Free amino acid and protein
content in the planktonic copepod Temora longicornis compared to Artemia
franciscana
S.
Helland, B.F. Terjesen, L. Berg-2003
Aquaculture,
215(1-4): 213-228
Abstract:
Previous studies have indicated that natural
zooplankton, the natural prey organisms of marine fish larvae, is superior
to enriched Artemia spp. nauplii in supporting survival, growth and
normal development of pigmentation and eye migration in Atlantic halibut
larvae. The present study was designed to compare the amino acid dynamics in
copepods harvested from a natural lagoon with that of enriched Artemia
franciscana nauplii. The natural zooplankton in the present study was
dominated by Temora longicornis, but varied in its developmental
stage composition, apparent nutritional quality, amount and availability.
The protein content in natural zooplankton varied from 31% to 54% of dry
mass (DM) compared to 31% in enriched Artemia nauplii. The amount of
free amino acids (FAA) in relation to protein was 14% in enriched Artemia
nauplii and varied between 16% and 27% in zooplankton in two consecutive
seasons. The FAA composition of zooplankton in 1996 was unaffected by stage
and season, and showed a species-specific pattern. In response to
starvation, two patterns in the amino acid dynamics of copepods were found.
The first, exhibited by the major nonessential amino acids (NEAA), showed a
continuous reduction in individual amount, while the second pattern,
exhibited by the minor nonessential amino acids and all the essential FAA,
had an initial increase followed by a reduction. It is suggested that the
protein amount in DHA Selco(TM) (INVE)-enriched Artemia nauplii is too low in
order to maximise the growth potential of some marine fish larvae as cod and
halibut.
(Department of Fisheries and Marine Biology, Bergen
High Technology Centre, University of Bergen, N-5020 , Bergen, , Norway.
Tel.: +47-55-58-44-00; fax: +47-55-58-44-50; email: synnove.helland@ifm.uib.no)