Having to put an animal down is never a pleasant situation. But unfortunately, there are circumstances when a livestock famer faces that, e.g. when an animal is sick. Many methods of killing animals are painful. And that makes stunning necessary, to cut off the animal's awareness and sensitivity to pain at the time of killing. Captive bolt guns are especially designed for stunning animals. The pressure wave from the bolt ensures that the animal loses consciousness. After stunning, you can kill the animal through bleeding.
To achieve that, you use a knife to make a cut across the throat, penetrating to the neck tissue and cutting through the carotid arteries.
