This is how they "feed" the ducks and geese to fatten them up to make foie gras.
The feed is administered using a funnel fitted with a long tube (20–30 cm long), which forces the feed into the animal's esophagus; if an auger is used, the feeding takes about 45 to 60 seconds. Modern systems usually use a tube fed by a pneumatic pump fed via a slit cut in the esophagus; with such a system the operation time per duck takes about 2 to 3 seconds. During feeding, efforts are made to avoid damaging the bird's esophagus, which could cause injury or death, although researchers have found evidence of inflammation of the walls of the proventriculus after the first session of force-feeding. There is also indication of inflammation of the esophagus in the later stages of fattening. Several studies have also demonstrated that mortality rates can be significantly elevated during the gavage period.