Preliminary evaluation of seaweed of Ulva lactuca as supplemental diet for sea cucumber, Holothuria scabra, in aquaculture

Abstract

The seaweed Ulva lactuca was evaluated as a food supplement for sea cucumber Holothuria scabra. The aim of this study was to examine the relationship between forms/texture of feed, ingestion rate and feces production rate of H. scabra. Ten individuals of H. scabra were placed in ten 20 L glass aquariums with continuous aeration. The sea cucumbers were divided into two groups: Group A (A1, A2, A3, A4, and A5) and Group B (B1, B2, B3, B4, and B5). The average initial weight of sea cucumber in Group A was 387.46 g (±2.33 g) while in Group B was 383.74 g (±3.56 g). Group A sea cucumbers were fed with 2.5 g of raw (natural form) U. lactuca, while Group B were fed with 2.5 g blended (mechanically shredded) U. lactuca. The ingestion rate (IR) for Group A was 0.01 g ind^-1 d^-1 (±0.02 g ind^-1 d^-1) while Group B was 0.33 g ind^-1 d^-1 (±0.08 g ind^-1 d^-1). The fecal production rate (FPR) for Group A was 0.05 g ind^-1 d^-1 (±0.01 g ind^-1 d^-1) and Group B was 0.11 g ind^-1 d^-1 (±0.03 g ind^-1 d^-1). From this study, it can be concluded that feeding H. scabra with blended form of U. lactuca seaweed has the most potential to be utilised as supplemental feed.