Optimun Supplemental Level of L-Ascorbyl-2-Phosphate-Mg to Diet for White Shrimp Penaeus vannamei

Abstract

A stable form of ascorbic acid, L-ascorbyl-2-phosphate-Mg (APM), was tested to confirm the effect of APM on juvenile shrimp P. vannamei and determine the optimun supplemental level to diet. Shrimp, weighing 1.10±0.15 g, were fed 5 diets containing graded levels of supplemental APM (0, 10, 18, 33, and 66mg/100g diet) for 18 weeks. Shrimp fed the unsupplemented diet showed deficiency symptoms such as high mortality, molting frequency reduced, and blackened lesions under the exoskeleton, on the abdomen, on the carapace, in the gills and in the foregut. These symptomswere similar to the proposed ascorbic acid deficiency symptoms which is named “black death.” The results of the feeding trials indicated that the supplementation of 10mg APM per 100 g diet was sufficient for a better survival and prevention of clinical signs of vitamin C deficiency symptom in P. vannamei.