CLOSING THE REPRODUCTION CYCLE OF SHRIMP
From: Patrick Wood patjwood@hotmail.com
To: shrimp@egroups.com
Sent: 20 September 2000
QUESTION:
Has anyone else read the article yet by Reid Hole of Nutreco (salmon aquaculture and feed company) in September's Fish Farming International where he says about shrimp 'the reproduction cycle is not closed'. Surely this is not true.....?
Patrick Wood
E-mail: patjwood@hotmail.com
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COMMENTS 1 :
I have not read the article, but it certainly is not true for P. vannamei. Though wild seed are still in use, the cycle has been closed by many companies and I believe will tighten even more as the advantages of closed cycle animals become economically apparent.
Stephen G. Newman Ph.D.
E-mail: sgnewm@aqua-in-tech.com
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COMMENTS 2 :
With P. indicus, here in South Africa, we use both pond-reared broodstock and wild broodstock. Wild broodstock give more nauplii per female (100,000 to 150,000/spawn) initially, but this soon drops to about double (50,000 - 60,000) the domestic stock (25,000 - 50,000). In our context, until such time as we can get the same nauplii from domestic broodstock, I would consider the cycle as not fully closed, but 80% there.
Laurence Evans
E-mail: laurence@amatikulu.co.za
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COMMENTS 3 :
I did not read the article, but I believe it can be considered that the cycle is closed for a wide range of Penaeid species. In New Caledonia and in Tahiti, IFREMER closed the cycle of a few species years ago, and more than 25 generations of Litopenaeus stylirostris (in particular) have been reared since then. A small (but growing) industry is born in New Caledonia based on this "closed cycle" strain, which is all the more resistant to IHHNV. These captive "closed-cycle strains" allowed us to control the sanitary status, and to conduct genetic selection.
Cyrille Goarant
IFREMER
BP 20259 Noumea
New Caledonia
E-mail: cgoarant@ifremer.fr
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COMMENTS 4 :
How do the P. stylirostris in NC compare to the SuperShrimp stylirostris from Mexico? Did your strain come originally from Mexico? I remember helping source and send from Mexico wild postlarva stylirostris to Aquacop in Tahiti in 1988. Is there still the occasional need for wild broodstock?
Patrick Wood
E-mail: patjwood@hotmail.com
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COMMENTS 5 :
Not true for P. monodon either. We have 4 generations here in Thailand at the moment although it is true to say that the spawning efficiency is not the same as wild broodstock. Having said that it is getting better all the time.
As Cyrille mentioned, several penaeids were kept in closed reproduction in Tahiti and New Caledonia many moons ago, including P. monodon. The P. monodon cycle has also been closed in the Philippines and earlier in Thailand by Piamsak Menasveta's group at Chulalongkorn University.
I suspect Reid was referring to commercial availability and forgot about the Penaeus vannamei and stylirostris.
Dan Fegan
E-mail: fegan@loxinfo.co.th
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