Conclusions
In conclusion, INO was the most potent feeding stimulant for the juvenile O. marmoratus as it was still effective to promote fish ingestion even at low concentration 0.001 M. IMP•Na2 was an effective feeding stimulant for the fish only at the concentration level of at least 0.1 M. Higher concentration of GMP•Na2 (>0.1 M) may be required to improve its efficiency as the feeding stimulant. Taurine was not a feeding stimulant, and betaine was neither a feeding stimulant nor feed enhancer to the juvenile O. marmoratus. Further study should be conducted to evaluate the effectiveness of dietary INO supplementation to improve the pellet-weaning progress of juvenile O. marmoratus.