BIOCHEMICAL-COMPOSITION OF NYCTIPHANES AUSTRALIS AND ITS POSSIBLE USEAS AN AQUACULTURE FEED SOURCE - LIPIDS, PIGMENTS AND FLUORIDE CONTENT

Nyctiphanes australis contained, on a dry weight basis, an average of 52% crude protein and 5.0 to 9.5% lipid. The fatty acid profile of N. australis was markedly unsaturated, with a mean total omega 3 fatty ac id content of 48.6+/-2.4% of total fatty acids. N. australis contained high levels of the essential long-chain polyunsaturated fatty acids e icosapentaenoic (EPA, 20:5 omega 3) and docosahexaenoic (DHA, 22:6 ome ga 3), ranging from 16.6 to 36.5% and 11.1 to 24.8%, respectively. The concentration of total carotenoids ranged from 137 to 302 mu g g(-1) dry wt, with no significant differences in concentrations found with s eason or life stage. The carotenoids were comprised of 79.5% astaxanth in and 20.5% canthaxanthin. The lipid and pigment compositions of N. a ustralis suggest that the species could serve as a suitable feed sourc e for cultured salmonids. Like other euphausiids, N. australis contain ed high levels of fluoride, with a seasonal range between 277 and 3507 mu g g(-1) dry wt. The high fluoride levels found in N. australis wou ld not detract from its potential as a feed source for salmonids becau se ingested fluoride is largely absorbed by the skeleton.