I got baby chicks a week ago, and one little polish roo hasn't looked well since I got him. His crop was enlarged, he had a prolapsed vent, he was wobbly and unsteady. He wasn't growing like the others, and the rest of the flock was starting to pick on him. Yesterday he looked a little better, and I went to sleep feeling cautiously optimistic. I found him this morning laying in the box looking quite dead. In a panic I scooped him up so the kids wouldn't see, and realized he was 95% dead. I couldn't bring myself to break his neck or decapitate him, I was worried I would do it wrong. So I put him in a sandwich bag with about 3 Tbsp baking soda and maybe 1/4 c hydrogen peroxide, then added a kid sock for him to lay on, and closed the top. I realized after I did it that I didn't think to seal out the air.
He never resisted and his eyes were never open, but he lay there gasping for an hour before he passed on. I thought this should have taken much less time, and I'm worried I gave him a less than humane death because of my inexperience. Was the hydrogen peroxide too old and not potent enough? Should I have sealed out the air? Or was this what I should have expected for it to have taken so long?
Any advice would be appreciated so I am better prepared next time. It was a hard morning, and if it could have been easier, I would like to know how to improve things.