Feeding Response of Brown-Marbled Grouper (Epinephelus fuscoguttatus) Juveniles to an Amino Acid Mixture: A Preliminary Study of Identifying Feeding Stimulant for Grouper Culture

The present study examined the feeding response of juvenile brown-marbled grouper (Epinephelus fuscoguttatus) to an amino acid mixture (AAM). The findings contribute to identifying potential feeding stimulants (FS) for grouper aquaculture. Agar gel pellets were used to deliver the AAM at concentrations of 0% (pure agar gel-PAG), 0.01%, 0.1%, and 1.0% to the fish. The fish's feeding responses were recorded and analyzed, and their preference indices (ranging from 0 to 1) for the AAM were calculated. The PAG pellet was completely rejected by the fish (preference index = 0). This result indicates that any substance added to the agar gel pellets that induce the fish to consume them can be considered a potential feeding stimulant. On the other hand, the AAM was generally well accepted by the fish (preference indices ranging from 0.46 to 1), with the 1% AAM treatment achieving the highest preference index. These results confirm that the AAM is an effective FS for grouper juveniles. Further research on the fish's taste preferences for individual amino acids is strongly recommended to optimize the formulation of the feeding stimulant.