Sorry, in regards to my comment for drawing a line, that was not directed to you personally. I used "you" in reference to every person.
Keep in mind, I am referring to specific extraordinary circumstances. I feed exclusively carbon dioxide euthanized prey, but if I were ever in a position where it came down to feeding live or watching my pet starve to death, I think I would resort to using a live prey item. I would use a live rodent, although probably a younger one yet to open its eyes and thus, as far as I can tell, less aware of its impending death. If it did come down to using an adult rodent though, I still think I would.
Now, I think everyone draws some sort of subjective line as to what animals they will use as live prey. As Samba mentioned, insects are acceptable. There are people out there who believe no living thing should die at all, and would find feeding live insects unacceptable. After all, a lot of people are against boiling lobsters, as they feel that is inhumane. Then, there are people who would have no problem with using live fish as prey, whereas othes would. The same goes for amphibians, reptiles, birds, and mammals (although it may fall somewhere within one of those animal groups). I am certain that somewhere there is someone extreme enough who would even use humans to feed their pets if they could get away with it (After all, there are all kinds of people on this earth).
Also, I should probably note that there is probably a line where people have no problem with feeding live at all, and another where they will only feed live under extraordinary circumstances.
I personally will feed everything up to and including fish as live, with no problem whatsoever. Amphibians, reptiles, and some birds and mammals I will use as live prey in extraordinary circumstances, but avoid as much as possible. Now, all this is entirely based on what I personally feel is the capacity for suffering to be. Even crickets will struggle to escape once captured in the jaws of a lizard.
Anyway, that's just where I stand. I will use any animal that is humanely euthanized as food. I will use some animals and not others as live prey in extraordinary circumstances, and I will use some animals live under any circumstances while not others. This is based on the objective reasoning that some animals have a greater capacity for suffering than others, and a somewhat subjective determination as to which animals are acceptable while others are not.
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