The slaughter process has two stages.
- Stunning – when performed correctly, stunning causes an animal to lose consciousness so the animal can't feel pain. The law states that, with few exceptions, all animals must be stunned before 'sticking' (neck cutting) is carried out.
- Sticking – an animal's neck is cut, using a very sharp knife, to sever the major blood vessels in the neck and chest that supply the brain, ensuring rapid blood loss and then death.
The process of killing is similar to the slaughter process in that the animal is stunned prior to sticking, but the stunning method kills the animal.
Slaughter/killing of large animals
The methods available to stun larger animals include the following:
- Penetrating captive bolt – used on cattle, sheep and some pigs. A gun fires a metal bolt into the brain of the animal, causing them to lose consciousness immediately.
- Electrical – used on sheep, calves and pigs. An electrical current is passed through the animal's brain via a large pair of tongs, causing a temporary loss of consciousness. Some systems also pass the current through the heart, so the animal is not just stunned but also killed.
- Gas stunning/killing – used on pigs and involves the use of gas mixtures. Pigs are exposed to high concentrations of gas (currently carbon dioxide).
After stunning, the animal is shackled by a hind leg and hoisted above the ground while the slaughter person ‘sticks’ the animal.
Slaughtering/killing poultry
Two main methods are used to slaughter/kill poultry.
1. Gas killing
The majority of poultry (chickens, laying hens and turkeys) in the UK are killed using gas. There are a number of different gas-killing systems and different gas mixtures may be used, such as carbon dioxide, or an inert gas such as argon, or a mix of the two. Birds remain in their transport crates and are placed into a gas system, where they're exposed to mixtures of air and gas until dead.
This method avoids the need to handle and 'shackle' conscious birds, so has some welfare advantages. UK law states that animals must be killed, not just stunned, using this method.
2. Electrical stunning
Birds are hung upside down by their legs on metal shackles along a moving conveyor belt. They move along the production line to a water bath that stuns them. When the bird's head touches the water, an electrical circuit between the water bath and shackle is completed, and this stuns the bird.
The conveyor belt then moves the birds to a mechanical neck cutter, which cuts the major blood vessels in the neck. Shackling conscious birds causes stress and pain.
Slaughter without pre-stunning (religious slaughter)
Read more about what we're doing on the issue of religious slaughter.