control (p &lt; 0.05). Glutathione peroxidase (GSH-PX) activity in large ceramsite groups declined significantly (p &lt; 0.05), while lysozyme activity in hepatopancreas surpassed that in foot and mantle across all substrates. Conversely, acidic phosphatase (ACP) activity in mantle and hepatopancreas under large ceramsite was significantly lower than in foot tissues (p &lt; 0.05). Substrate type critically influences growth, immune function, and antioxidant capacity in B. areolata . Small ceramsite outperformed others by improving water quality, enhancing survival, and accelerating growth, while simultaneously boosting digestive and antioxidant enzyme activities. These findings suggest small ceramsite as the optimal substrate for B. areolata aquaculture, offering a strategy to optimize rearing conditions, improve economic efficiency, and promote mollusk health.