Artemia prey size and mode of presentation: Effects on the survival and growth of phyllosoma larvae of southern rock lobster (Jasus edwardsii)

Performance of phyllosoma of the southern rock lobster (Jasus edwardsii) was examined after feeding Artemia-based diets. Survival and growth of newly-hatched larvae cultured to Stage III were lower (p < 0.05) when fed 0.8 mm Artemia than 1.5 mm or 2.5 mm Artemia alone or 1.5 mm Artemia in combination with pieces of mussel (Mytilus edulis planulatus) gonad. This could not be altributed to deficiencies in the composition of fatty acids but appeared to be due to the inability of larvae to capture sufficient appropriate-sized, enriched Artemia for their nutritional requirements. There was an indication that survival and growth were higher between Stages III and V when fed 2.5 mm Artemia than 1.5 mm Artemia alone or in combination with mussel pieces. However, Stage VI larvae grew to a similar size at Stage VIII when fed 1.5 mm or 2.5 mm Artemia. Unexpectedly, larvae fed the combination of 1.5 mm Artemia plus mussel supplement had lower survival than found previously, and generally lower than when fed ≥ 1.5 mm Artemia alone. This was despite an apparent nutritional profile (lipid content and fatty acid composition) of mussel more akin to that of newly-hatched phyllosoma than enriched Artemia. On the other hand, survival and growth to Stage VIII were higher when larvae were fed alginate pellets containing Artemia than when fed 1.5 mm or 2.5 mm Artemia alone.