The killing of animals is animal euthanasia (for pain relief), animal sacrifice (for a deity), animal slaughter (for food), hunting (for food, for sport, for fur and other animal products, etc.), blood sports, roadkill (by accident) or self-defense.
Source: Wikipedia
2. Regulatory laws for animal welfare do little or nothing to establish or protect the interests of animals. Animal welfare is the view that it is morally acceptable, at least under some circumstances, to kill animals or subject them to suffering as long as precautions are taken to ensure that the animal is treated as "humanely" as possible.
3. Merely discussing the idea that animals have the same life force and will to live as humans is by most people understood as a personal attack on one's carnivorous eating habits.