Optimization of Artemia Feed Regimes for Larval Giant Kōkopu (Galaxias argenteus)

Optimizing the initial live feed is critical to success in fish larviculture terms of both larval health and productivity. It also vitally important due significant cost provisioning feeds. Glaxiids are high-value diadromous species found parts Southern Hemisphere, which wild-harvested sold for human consumption their form. In emerging aquaculture galaxiids, makes up a great proportion production cycle therefore factor achieving economic viability production. New Zealand, endemic galaxiid giant kōkopu (Galaxias argenteus) considered suitable aquaculture; however, little known larval-feeding requirements. This study compares growth performance survival larvae over four-week period when fed different proportions first-molt Artemia nauplii (instar-I) enriched, second-molt-onward (instar-II+) durations. The treatment group received greatest Instar-I longest duration had lowest mean wet weight survival, leading total biomass compared other treatments. that only instar-II+ achieved an equally best While partial mixed instar-I same productivity, individual were heavier body length was longer. latter appears offer balance between availability particles optimum size range higher level digestibility given levels highly unsaturated fatty acids polyunsaturated acids.