Requirements of juvenile marine shrimp, Penaeus monodon (Fabricius) for lysine and arginine

Feeding experiments were conducted using amino acid test diets to determine the dietary requirements of juvenile Penaeus monadon for lysine and arginine. Two sets of the test diets were prepared. The natural protein was supplied by casein and gelatin. Crystalline L-amino acids were added to provide an amino acid profile similar to shrimp muscle protein except for the test amino acid. One set of experimental diets contained graded levels of lysine at 1.18-3.28% of the diet and another set contained arginine at 0.6-3.0% of the diet. The amino acid mixture was pre-coated with carboxymethylcellulose (CMC) and diets were further bound with CMC, cornstarch, and K-carrageenan to prevent leaching losses of amino acids. Shrimp postlarvae, PL20, with mean weight of 21 +/- 0.5 mg, were randomly distributed at 10 shrimp per tank in 40-1 fiberglass tanks and reared on the diets for 50-56 days. Growth, survival and feed conversion efficiency were determined at termination of feeding trials and signs of nutritional deficiency noted. Lysine and arginine requirements were determined from relationships between weight gains and dietary lysine and arginine levels as analyzed by the broken-line regression method. The requirement of juvenile P. monodon for lysine was estimated to be 2.08% of the diet or 5.2% of dietary protein while the requirement for arginine was 1.85% of the diet or 5.3% of dietary protein. This information is crucial in formulating cost-effective practical diets for juvenile tiger shrimp. (C) 1998 Elsevier Science B,V. All rights reserved.