Secret footage has appeared of halal slaughter in a local Islamic abattoir here. Besides, how can an animal bleed to death, drained of all it's blood unless the heart pumps it out! For that to happen, the animal is conscious until it's last moment.
That requires it to be alive, not to be conscious. Most ways of sedation wouldn't be a good idea because the chemical would be left behind in the meat but there's one way that won't--hypoxia. A zero-oxygen environment would be lethal and thus unsuitable but if you use a low oxygen environment you can cause unconsciousness without death. (You're risking brain damage but that's irrelevant as the animal won't survive anyway.)
Nope. Brain death is not necessarily an obstacle to continued beating of a heart. A heart doesn't even need to be connected to a brain, or to be connected to a body, in order to keep beating for hours.
Only using the (biologically unsound, and logically circular) idea of death wherein cessation of heartbeat is death by definition, can you claim that it is necessary for an animal to be alive for its heart to beat.
Brain death need not stop the heart (it might; but it needn't). As any transplant surgeon can attest.
If you kill it with a lack of oxygen won't you also stop the heart?