Effect of vitamin C derivatives on the performance of larval kuruma shrimp, Marsupenaeus japonicus

This study was conducted to determine the effect of two vitamin C (Ascorbic acid, AsA)sources; L-ascorbyl-2-monopliosphate-Mg (AMP-Mg) and L-ascorbyl-2-monophosphate-Na/Ca (AMP-Naf Ca), on larval kuruma shrimp performance, i.e.. percentage survival (%S), developmental stage (DS). the number of larvae metamorphosed to the postlarval stage (%PL), body weight (BW), total body length (TL), tolerance against formalin stress (LT50). and whole body ascorbic acid concentration in shrimp, (WBAA). Seven different levels of two vitamin C sources. 0. 23, 223. 695. 1034. 1819. and 2240 mg/kg diet for AMP-Mg and 0, 48, 198. 614, 1134, 1817, and 2494 diet"-2 diet for AMP-NI-af Ca were incorporated in kappa-carrageenan nucrobound diets (MBD), and each MBD was fed to five replicate groups of the larvae from zoea, stage up to postlarval stage for 11 days. There were no differences between AMP-Mg and AMP-Na/Ca on %S. DS. BW and TL under the similar AsA level. However, significant differences were found in %S. DS. %PL. and BW among the groups fed diets containing the different levels of AsA supplementation in both AMP-Mg and AMP-Na/Ca groups (P<0.05). Whole body AsA concentration increased with increased dietary AsA level. Shrimp fed the higher AsA diet survived longer than those fed AsA-free or lower AsA diets in both groups when exposed to the formalin stress. The optimum dietary AsA level for kuruma shrimp larvae were 71 and 43 mg AsA/kg diet when AMP-Mg and AMP-Na/Ca were used, respectively, based on the broken-line analysis. The minimum AsA concentration in shrimp whole body with 22 mug/g wet weight might be required to produce the high-quality postlarvae which could tolerate a stressful condition. (C) 2004 Elsevier B.V All rights reserved.