Foie gras
In 2005, France produced 18,450 tonnes of foie gras (78.5% of the world's estimated total production of 23,500 tonnes) of which 96% was duck liver and 4% goose liver. Total French consumption of foie gras in this year was 19,000 tonnes. In 2005, Hungary, the world's second-largest foie gras producer exported 1,920 tonnes and Bulgaria produced 1,500 tons of foie gras.
Foie gras
The ideology behind foie gras production is the ability that some waterfowl have to expand their esophagus and to gain weight, particularly in the liver, in preparation for migration. Unlike many birds, geese and ducks lack a crop. In the wild, esophageal dilation allows them to swallow large foodstuffs, such as a whole fish, for later digestion. Wild geese may consume 300 grams of protein and another 800 grams of grasses per day. Farmed geese allowed to graze on carrots adapt to eating 100 grams of protein, but may consume up to 2500 grams of the carrots per day. The increasing amount of feed given prior to force-feeding and during the force-feeding itself cause expansion of the lower part of the esophagus.