Culling is the process by which poultry birds are slaughtered en masse to contain the spread of a disease like bird flu. Usually all the domestic birds in an infected area are culled to prevent further spread of the disease. In India, the infected zone is a 1km radius area from the site of infection. All the domestic birds- in commercial farms, backyard farms, live animal market etc.- in this zone are culled. Culling is done by cervical dislocation following the administration of oral anaesthesia.