So I have some rat pups that are now the proper size for euthanizing for a couple snakes. I was told before that pink mice and rats are resistant to asphyxiation, and that they will actually die faster and more humanely if put directly into the freezer. I have not done this yet, because while it certainly takes a heck of a long time for live pinks to suffocate compared to an adult, and this seems to be true, I didn't want to be wrong and be inhumane.

So.. questions... is it better to freeze newborn rat pups, or use the C02 chamber? How about as they get older? IF freezing is better for newborns, at what age does C02 become more effective/humane (disregard if freezing is a no-no)?

I do have a C02 chamber that has worked nicely for weanling pups up to adults, but I haven't had to use it on anything younger until now.

Thanks for the help guys.