Feeding Southern Rock Lobster, Jasus Edwardsii Hutton, 1875, Phyllosomata in Culture: Recent Progress with Lipid-Enriched Artemia
Nelson, MM and Crear, BJ and Nichols, PD and Ritz, DA, Feeding Southern Rock Lobster, Jasus Edwardsii Hutton, 1875, Phyllosomata in Culture: Recent Progress with Lipid-Enriched Artemia, Journal of Shellfish Research, 22, (1) pp. 225-233. ISSN 0730-8000 (2003) [Refereed Article]
Jasus edwardsii phyllosoma larvae were successfully grown in static culture with antibiotics from newly hatched to stage V with high survival. Feeding phyllosomata on Anemia salina Linnaeus, 1758, enriched with (1) a triacylglycerol (TAG)-rich A1 DHA Selco-Chaetoceros muelleri Lemmermann, 1898, nutrient source or (2) a formulated ethyl ester (EE)-rich nutrient source was compared with the more novel approach of using a formulated mussel powder-polar lipid diet attached to mesh. Individuals showed an increase to stage V in dry mass (0.1-1.5 mg) and total length (2.1-6.1 mm). Survival of Artemia-fed phyllosomata was high (92-98% from stages II-III; 49% mean total survival). Animals fed the mussel powder-polar lipid diet had low molt success, although the presence of faecal trails confirmed they were consuming the diet. Total lipid remained generally constant in Artemia-fed phyllosomata from newly hatched to stage V (155 mg g-1 dry mass); this was notably higher than observed for previous feeding trials. The major lipid class in all phyllosomata samples was polar lipid, followed by sterol, with TAG as a minor component only, and EE not detected. The main fatty acids were 18:1(n-9)c, 18:2(n-6), 16:0, eicosapentaenoic acid [20:5(n-3)], 18:0, 18:1(n-7)c, arachidonic acid [20:4(n-6)], and docosahexaenoic acid [DHA; 22:6(n-3)]. Levels of the essential polyunsaturated fatty acids (PUFA), namely, arachidonic acid, eicosapentaenoic acid and, in particular, DHA, decreased, on both a relative and absolute basis, from newly hatched to stage V, although phyllosomata fed the EE-rich enriched Artemia diet showed higher essential PUFA content together with oil content. This experiment further validates that lipids and fatty acids are important nutritional component in rock lobster larvae and that feeding phyllosomata with lipid-enriched Artemia maintains excellent growth and survival in early stages. Strategies will be needed, however, to either overcome the issue of low DHA, in particular, delivered by Artemia (because of retroconversion), or to supply DHA by alternate means at later stages.