Date: 06 June 1998
From: Stephan Pflume <spflume@gwdg.de>
To: BRINE-L@UGA.CC.UGA.EDU
QUESTION:
In an ancient thread Howard W. Newman mentioned the naturel food of Artemia: Dunaliella, Tetraselmis or Isochrysis spp..
As I read Dunaliella is the main food and brings the red color to the
shrimps. As a question of time and space I do not run Artemia
cultures every year. Therefore I would like to know whether Dunaliella is able to survive longer dry periods. As Artemia's natural habitats tends to dry out, its food should survive these periods, but I am unsure.
Here in Goettingen, Germany exists a Algae Collection which provides a great amount of living algae species and I'm assuming they also have Dunaliella.
Is it worth to start cultures of e.g. Dunaliella salina?
Stephan Pflume
Abt. Vegetationskunde und Populationsbiologie
Wihlelm-Weber-Str 2.
37075 Goettingen
Germany
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COMMENTS 1:
Dunaliella is a green motile algae that is halotolerant or more aptly,
halophilic (salt loving). In years past it was the dominant species making up the primary productivity of the Great Salt Lake in Utah.
Dunaliella, which was the primary productivity here at the Great Salt Lake in Utah, is a preferred diet of Artemia. Salinity in the Artemia environment below about 175-180 ppt the Dunaliella cells are green, above this salinity they turn red, up to saturation (above 264 ppt). It is normally the oxygen transport mechanism that makes the Artemia turn red. The Dunaliella survives quite well in moist environments and is harvested regularly in hypersaline ponds and lakes for beta carotene extraction.
Howard W. Newman <BShrimp@aol.com>
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COMMENTS 2:
A fairly comprehensive guide to sources of microalgae cultures can be found at:
http://www.aquariumfrontiers.com/1998/april/features/1/default.asp
There are a large number of links to major collections that have web
sites towards the end of the article.
In general, Carolina Biological is the cheapest source, but the culture
information that they give is much less complete than places like UTEX and CCAP.
The culture information is quite helpful. For example, in the UTEX
collection, the following species/strains of Dunaliella are listed that
are cultured in higher than seawater salinity media:
LB 2192 Dunaliella peircei Nicolai: 2x seawater, source, Lake Marina, CA, USA
LB 200 Dunaliella salina (Dunal) Teod.: " " salt lake; Russia
LB 1644 Dunaliella salina (Dunal) Teod: " " Baja California,
this strain grows at up to 15% NaCl
L 1644 Dunaliella salina (Dunal) Teod.: axenic from above,
cultured in AS100, "similar to" artificial seawater with 100 g/L
NaCl added.
Craig Bingman <cbingman@netcom.com>
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COMMENTS 3:
Is there a new spp. now in the Great Salt Lake or has the system crashed?
Jouni Jaakkola <Jouni.Jaakkola@mame.pp.fi>
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COMMENTS 4:
I believe that the lower salinity has favored the pennate and centric
diatoms. The Dunaliella that appears in the initial winter bloom is quickly grazed by the Artemia and the pennate diatoms are too large for the nauplii and juveniles....therefore a lot of them starve when the Dunaliella is gone.
Salinity is the issue.
Howard W. Newman <BShrimp@aol.com>
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COMMENTS 5:
I was misled by two thinks: beta carotene causes many crusters to
turn red. Animals do not produce carotenes, but algae and plants
do. Also yeast does not contain carotenes, so Artemia or other
branchipods grown under laboratory conditions only feeded by yeast
will lack red colours.
Elsewhere I read about red saline water, caused by Dunaliella.
So I came to the conclusion Dunaliella must be rich in carotenes and
cause therefore red Artemia.
My observation is right that higher salinity leads to more reddish
Artemia?
I thought the GSL occasionally dries out, doesn't it?
Stephan Pflume
Abt. Vegetationskunde und Populationsbiologie
Wihlelm-Weber-Str 2.
37075 Goettingen
e-mail: spflume@gwdg.de
***************
COMMENTS 6:
I believe that it is generally accepted that the GSL went dry about 3000 years ago. The GSL is divided into two arms that are separated by a rock filled causeway for trains to cross the lake. When the causeway was first built it was a semipermeable structure that allowed mixing through the rock fill.
However since 1984 when the lake level came up 12 feet, there was so much fill dumped on the causeway to raise it that it has essentially sealed it. The north arm today is 260 ppt while the south arm is 85 ppt. The north arm is red with halophilic bacteria and some Dunaliella.
Howard W. Newman <BShrimp@aol.com>