Foie gras, a French term for “fat liver,” is the product of processed livers of force-fed waterfowl such as ducks and geese (Duncan, 2009). Although there are always compliments about how good foie gras tastes, such a delicious dish has very controversial issues with regards to the production process, confinement, and other animal welfare concerns. Common issues include the force-feeding procedure, the unnatural feeding regime, barren and confining housing, mortality and disease (Duncan, 2009). This paper is going to review the force-feeding procedure, which is the key to the production of foie gras, and its subsequent effects to ducks and geese that usually draws the most attention in terms of animal welfare.
Every year, the number of ducks and geese raised for production of foie gras is over 20 million in the world (Duncan, 2009). France, which is famous for foie gras, has continuously been the biggest producer of foie gras on earth (Duncan, 2009). In 2007, this very country contributed 18 million ducks and geese for the production of foie gras (Duncan, 2009). Around 80% of world production and consumption of foie gras is in France (Guémené and Guy, 2004). Quebec is the only province known to be producing foie gras in Canada, with approximately hundreds of thousands of ducks and geese raised for the product every year (Duncan, 2009).
Force-feeding is a very old technique, which can be traced back to ancient Egypt (Guémené and Guy, 2004). The earliest force-feeding procedure was found in paintings in a tomb 2500 BC which illustrate seated workers with ducks and geese hanging from their left hands, and feed for force stuffing waterfowl through the beak on right hands (Guémené and Guy, 2004). In addition, geese were the first species used to perform this procedure (Guémené and Guy, 2004). Although this old practice had been used for almost 5000 years (Guémené and Guy, 2004), the production of foie gras never got publicly questioned until 1950’s, when the equipment and the overall management changed tremendously in response to increasing demand of foie gras (Strang, 2007). This is where mass production began and consequently led to ascending awareness and concerns about waterfowl welfare.
Geese were the only dominant species for foie gras production before twentieth century, while mule duck, and Muscovy duck are the dominant ones in this industry today (Guémené and Guy, 2004). In order to be qualified as “foie gras,” the liver of ducks and geese should weigh more than 300g (Guémené and Guy, 2004), which is six to 10 times heavier than the size of a normal duck or goose liver (Duncan, 2009). The force-feeding management can be divided into three phases, the starting period, growing period, and pre-force-feeding period (Guémené and Guy, 2004). Hourly feed restriction and quantitative feed restriction are applied for latter two periods which enhance the digestive secretions for enormous amount of food and stimulation of steatosis in the liver (Guémené and Guy, 2004). Rearing conditions are also changed in order to meet more efficient production of foie gras. Ducks and geese are confined in individual cages today, rather than kept in collective pens before (Guémené and Guy, 2004). The advantage of doing this is to avoid confusion among ducks and to ensure that they do not move (Guémené and Guy, 2004). No movement means no energy utilized therefore accelerate the rate of production. Unfortunately, this does not seem to be an advantage for ducks and geese in terms of animal welfare.
The procedures depicted above are quite stressful. In a study, based on previous finding that “stress induces a decrease in productivity,” Guémené and colleagues observed a significant decrease in body weight for all groups in their study (Guémené et al, 2001). They attributed this result to the use of individual cages, which was considered to be chronic stress for ducks and geese (Guémené et al, 2001). Corticosterone, one of avian stress hormones produced by the adrenal gland under stressful condition, is another indicator (Heath and Meneley, 2010). It is found that level of corticosterone in blood was high following a waterfowl’s initiation to being force fed and returned to normal when the waterfowl got used to the procedure (Heath and Meneley, 2010). It might be due to habituation of the procedure that make the level of corticosterone went down eventually, but it did not change the fact that ducks and geese are actually under stressful condition during force-feeding management.
Force-feeding procedure is extremely aversive experience for ducks and geese. Other than stress, force-feeding also leads to intensive resistance to the procedure, four to 20 times higher mortality rates caused by throat injuries and liver failure, as well as lack of chance to express normal behavior in individual cages (Duncan, 2009). Some recommendations are listed in Duncan’s report, which are worth mentioning. First, any feeding method should not cause stress to waterfowl. Second, any method of increasing liver size should not affect liver function and cause pain to waterfowl. Third, the housing system should be roomy enough so that it allows waterfowl to express normal behavior (Duncan, 2009). If above three conditions can be met, production of foie gras should be tolerable.
Work Cited
Duncan, I. 2009. The scientific case against foie gras. BCSPCA. http://www.spca.bc.ca/assets/documents/welfare/foie-gras/foie-gras-scientific-report.pdf
Guémené, D., G. Guy. 2004. The past, present and future of force-feeding and "foie gras" production. Worlds Poultry Science Journal. 60:210-222.
Guémené, D., G. Guy, J. Noirault, M. Garreau-Mills, P. Gouraud, J. M. Faure. 2001. Force-feeding procedure and physiological indicators of stress in male mule ducks. British Poultry Science. 42:650-657.
Heath, D., A. Meneley. 2010. The Naturecultures of Foie Gras. Food, Culture & Society. 13:421-452.
Strang, J. 2007. "Foie Gras": As Seen from Southwest France. Gastronomica. 7:64-69.
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