Effects of different feeding regimes on larvae and crablets of purple mud crab, Scylla tranquebarica (Fabricius, 1798)

Abstract

This study aims to compare the rearing of purple mub crab, Scylla tranquebarica larvae with different feeding regimes. This study consisted of two treatments, namely Treatment A (rearing of mud crab larvae without artificial feed) and Treatment B (rearing of mub crab larvae with artificial feed starting at Zoea 3 to the crablet stage) each with three replications. The rearing tanks used from Zoea 1 to Megalopa (M) stages were cylindrical fiberglass tanks with 0.65 m in the diameter and 200–250 liter volume. Each tank was stocked with newly hatched larvae at a density of 50 larvae L−1. The results showed that Treatment A had better survival rate (from Zoea 1 to crablet) and crablet production namely 0.51% and 138 respectively compared with Treatment B namely 0.27% and 121 respectively but there was no significant difference (P>0.05). Although the survival rate on Treatment B was lower but the percentage of megalopa stage appearance and the Larval Stage Index value on 18–20 days after hatching of Treatment B were higher than Treatment A. Based on the results of this present study, rearing of Zoea 3 to Zoea 5 and M is still sufficient by using only enriched Artemia nauplii (with High Unsaturated Fatty Acid (HUFA) as much as 80 ppm). For the rearing of larval Zoea 5 and M to crablet, besides fed with Artemia nauplii can also be fed with additional feed in the form of fresh feed (shredded shrimp meat) or artificial feed that used in shrimp post larval rearing.