Effect of calcium and enzyme involvement to survival rate and development of the early stage zoea Portunus pelagicus

Abstract

The early stage of blue swimming crab (Portunus pelagicus) zoea requires calcium for calcification after molting which can be drawn from water and its diet. However, the digestive system of the early stages of the larvae is still not perfect, so the ability to digest food is limited. Calcium and enzyme inclusion in its formulated diet is important to aid the calcification process. Therefore, in this study, the effect of calcium and enzyme inclusion to survival rate and development of the zoea were examined. Zoeas were fed with nauplii Artemia and three levels of calcium Kalzana-D without enzyme Enzyplex inclusion (At, Bt and Ct) and with enzyme Enzyplex inclusion (AtE, BtE and CtE). There were three replicates in each treatment that had 100 zoeas in 2-L plastic tube on 30°C water bath. The result revealed that 50 mg calcium with enzyme involvement supported the early stage of zoea to molt and develop to the next stage. In addition, calcium inclusion with or without enzyme involvement promoted survival rate of the zoea.