Hey everyone, being new I'm a bit hesitant to come in on such a controversial topic... so I'll just give you some research and my little opinion. This is a study, I guess you would call it, someone on another fish board I have been with for a few months did when we were all on the topic... (not my study, I couldn't do it!)
Euthanasia prelim results (not for the squimish)
there has been loads on the board lately over this and some very wrong info here and there so i decided to do some fairly rougth experiments tho the results should stand as a good starting point for more in depth reaserch.
first the setup and problems faced.
first i tried to decide how you could measure in some way the level of pain a fish is feeling so various methods could be evaluated. after alot of thought i decided the simplist yet most accurate way to do this was to measure different stress level hormones both before and and directly post mortem. the hard part is getting a base reading from the fish, as any form of penetration with a needle will induce stress that will show in the blood 15-20 seconds later and this could skew the results. however if u tranq the fish first then it's an invalid test.
so it was decided to house the fish seperately in small 18"x12"x12" tanks for 48 hours with 70% water change daily with water taken directly from the sterile chamber of a central sump filter. then just before the test on each i sampled there water and tested for the hormones secreted in there urine useing a Gas Photo Spectrometer and Radon Gas Ioniser. this gave good non stress load levels on each subject.
It was decided that rather than just post a long list of data that wouldnt realy mean much to most i would use a scale of 1-10 to describe the humane index of each method if you like with 10 being the most humane.
the subjects chosen were 3" Gold fish all of wich were happy and healthy before hand.
the methods tested were Co2 (will count for all types) Clove oil, MS222, Freezing,Pure Ethanol Bath (98%), Para formaldahyde (cranial injection and submersed bath in 30% solution),Potasium permanganate cranial injection (is of use to me on the very big fish we sometimes have to deal with), spinal cord seperation,decaptation and hard blow to the head.
the following results were acheived
Co2 7
clove oil 7
MS222 9
Freezing 1
Pure Ethanol bath 2
Para Formaldahyde Bath 6
Paraformaldahyde crainial injection 9
Potaasium Cranial injection 9.5
Spinal Cord 3
Decapitaion 4
hard blow to the head (varied results from 10 experiments rageing from 1 to 8 )
ok this isnt conclusive science the experiment has a couple of flaws but the data is valid test data, and would server as a good start for more extensive research by someone with alot more time than me. i wouldnt recomend decapitaion as the results are very varied there it cant be described as a predictable method.
as for the rest that is for others to argue over.
[/COLOR=purple]
As for me, call me spineless if you like, but I just don't have the heart. I think I should let nature take it's course.