Feeding the lined seahorse Hippocampus erectus with frozen amphipods

Amphipods are a natural and alternative feed in aquaculture but their potential use is limited by lack of knowledge of feeding regimes. The present study provides a feeding regime of frozen amphipods (Elasmopus pectenicrus) for the lined seahorse Hippocampus erectus, the second most traded species worldwide. Ingestion rates of amphipods were measured to establish the optimal amphipod size, duration of feeding and feed ration. Use of large amphipods (8.7 ± 1.1 mm total length) increased the total ingested biomass in fish of 60-110 mm standard length, compared to medium and small amphipods, in accordance with previously suggested relative sizes. The highest feeding activity occurred during the first 12 min. Fish ingested 4.5 ± 2.3% their wet weight, which is similar to the feed ration previously proposed for other seahorse species. The present study supports the potential of amphipods as a feed in aquaculture and will aid their use in culture protocols.