After about two years of exploitation, they’re “spent” and their egg production declines.

Once they were no longer profitable, tens of thousands of hens were roughly yanked out of their cages, slammed against metal boxes, stuffed into the boxes, and then crudely gassed with carbon dioxide—an acidic gas that can cause extreme pain.

Many hens survived all that, only to be dumped onto a conveyor belt and then into trucks, where they landed amid massive piles of their dead cagemates. Workers tried to kill the survivors by slamming them against the trucks, beating them with a piece of wood, or breaking their necks.

Some hens survived even that—and were left to die in agony, likely of suffocation, under the bodies of other chickens.