RE: NANFA-L-- cold euthanasia

Peter Unmack (peter.lists-in-)
Thu, 31 Aug 2006 09:56:12 -0500 (CDT)

On Thu, 31 Aug 2006, Nick Zarlinga wrote:

> I was under the impression that CO2 is a humane way to euthanatize since it
> is independent of the amount of O2 available to the specimen, therefore no
> perceived lack of oxygen response.

Doesn't CO2 essentially deprive the organisim of O2? My impression is
that red blood cells would not be able to drive off CO2 if there is a high
concentration of CO2 present, thus reducing available cells for uptake of
O2, thus sufficating the fish? This doesn't imply that the fish suffers
per se, since high CO2 or CO tends to put us to sleep relatively quietly
(that's how I'd put myself down if I had to).

And the bicarb will only raise the pH to 8 at saturation (8.2 when it is
at some point less than saturated). Thus shouldn't be a big issue for
most fishes.

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