Quote Originally Posted by karls-snakes View Post
Let me start by saying I, like most other snake hobbyists do not enjoy killing rats but it is a necessary evil. Some people use c02 or dry ice and what that does is essentially eliminate the oxygen in the enclosure. I use Ziploc bags, I put one small or just weaned rat in the bag and flatten the battle remove most to the air. The rat dies in 2-3 minutes and only moves erratically for 5-10 seconds so I believe the suffering is minimal. He can still breathe but the oxygen is quickly used up and they don't cry as they do when feeding live. Then they are already individually bagged I then weigh them and use a marker to write their weight on the bag. I have not used this on a full grown rat but I imagine you would need a pretty strong bag.
I do the same thing with my pinkies and fuzzies with one important (to me) difference. I have a CO2 tank and I put a puff of CO2 in the bag. If you get the mix right the CO2 acts as an anesthesia. I then evacuate all the air and freeze. I am not going to say that this is the most humane way to euthanize. The big problem is that baby rodents are pretty CO2 resistant and if you get the mix two high it can be painful. I have a CO2 chamber for larger rodents. Its just a high plastic tub with a lid. I put a small hole in the side near the bottom to insert a hose to pump CO2 in. It doesn't need to be air tight, you can let the gas vent out the top. CO2 is slightly heavier than normal air and won't dilute enough to prevent death if you just snap a cover on. I have euthanized a lot of rodents with no issues.