CO2 Chamber

[joeysgreen]

lol, I was thinking that it has death written all over it as well. It's the mouse holocost. Bad joke, sorry.

Buying a CO2 cylinder from a gas supply company is the way to go for the long term. It allows convenience, consistancy, and reliability.

Since on the topic, I"ll recall a few points from the CCAC guidelines and experience working in an animal care facility in regards to gas chambers.

1. They shouldn't be over- crowded; and definately emptied of carcasses prior to admitting the next batch to be culled.
2. Euthanasia should not occur in the same room or in view of other animals.
3. Chamber can be preloaded with CO2, or the gas can be added after the animals. If added after, it should be slowly ramped up to avoid stressing the animals with a strong jet of air.
4. Ventilation. This isn't an overly toxic gas, but it is heavier than room air. If in the basement for example, you'll want plenty of opportunity for diffusion. In the lab there was always an air current from clean, to maintainence rooms, to outside. This won't be the case in the average household, but something that should be considered. A simple bathroom exhaust fan should suffice.

[RICHARD25]

Originally Posted by joeysgreen

lol, I was thinking that it has death written all over it as well. It's the mouse holocost. Bad joke, sorry.

Buying a CO2 cylinder from a gas supply company is the way to go for the long term. It allows convenience, consistancy, and reliability.

Since on the topic, I"ll recall a few points from the CCAC guidelines and experience working in an animal care facility in regards to gas chambers.

1. They shouldn't be over- crowded; and definately emptied of carcasses prior to admitting the next batch to be culled.
2. Euthanasia should not occur in the same room or in view of other animals.
3. Chamber can be preloaded with CO2, or the gas can be added after the animals. If added after, it should be slowly ramped up to avoid stressing the animals with a strong jet of air.
4. Ventilation. This isn't an overly toxic gas, but it is heavier than room air. If in the basement for example, you'll want plenty of opportunity for diffusion. In the lab there was always an air current from clean, to maintainence rooms, to outside. This won't be the case in the average household, but something that should be considered. A simple bathroom exhaust fan should suffice.

I think a regulator would be a necessity as well, thanks for the tips!

[lovemyballs]

hey guys i work in a welding supply store and you can buy a tank of co2 for $275 full of c02 after the first initial purchase it will cost around $30 to swap it out for a full one. i would imagine you could off thousands of feeders off one tank. you could also set up a account and go the lease/rent route for $60-$70 a year plus the cost of fills but its way cheaper to go the buying out right route when looking at the big picture.

[joeysgreen]

is that a 200lb tank? Usually about a 15 or 20lb tank suffices.
I think a regulator is a good idea; they cost around $80 last time I checked. On larger tanks, I think it's a mandatory thing.

[lovemyballs]

every company has their own terms of sizing them but we go by how many liters if water it would hold so the tank i was talking about is a size 15. it would weight maybe 30pounds. i really dont see any need for a regulator, you could just use the valve to regulate the amount of c02 coming out. regulators are for precision and in this case i think a regulator is pointless.

[joeysgreen]

In my use, the regulator was to set a maximum limit to the stream of gas exiting the cylinder. The tank may have 2500psi withen, but we'd have it set so only 50psi reached our anesthetic machine. With such a small cylinder a regulator is probably pointless; I know many people don't use one.

Ian

[Mads]

You will need some way of regulating the rate at which it enters the chamber. You can't manually open it such a small amount, so all you would end up getting is a very quick blast of CO2. You can get many types of regulators and you don't need anything very fancy. Like Ian said, you just need to slow the flow down to a very small amount. I think I ran mine at 10-12 psi. If you go much faster then that it makes an awful racket and all the mice panic. At a flow rate of 10-12 psi it makes a small hiss, but they don't really feel the flow and as such don't seem to panic. It's the airflow that freaks them out.

Also, make sure that you put the CO2 right down at the same level as the mice. If you pump it in from the top it will take a while for it to reach the mice. CO2 has pretty much the same density as atmospheric air, and thus won't really sink or rise.

We used a 50 pound container and we were replacing it every 4-6 weeks. At that time we were freezing and packaging 20 000 mice per month. So, a small container would last the average person a very long time.

Mads

[joeysgreen]

Mad's, how did you euthanitize the pinkies?