1 DECEMBER 1999
Sent: October 29, 1999
From: Norsk Kveite A.S. <n-kveite@online.no>
To: <artemia-l@sparklist.com>
QUESTION 1:
Has anyone done enrichment analysis showing if there are differences
in obtained levels of HUFA (DHA most important) in Artemia from Great Salt Lake compared with Artemia from Russian sources (RH/Eurasian Artemia). Specially the levels around 24 to 30 hours of enrichment are interesting since this is our present enrichment time for GSL cysts.
Olav J. Lyngstad
Norsk Kveite A.S.
Eikevaag
N-5314 Kjerrgarden
Norway
Tel /Fax: (+47) 56 14 52 05
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COMMENTS 1:
Generally we obtain lower enrichment levels using RH instead of GSL. We talk about a delay of 3-6 hours maximum. This implies that if you want to reach the same enrichment levels as with GSL, it's necessary to enrich another 3-6 hours.
However, in our studies on the DHA metabolism of Artemia we saw that RH cysts retain DHA much longer than GSL. Losses in DHA were approximately 20% for GSL after starvation (3 hours). In that same starvation period of 3 hours DHA losses were only 3% for RH. When the starvation period was prolonged to 6 hours the losses were 30% and 4% for GSL and RH respectively. Also the hatching synchrony in
RH is much better than for GSL;. this gives a more homogenous hatching and enrichment.
Philippe Dhert
E-mail : philippe.dhert@rug.ac.be
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QUESTION 2 :
Getting ready for another season of production (COD, Yellowtail
flounder, Halibut) and would like some reliable information on the
quality of Artemia cysts. Can somebody please explain the differences
between GSL and non-GSL cysts and what would be the better type to feed marine larval fish? Looking at enrichment uptake and reductions in HUFA levels during starvation periods; any advice on where to order these cysts and hatching rates would be appreciated.
Nicole Saunders
Ocean Sciences Centre
Logy Bay, NF, Canada
E-mail: nsaunder@morgan.ucs.mun.ca
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COMMENTS 1:
Cysts most often used in larviculture of marine species for starting them off are the high HUFA small cyst varieties such as Vietnam, Brazil, Peru.....These are a bit pricey but aren't all the cysts nowadays?
As soon as the larval fishes' mouth opening is great enough they are switched to either GSL or CIS product that are enriched with emulsified oil (such as our SELCO's). The price of GSL will be greater than the CIS products but normally will have a higher HUFA profile.
Howard W. Newman
Inve Aquaculture, Inc
Artemia task-force div.
E-mail: Bshrimp@aol.com
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COMMENTS 2:
From what I've been told, one of the principal problems with GSL cysts is that there aren't any, right now. Before we all get into a panic, though, altogether there must be loads of experience with other currently-available cyst sources among the subscribers to this list. Does anyone feel like sharing it?
As for myself, I've nearly always dealt with GSL cysts from one supplier or another over the past 15 years, for growing temperate marine fish, except for a recent "flirt" with an alternative which is only referred to mysteriously as "RH" and marketed exclusively by INVE. (The result was very positive, but I have also been told by INVE this year that quality from this source is not what it was 18 months ago.)
I - and I suppose many others, too - would like to read comments from users of any other good-quality cysts which are on the market.
Tony Broadhurst
E-mail: KARENB@santandersupernet.com
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COMMENTS 3 :
RH is just an internal cyst designator at INVE that stood for REMOTE
HARVEST.
CIS or NIS was the collective abbreviation for the countries that
withdrew from the Soviet Union (Russia now) and stood for Commonwealth of Indepenent States and Newly Independent States. Both abbrev. were used.
I think that the RH/CIS source of INVE cysts is more accurately that the QUANTITY so far this harvest season is not as great as last year but the QUALITY has not changed that much. The weather patterns around the planet have been very different again this year making the harvest season delayed.....ie. the weather has been too warm even well into November.
Cysts in general will be expensive and in short supply. Alternative
feeding strategies will be needed in order to mitigate this shortage.
Howard W. Newman
Inve Aquaculture, Inc
Artemia task-force div.
E-mail: Bshrimp@aol.com