They don't live in their "head" like we do but their brain extends through the spine do when the head comes off they have very coordinated leg and wrong movements for a long time and lots of nerve energy firing showing not residual energy but active torment and confusion even with one bird living for 15 days with no head being fed through the neck. Of you want guilt free raise your own and when study veterinary assistance. Get a vets IV and an respirator with tank with air from swimming supply and a tank with co2 from a welding supply and keep the chicken awake as long as you can. When you can't keep it awake sit it in your lap peeing it to calm it until it goes to sleep open up the co2 in a small room with an attendant checking on you, put the IV in and let the blood run out. The bird will pass out and die peacefully without pain the meat will have very little blood if any especially if you slowly pump the blood when it stops flowing. You can omit the low oxygen but it may suffer.
You will get fresh live chicken
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