ARTEMIA ENRICHMENT PRODUCTS

QUESTION :

I’m looking for Artemia enrichment products. We have problems with our current enrichment procedure, using ALGAMAC-2000, particularly in DHA. If anyone knows of a better product, or a successful procedure (12 hours in 25°C at 400 g/mł), we will appreciate it.

Yoram Hoffman
Ardag ltd
Eilat
Israel

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COMMENTS 1:

It seems as though you may not be enriching for a long enough time period.  We have used the 2000 and had to enrich for up to 16 hours to see an uptake in DHA.  Right now, we are using Algamac 3000 and DC-DHA Selco on alternative days for 16 hours and get sufficient DHA levels in the Artemia.

Lori Thorne, Research Technician
Ocean Sciences Centre, Aquaculture Facility
Memorial University
St. John's, NF
737-3253(W) 737-3220(Fax)
437-6548(H)

E-mail: l_thorne@lycos.com

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COMMENTS 2 :

We have always decapsulated our Artemia using a mixture of bleach, NaOH, and filtered sea water.  The cysts are first hydrated in fresh or salt water for 1 - 2 hours with aeration.  They are then concentrated into a mesh bag (~80 µm) and are then placed in the decap. mixture along with aeration for a period of time until the temperature reaches 25°C and no higher (cysts will burn).  The process is complete when the temperature reaches this max. and the cysts have turned very orange in colour. They are then quickly rinsed with icy cold water for 10 - 15 min until there is no odour present (decap mixture odour).
This procedure works very well with GSL cysts but is slightly different when using Russian cysts. 

Lori Thorne

E-mail: l_thorne@lycos.com

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COMMENTS 3 :

We feed Artemia to shad fry for a few days, then release them into selected rivers as part of a state sponsored shad restoration project. We have good success in hatching premium GSB cysts in one pound batches and have developed our own method for achieving excellent separation. For all the obvious reasons, decapsulation should improve the food value/quality of the lower quality/price cysts. We have completed a series of hatching trials using decapsulated cysts over the last two seasons. We can produce a nice orange decapsulated cyst. We are conscious of the temperature factor. We decapsulate with a Clorox [Jarvex?] solution and rinse well with a sodium thiosulfate solution. After decapsulation, high quality cysts always produce a higher degree of hatch than low quality, but neither exhibit as high a degree of hatch as when both are hatched using "normal" non-decapsulating methods. Have you ever tested the decapsulated cysts against regular cysts in hatching trials? If so, I would be interested in hearing about your results. Unhatched decapsulated cysts tend to settle out in our main Artemia holding tank as well as in the fry culture tanks when they are added as a food item. Shad fry feed on suspended particles. Because the decapsulated cysts settle rapidly to the bottom of the fry culture tanks they are wasted and become a substrate for fungal growth. Do you have any experience with this particular situation? Have you tried any of the Artemia substitutes? How did they work? 

Sam Chapman
Aquaculture Specialist
Tel: 1-207-832-7548 [home]

E-mail: samchap@ime.net

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COMMENTS 4 :

I'm interested to know what precautions you take for decapsulating Russian cysts. Our supplier has advised against trying to decapsulate these cysts, and with the recent price of cysts I've been sufficiently discouraged to try it.

Scott Lindell
Scientific Director
Fins Technology
Tel: 413/863-8905 x104
fax 413/863-3575
email: slindell@finstechnology.com

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COMMENTS 5:

I have never tested decapsulated cysts against undecapsulated cysts for hatching success, but I would imagine that if properly decapped, the decapped cysts would hatch much quicker and be cleaner than the other cysts.
  The unhatched decapped cysts that you speak of that are sinking to the bottom of your fry tanks are either burned dead cysts or egg shells.  In order to get rid of egg shells, you should wash the hatched Artemia really well and decant off the good nauplii and separate the detritus (shells and unhatched cysts).
  Also, try not to overfeed your tanks. This can also make the tanks dirty as uneaten Artemia will die and settle on the tank bottoms. Feed only on demand - small amounts frequently.

Lori Thorne

E-mail: l_thorne@lycos.com

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COMMENTS 6:

We have just switched over from using Prime "gold" grade cysts to using INVE EG grade cysts, and suspect significant less upstake of enrichment by the Artemia.
- we draw this conclusion by the excess enrichment still in solution at the end of the enrichment period, much more so than we experienced with the Prime cysts.
Common practice is:  Time 0 - incubate cysts
24 hours - first enrichment 0.3 g/L    A1 DHA selco
34 hours - 2nd enrichment 0.3 mg/L A1 DHA selco
48-54 h   - harvest feeds
cysts are incubated at 28°C, however during the first night,  temp can fall below 25°C, and then remain between 25.5 - 26.5°C during the subsequent days.
I know temperature should be kept constant at 28°C for optimum hatching/enriching, however the excess enrichment was not encountered with Prime cysts.

Rachelle Hawkins
Seahorse Australia

E-mail: carhawkins@telstra.easymail.com.au

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COMMENTS 7 :

Most probably the EG cysts you obtained are parthenogenetic strains that just do not enrich as fast as the GSL strain that you were getting from PRIME ARTEMIA. Does your EG tin/pail say “product of CIS”??? Certainly they will enrich faster (even EG) if you maintain 28-30°C as the 25°C level will slow uptake. I think that Philippe Dhert of Artemia Reference Center did an enrichment uptake study on the two or more strains as compared to GSL and will hopefully provide the kinetics of this activity.

Howard W. Newman

Desert Lake Technologies, LLC

E-mail: Bshrimp@aol.com

URL : www.desertlake.com

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COMMENTS 8:

We have found that Artemia nauplii reach an equilibrium where they excrete more or less the same amount of particles that they consume, and often this is achieved just after few hours, sometimes minutes. For example, they got filled with bacteria after just 45 min to 2 h depending on the strain, some antibiotics dissolved in an enrichment solution, after 1-2 h. This suggests that enriching the nauplii for longer periods (lets say more than 24 h for practical terms) not only diminishes the nutritional value of nauplii but could be a waste of resources.

Brune Gomez-Gil, Ph.D.

CIAD/Mazatlán Unit for Aquculture

AP. 711 Mazatlán Sin. 82000

Mexico

Tel: 52-69-880157

Fax: 52-69-880159

E-mail: bruno@victoria.ciad.mx

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