VITAMIN-C REQUIREMENTS OF THE SHRIMP PENAEUS-VANNAMEI

Two experiments were conducted to investigate vitamin C requirements o f the shrimp Penaeus vannamei using L-ascorbyl-2-polyphosphate (APP) i n semi-purified diets. Shrimp survival but not growth was significantl y (P < 0.05) reduced by feeding vitamin C-deficient diets. Whole-body ascorbic acid (WBAA) content in shrimp increased as dietary vitamin C increased. After shrimp were fed a vitamin C-free diet for 3 weeks, th e depletion levels for WBAA of shrimp were found to be 2.6 and 4.8 mug /g for shrimp with an initial weight of 0.1 and 0.5 g, respectively. M inimum dietary vitamin C levels required for normal survival of P. van namei were estimated to be 120 mg ascorbic acid-equivalent (AAE)/kg di et for shrimp with an initial weight of 0.1 g and 41 mg AAE/kg diet fo r shrimp with an initial weight of 0.5 g. Dietary vitamin C levels of 120 and 90 mg AAE/kg were required for maintaining a normal WBAA conte nt in shrimp with an initial weight of 0.1 and 0.5 g, respectively. Th ese data indicated that dietary vitamin C requirement of P. vannamei d ecreased with increased size.