Neurotransmitters induce larval settlement and juvenile growth of the sea cucumber, Holothuria scabra

Abstract The sea cucumber, Holothuria scabra, is a high-value economic animal in Thailand for local consumption and exportation. One major drawback in aquaculture of this species is that their larvae have low settlement and survival rates during the early developmental period. In the present study, we investigated the effects of various neurotransmitters, including GABA, dopamine (DA), L-DOPA, and monosodium glutamate (MSG) on larval settlement in both laboratory and practical models. In laboratory models, treatments of doliolaria with GABA or MSG, at a dose of 10−1 mM for 72 h could induce larval settlement at about 90% and 93%, respectively, compared with the control group (about 20%) (P