How has it been domesticated for the past 8,000 years? One can surely distinguish between the methods used now and the methods used in the past. What matters is not the moment of death, but the entire lifetime beforehand, and in the past, chickens, turkeys, etc. had reasonable lives before slaughter. Now, in the age of factory farming, where the animal has become nothing but a cost-sensitive commodity, by and large, they do not. Nor do cattle or other livestock, by and large. This fact is what is either not being grasped, or being purposely ignored in most of these reviews.