|Migratory birds in particular, naturally overfeed to endure winter and to fly long distances, and thus, stock fat in their liver.
Following this observation, man has copied this natural operation for 4000 years, to obtain foie gras.
A fattened liver is not a diseased liver: scientific studies prove it. It is a palmiped's liver showing a lipidic excess (fatty liver) due to a rich feeding, without presenting signs of cellular degeneration. Therefore, it is not, as we can hear sometimes, a hepatitis or cirrhosis. In addition, when a fattened poultry is released, the fattened liver goes back to its initial weight, without any modification of its physiological functions. This is called the reversibility of fattened liver and demonstrates that it is obtained naturally.
Before being fattened, poultry are bred. The one-day duckling and gosling are grown up. These young animals are paid particular attention related to ambient temperature and feeding. Cramming, which lasts 2 or 3 weeks according to species, is done progressively, 2 or 3 times a day for geese. The animal must be in good health status and as it does not bear an excessive heat, put in good conditions (venting, air-conditioning).
Corn is the best feeding food because on the one hand, of its high starch content (75%), and on the other hand, of its composition poor of certain enzymes permitting an important accumulation of lipids in the liver.