They are killed by having an iron rod rammed into their hearts. It often takes many thrusts into the chest – the slaughterers often miss the heart and instead break ribs or puncture other organs – before the terrified pig finally loses consciousness.

What gas do they use to kill pigs?

Social animals Pigs are stunned using a 70% to 90% carbon dioxide concentrate. They are typically loaded in groups of about half a dozen onto something like a paternoster lift, which lowers them gradually into ever higher concentrations of the gas.

Do pigs suffer when slaughtered?

The sheer number of animals killed makes it impossible for them to be given humane, painless deaths. Because of improper stunning, many pigs are alive when they reach the scalding tank, which is intended to soften their skin and remove their hair.