Culling a chicken refers to the process of removing and killing unwanted chickens from a flock for various reasons. The reasons for culling include:

• Egg production: Male chickens are considered redundant to the egg-laying industry and are usually killed shortly after being sexed, which occurs just days after they are conceived or after they hatch. Hens that are non-laying or low producing are also culled.

• Health: Sick or diseased chickens are culled to prevent the spread of disease to other birds in the flock.

• Behavior: Aggressive roosters, birds that exhibit bird-on-bird aggression, egg-eating, and chick murder are also culled.

The methods of culling include cervical dislocation, asphyxiation by carbon dioxide, and maceration using a high-speed grinder. The most humane method is cervical dislocation, which consists of snapping an individual chickens spinal cord and is used when only a few birds are being killed at a time.

Sight culling and culling by individual inspection are the two types of culling used to remove inferior birds. Sight culling of pullets when being placed in the laying house removes the obviously undersized, underdeveloped, weak, crippled, or diseased birds which have very little chance of becoming good laying hens.

It is important to cull chickens humanely and as fast and painless as possible. Delay culling if a significant portion of the flock is suffering or recovering from a minor disease or molt.