AMINO ACID STUDIES WITH JUVENILE Macrobrachium rosenbergii

Abstract This study reports the results of growth experiments with the freshwater prawn (Macrobrachium rosenbergii), using purified diets to establish the dietary requirements for lysine, arginine, methionine, and tryptophan. Four dietary levels of each amino acid were evaluated to determine quantitative requirements. The surprising outcome of these experiments indicated that these 4 amino acids were found dispensable for growth when omitted individually from the diets. Gut and/or tank bacteria may have supplied the prawns with amino acids in amounts sufficient for growth. These results suggest that searching for optimum amino acid levels for incorporation into cammercial diets may be less important than originally suspected. This would probably be particularly so where natural pond productivity provides prawns with many of their requirements.