RE: NANFA-- Sacrificing or immobilizing fish

Bruce Stallsmith (
Mon, 29 Jul 2002 13:48:01 -0400

>The only anaesthetic registered in North America for use in fisheries
>science is 3-aminobenzoic acid ethyl ester methanesulfate (tricaine or
>MS-222). Although MS-222 is a very effective anaesthesia for several fish
>species, its application in the field is limited because U.S. Food and Drug
>Administration guidelines demand a 21d withdrawal period after exposure to
>MS-222 before fish can be released and enter the food chain. As a

Really? I had no idea that there was an official FDA position on releasing
wild fish with a 21-day delay after MS-222 treatment. We used MS-222 when I
was in graduate school to _mildly_ anesthetize sunfish we seined before we
pulled off scales for aging studies. We'd put them in a bucket of fresh
water to recover for about an hour before release, so that they weren't
obviously groggy. I know that aquaculture operators have very strict
guidelines about a time gap between giving a fish MS-222 and selling the
fish for food.

And as always, thanks for the refs, Jan. The correct dosage of clove oil had
completely slipped my mind...

--Bruce Stallsmith
Huntsville, AL, US of A
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