effects of algal addition on stability of fatty acids and some
water-soluble vitamins in juvenile Artemia franciscana
A.I.
Olsen, A. Maeland, R. Waagbø, Y. Olsen-2000
Aquaculture Nutrition, 6(4) : 263-273
Abstract :
A
minor stabilization effect was found for the content of total lipids, total
fatty acids and docosahexaenoic acid (DHA) when Artemia franciscana was
maintained at high concentrations of Isochrysis galbana for 72 h at 12°C,
both in 3- and 4-day-old individuals. The eicosapentaenoic (EPA) level was
only stabilized at higher algal concentrations in the 4-day-old A.
franciscana. In the 3-day-old A. franciscana, the EPA content increased at
all algal concentrations during the first 24 h of post enrichment,
presumably as an effect of DHA catabolism. Apparently, the 4-day-old A.
franciscana metabolized DHA, and other lipids, faster than the 3-day-old A.
franciscana did. During the 72 h incubation with I. galbana, the content of
ascorbic acid (AA) in A. franciscana increased approximately to 1000-1200 µg/g
dry weight (DW) at algal concentrations above 3 mg C/L, close to AA content
of the algae. The vitamin B6 content in A. franciscana decreased
from approximately 20 to 4-11 µg/g DW, with highest loss rates at the
higher algal concentrations. The thiamin content of A. franciscana was
independent of algal concentration and remained at 20-30 µg/g DW. The
nutritional effects of the algal incubation on the 3- and 4-day-old A.
franciscana at algal concentrations which can be used during the cultivation
of Atlantic halibut larvae
(< 2 mg C/L) was insignificant, except for the small enrichment effect of
AA already at 1 mg C/L. Other beneficial effects of the algae should not be
ruled out, like possible effects on the microflora of A. franciscana even at
algal concentrations less than 2 mg C/L.
(SINTEF
Fisheries and Aquaculture, N-7465 Trondheim, Norway, e-mail: Atle.I.Olsen@fish.sintef.no)