Pengaruh Waktu Pemberian Pakan Buatan terhadap Kelangsungan Hidup Larva Rajungan (Portunus pelagicus) :Hubungannya dengan Perkembangan Aktivitas Enzim Pencernaan

Abstract

Seed production of portuned crab still face problems of lower survival rate when being fed on artificial diet at the early larvae stage. Therefore, this experiment was conducted to examine the precise time for feeding artificial diet and its relation to development of digestive enzyme activity of swimming crab larvae (Portunus pelagicus). Five different treatments related to initial feeding were examine. Treatment A larvae were fed live food from Zoea (Z)1 to megalopal stage. Treatment B larvae were fed artificial diet from Z1 stage to megalopal stage. Treatment C, D and E larvae were fed live food at Z1 stage and shift to the artificial diet at Z2, Z3 and Z4 stage respectively. Survival rate, intermolt period, and digestive enzyme activity were used at evaluating parameters. Results of this experiment showed that larva fed on artificial diet at Z1, Z2, Z3 could not develop to reach FC stage. The enzyme activity of protease was high in Z1 larvae and tend to decrease during larva development. Whereas the enzyme activity of amylase and lipase were lower in Z1, and tend to increase during larva development. The highest improvement of enzyme activity of amylase and lipase were started from Z4 to megalopal stage. From this research it was concluded that the first feeding time of commercial feed to larva affect the survival rate of FC, and the precise time for feeding the larvae with commercial feed was at Zoea 4 stage.