Effects of starvation and feeding on the fatty acid profiles of Stage I phyllosoma of the spiny lobster, Jasus edwardsii

Fatty acid analyses were conducted on newly hatched and 8-day-old-starved and fed Stage I phyllosoma larvae of the spiny lobster, Jasus edwardsii. Fed animals were offered excess 1.5 mm juvenile Artemia (enriched using the alga Isochrysis galbana, Tahitian isolate, T. iso.). After 8 days, there were significant increases in larval dry weight and the proportion of lipid in fed phyllosoma, whereas these parameters decreased in starved phyllosoma. The abundance of the saturated fatty acids 16:0 and 18:0 increased in both starved and fed phyllosoma, whereas the main monounsaturated fatty acids 16:1n-7, 18:1n-9 and 18:1n-7 increased with feeding but decreased with starvation. There were no significant differences in the relative proportions of the highly unsaturated fatty acids (HUFAs) arachidonic (AA, 20:4n-6), eicosapentaenoic (EPA, 20:5n-3) and docosahexanoic (DHA, 22:6n-3) acids between newly hatched and starved animals, whereas quantitatively DHA decreased with starvation and feeding. The DHA/EPA ratio was significantly lower in the starved and fed phyllosoma (0.5) compared with that found in the newly hatched phyllosoma (0.9). The lipid profiles of the newly hatched, starved and fed phyllosoma contained large amounts of n-6 fatty acids resulting in low n-3:n-6 ratios (2.8, 2.7 and 1.6 respectively). The importance of these results and the ability of enriched Artemia to provide a suitable fatty acid profile for this species are discussed.