Response of hatchery-cultured mud crab (Scylla paramamosain) instar fed natural preys and an artificial feed

Abstract

A 60 day feeding trial was carried out to evaluate the effect on growth, survival, amino acid composition, and coloration of hatchery-cultured mud crab (Scylla paramamosain) instar (0.41 ± 0.05 g) fed: fish Harpadon nehereus, Chinese mystery snail Cipangopaludina chinensis, and artificial feed. Each food type was assigned to eight tanks (10 crabs per tank). Results showed that the growth of mud crab is significantly affected by food type. Crabs fed the artificial feed showed specific growth rate comparable to crabs fed the snail C. chinensis, and higher growth rate compared to crabs consuming fish H. nehereus. Amino acid profiles of whole crabs were found to be highly correlated with dietary amino acid profiles. Crabs fed dry feed showed higher L* value (lighter colour) and b* value (higher intensity in blue colour) compared to crabs fed the other two diets. In conclusion, it is clear that artificial feed is potentially an alternative diet for hatchery-cultured mud crab (S. paramamosain) instar in terms of growth rate. However, it is suggested that paler carapace color might be related to insufficient dietary intake of carotenoids from the artificial feed