Optimal feeding frequency for intensive indoor culture of pharaoh cuttlefish (Sepia pharaonis)

In order to optimize the indoor scale artificial culture of Sepia pharaonis , this study compared the growth performance, composition of body components, activity of digestive enzymes, and intestinal microorganisms of S. pharaonis under different feeding frequencies, 1 time/day (T1), 2 times/day (T2), and 3 times/day (T3). The results showed that the feeding frequency had a significant effect on the growth performance, body composition, digestive enzyme activity and intestinal microorganisms of the S. pharaonis . The T3 group exhibited significantly higher survival rate, specific growth rate, weight gain rate and feed conversion ratio compared to other groups, reaching 30.76 %, 15.05 %, 31.19 % and 41.05 %, respectively. The T2 group showed the highest protein content and lowest lipid content in body composition. Digestive enzyme analysis revealed maximum amylase and protease activities in T2, while lipase activity peaked in T3. Intestinal microbiota characterization indicated a healthier and more stable microbial environment in T2. In conclusion, we suggest that the S. pharaonis (juvenile stage) cultured in the indoor cement pool environment, if the pursuit of yield, choose to feed 3 times/day, if the pursuit of quality and cost control, choose to feed 2 times/day. These findings provide crucial theoretical guidance for optimizing feeding strategies in S. pharaonis aquaculture systems. • 3 times/day feeding can increase the survival rate, specific growth rate and weight gain rate of Sepia pharaonis. • 2 times/day feeding can increase the protein content of Sepia pharaonis . • Feeding frequency could significantly affect the activities of α-amylase, lipase and trypsin of Sepia pharaonis . • Optimal feeding frequency can improve the health of intestinal microorganisms in Sepia pharaonis.