Cervical dislocation and decapitation (manual and mechanical)

Cervical dislocation (pulling the neck to sever the spine) causes death from cerebral anoxia (interruption of the supply of oxygen to the brain) due to the cessation of breathing and/or blood supply to the brain though haemorrhages from damaged blood vessels in the neck. If there are only a small number of birds to be killed (i.e. up to 70 a day to prevent operator fatigue), and other methods of killing are not available, conscious birds can be killed using cervical dislocation but this is not recommended. The HSA strongly advise this method only for killing stunned birds. Birds should be monitored continuously until death to ensure the absence of brainstem reflexes. The killing of birds can be performed either manually (using own hands) if birds weigh less than 3 kg, or mechanically (assistance from a device) if birds are between 3 and 5 kg. The neck should never be crushed using equipment such as pliers as this does not provide a fast and humane death. Performing this method effectively and consistently requires strength and skill, so team members should be rested regularly to prevent fatigue. As this method does not guarantee immediate insensibility, it should be used in conjunction with a stunning method such as electrical stunning. As with the use of the non-penetrative captive-bolt, an effective kill will most likely result in involuntary wing flapping. For further information on cervical dislocation see the Practical Slaughter of Poultry on-line guide http://www.hsa.org.uk/introduction-1/introduction-3

Manual cervical dislocation

For adult chickens, hold the bird’s legs (and the wing tips if possible) in one hand, close to your hip with the underside of the bird's body against your thigh. Using the first two fingers of your other hand, grip the head immediately behind the skull with your thumb under the beak. Stretch the neck downwards, at the same time pressing your knuckles into the neck vertebrae and pulling the bird’s head back. Neck dislocation should be achieved in one, swift pull.

Killing cone

The killing cone consists of a restraining cone with a clamp device below to dislocate the neck. Although not ideal, this method can be used for the slaughter of small numbers of birds. In the EU, this method must not be used to slaughter birds more than 5 kg liveweight. The bird is placed in the cone with the head hanging below. Grip the neck in a clamp and firmly pull the handle down to dislocate the neck.

Heavy stick

Two people are needed for this method which, although not ideal, may be used to slaughter large birds such as turkeys and geese. In the EU, this method must not be used to slaughter birds more than 5 kg liveweight.

Hold the bird by the legs (and wing tips if possible), with the head and neck on the ground. An assistant should place a heavy stick (or metal bar) across the neck, behind the head. The person holding the legs should then apply firm pressure to the bar, either side of the head, with his or her feet and immediately pull the bird’s body upwards using sufficient force to dislocate the neck (this may cause some bleeding).

Considerations when using manual dislocation and decapitation during depopulation due to disease control

There are some advantages to using cervical dislocation after simple-stunning using electricity. As discussed previously the ability to kill the bird quickly while it is unconscious and unable to suffer is beneficial for welfare. Additionally as the technique is non-invasive, i.e. the skin remains unbroken, the risk of disease spread is minimised.

There are some disadvantages associated with the technique. The method is often more difficult to perform with larger birds and it requires trained personnel to perform this task humanely. Regardless of the size of the bird, operator fatigue is a real problem. There are also animal welfare implications as the animals may suffer stress due to handling and inversion. The handling also may cause problems for human health and safety especially if killing due to a zoonotic disease.

Conclusion – species and situations

Cervical dislocation should only be used following appropriate electrical stunning. It can be performed to kill birds during disease control, although it must only be performed on a small number of birds and care must be taken to prevent operator fatigue. In Europe, regulations restrict this method to poultry up to 5 kg live weight when using a mechanical method, and 3 kg liveweight when performed manually.    A maximum limit is in place of 70 a day per person.

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