Comparison of vitamin C requirement for maximum growth of grass shrimp, Penaeus monodon, with L-ascorbyl-2-monophosphate-Na and L-ascorbyl-2-monophosphate-Mg

A growth experiment was conducted to quantify the level of L-ascorbyl-2-monophosphate-Na (C2MP-Na) needed to satisfy the dietary vitamin C requirement for juvenile grass shrimp, Penaeus monodon. L-Ascorbyl-2-monophosphate-Mg (C2MP-Mg) was also included in the study for comparison. Purified diets with seven levels of ascorbic acid (0, 30, 70, 150, 300, 600 and 1,200 mg/kg diet) from either supplemental C2MP-Na or C2MP-Mg were each fed to triplicate groups of P. monodon (mean initial weight: 0.55 +/- 0.04 g) for 8 weeks. Results of the broken line analysis indicated that the adequate dietary ascorbic acid from each source for growing shrimp was 106.1 mg of C2MP-Na/kg (equivalent to 26.7 mg of ascorbic acid/kg) diet and 48.4 mg of C2MP-Mg/kg (equivalent to 22.5 mg ascorbic acid/kg) diet, and it also indicated that C2MP-Na was about 84% as effective as C2MP-Mg in meeting the vitamin C requirement for P, monodon. Hepatopancreatic ascorbic acid concentrations generally reflected the level of ascorbic acid supplementation in the diet. Dietary levels of 162.2 mg C2MP-Na/kg and 144.2 mg C2MP-Mg/kg were required for hepatopancreas tissue saturation. (C) 1998 Elsevier Science B.V. All rights reserved.