Research progress into the physiological changes in metabolic pathways in waterfowl with hepatic steatosis.

1. When geese or ducks are overfed with a high-energy diet rich in carbohydrates, their liver increases in size by 5- to 10-fold in 2 weeks, which is accompanied by the occurrence of hepatic steatosis. As a result, this distinctive genetic characteristic of waterfowl has been taken advantage of to produce foie gras. 2. When overfed geese were fed a regular diet for a 20-d period of recovery, their liver was restored to the original state. Hence, the entire process is reversible, and cause no lasting cirrhosis or necrosis in the liver. This suggests that waterfowl have a mechanism to protect their liver from the harm caused by severe hepatic steatosis. 3. This paper reviews the formation, physiological changes to metabolic pathways and the protective mechanisms in geese and ducks with hepatic steatosis. Not only will understanding these mechanisms provide ideas for the waterfowl breeding selection for foie gras, it is conducive to improving production efficiency and quality of foie gras. This provides a scientific basis to ensure animal welfare and an approach to the prevention and treatment of fatty liver disease in human.