step by step guide to making a c02 gas chamber

[hermanlover]

Originally Posted by DraigGochHerp

Why is silicone lubricant not suitable? It doesn't com into contact with the mice.
Graham.

it is pushed through by the gas, and silicone is toxic so i would rather not risk it really. better to be safe than sorry

Originally Posted by Skyespirit86

I have to admit- I don't reckon that is true, although I wish it was. All the mice I have ever brought are bloody-nosed indicating they have been bashed, quite hard in some cases.

as has already been said, it can be down to too much c02 and the damage to blood vessels when frozen and thawed, they have a lot of blood vessels in the nose, which are all close to the surface, so they arent hard to damage.

Originally Posted by dragonsRus

After Buying all that and replacing the Co2 at 11 quid a time, its cheaper to buy frozen from a shop

you would be surprised really, theres a hell of a lot of gas in that cylinder, and there are bigger cheaper cylinders aswell.

Originally Posted by Sam'n'Droo

I wasn't sure about the extra tube on the lid either. If C02 is heavy as everyone says it is then the air will get pushed to the top of the chamber regardless of whether there is a tube there or just a vent hole.

Good simple design though. Off to halfords now.

Drew

yes, but the tube lets the air out, you then place it in water and no air can go back in. at the start there wont be a high flow of co2 in, or done correctly there shouldnt be, so you will get backflow of air, which will slow the process down, and make it harder to control.


thanks for the links to the gas cylinders etc, will have a try with them soon

cheers
lee

[SnakingSprout]

I may just be ebing stupid here but surely just putting the mice in an encosed environment for a suspended period of time would commit the same function. Simple respiration process?

[Ssthisto]

It wouldn't happen fast enough to be humane. There are critical concentrations at which the rats/mice lose consciousness - and leaving them in an enclosed box doesn't hit that concentration fast enough.

[SnakingSprout]

Okay, fair enough.

Just out of interest how long would you expect it to take?

[Ssthisto]

If you're getting it right with your concentrations (replacing 20% of the atmosphere in the container per minute) it should take five to ten minutes to fully euthanise an adult rodent, although leaving them for half an hour in the container if you can is a good idea to ensure they absolutely won't wake up when you take them out.

[utterbeastage]

Originally Posted by Ssthisto

If you're getting it right with your concentrations (replacing 20% of the atmosphere in the container per minute) it should take five to ten minutes to fully euthanise an adult rodent, although leaving them for half an hour in the container if you can is a good idea to ensure they absolutely won't wake up when you take them out.

christ , imagine you bought helium by accident

[genghis55]

would it be better 2 have a small container, cuz if the are more rats in a small space it would be quicker right?

[Ssthisto]

Crowd too many rats into a small space and it's going to scare them and upset them because they're overcrowded.

[Issa]

Originally Posted by Ssthisto

If you're getting it right with your concentrations (replacing 20% of the atmosphere in the container per minute) it should take five to ten minutes to fully euthanise an adult rodent, although leaving them for half an hour in the container if you can is a good idea to ensure they absolutely won't wake up when you take them out.

5 - 10 mins?? Isn't the idea of humane euthanasia a FAST painless death? I know the way I cull is a bit more hands on (Cervical Dislocation or the "Pencil Method") but at least I can say all of mine are dead within 30 secs, start to finish.

[Ssthisto]

If most of that five to ten minutes is unconscious and anaesthetised, then yes, it's a painless death even if it's not the fastest.

I do agree that cervical dislocation is fast and humane if done RIGHT - but I don't fancy the learning curve.