My FIL kills his own sheep on the farm and he knocks them on the head, then ties them up upside down then cuts their neck so the blood drains WHILST the animal is still alive. Occ they come to a bit whilst that happens.
That was the practice he was taught as blood left in meat taints it and therefore it spoils quicker. Now he has been doing this for years and when I told him that this practice was almost halal he got all upset.
In my experience here and OS this way of killing animals is the norm.