Percussive Stunning

The primary objective of captive-bolt stunning is to induce immediate insensibility by administering a severe blow to the skull of the animal. The animal must then remain unconscious until it dies as a result of bleeding or pithing. The term ‘percussive’ describes the principal action of the captive-bolt, i.e. the forcible striking of one solid body against another.

The first percussive instrument specifically designed to stun animals was the pole-axe, a crude implement which relied on the strength and skill of the slaughterman to be effective. The subsequent development of the captive-bolt, at the beginning of the last century, mechanised the stunning operation, making it a more humane procedure. The earliest designs of captive-bolt equipment all involved some form of penetration of the skull, as it was believed that the physical damage to the brain was important. However, it was soon realised that sufficient concussive forces alone would cause insensibility. This led to the development of stunners which deliver a non-penetrative blow to the animal’s head. Today, captive-bolt stunning equipment falls into two broad categories: non-penetrative and penetrative. These will be discussed in detail later.

NOTE: Firearms which discharge free projectiles are also percussive in action. But are used to kill rather than stun.

Next: Physiology of Percussive Stunning