Zombie chickens are not the product of a horrible made-for-television movie about the end of the world. They are real.

“Chicken zombies occur when old hens that can no longer lay eggs are incorrectly euthanized by poultry farmers using carbon monoxide,” the training plan instructs. “The hens appear to be dead when buried but inexplicably come back to life and dig themselves out of piles of dead chickens. After reaching the surface, CZ’s stagger about for a period before ultimately expiring due to organ failure.”

source