To produce "foie gras" (which literally means "fatty liver"), workers ram pipes down male ducks' or geese's throats two or three times daily and pump as much as 4 pounds of grain and fat into the animals' stomachs, causing their livers to bloat to up to 10 times their normal size. Many birds have difficulty standing because of their engorged livers, and they may tear out their own feathers and cannibalize each other out of stress.

The birds are kept in tiny wire cages or packed into sheds. On some farms, a single worker may be expected to force-feed 500 birds three times each day. Because of this rush, animals are often treated roughly and left injured and suffering.

A PETA investigation at Hudson Valley Foie Gras in New York (then called "Commonwealth Enterprises") found that so many ducks died when their organs ruptured from overfeeding that workers who killed fewer than 50 birds per month were given a bonus. Many ducks develop foot infections, kidney necrosis, spleen damage, bruised and broken bills, and tumor-like lumps in their throats. One duck had a maggot-infested neck wound so severe that water spilled out of it when he drank.

Other investigations at Hudson Valley Foie Gras and America's other leading foie gras producer, Sonoma Foie Gras in California, revealed that ducks were crammed into filthy, feces-ridden sheds and that others were isolated in wire cages that were so small that they could barely move. Investigators also observed barrels full of dead ducks who had choked to death or whose organs had ruptured during the traumatic force-feeding process. The investigators rescued 15 ducks, including two who were being eaten alive by rats because they could not move.