![Changes in corticosterone concentrations (ng/ml plasma) in male mule ducks during the rearing period (, floor pen), at the time of transfer to individual battery cages () and during the cramming period while being force-fed twice daily and/or occasionally (arrows, upper panel) or systematically (2 lowest panels) tightly constrained in a net for 15 min [before ( ) and 15 min after constraint ( )], or 10 mn after injection of ACTH at doses of 0.625 ( ) or 5mg/kg B.W. ( ). (Mean ± SEM). a, b, c & d: means for a specific group with different letters differ significantly (P <0.05).](https://www.researchgate.net/profile/Daniel-Guemene-2/publication/254887593/figure/fig1/AS:696053120655360@1542963404178/Changes-in-corticosterone-concentrations-ng-ml-plasma-in-male-mule-ducks-during-the_Q320.jpg)
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© World’s Poultry Science Association 2004
World’s Poultry Science Journal, Vol. 60, June 2004
Received for publication October 4, 2003
Accepted for publication April 12, 2004 211
DOI: 10.1079/WPS200314
The past, present and future of force-
feeding and “foie gras” production
D. GUÉMENÉ1* and G. GUY2
1INRA, Station de Recherches Avicoles, Centre de Tours-Nouzilly, F-37380
Nouzilly; 2INRA, Unité Expérimentale des Palmipèdes à Foie Gras, Artiguères, F-
40280 Benquet, France
Force-feeding is an ancient practice, first recorded in ancient Egypt, but until the
1950’s foie gras production remained somewhat limited in volume. Foie gras is
currently produced in various countries but approximately 80% of world production
and consumption takes place in France.
Geese, which were the most common specie been force-fed until recently, now
account for less than 10% of the total world foie gras production. Ducks such as the
Muscovy duck (Cairina moschata) account for less than 5%, and mule ducks for the
rest. Thus, over 35 million mule ducks were force-fed in France in 2001, accounting
for nearly 95% of the domestic foie gras production. This increase was made possible
by technical progress in specific breeding programmes and force-feeding practice.
However, the future of this production is uncertain, at least in Europe. Indeed,
although a number of experimental approaches have shown that there is no scientific
evidence that validates such adverse comment, this procedure is highly criticised in
terms of animal welfare. The Council of Europe therefore adopted two specific
recommendations in 1999 and although its practice is not banned at present, it is
limited to the areas where it is already practised and only under specific rearing
conditions. Therefore, the question is: will it be still possible to produce foie gras in
France or elsewhere in Europe in the future and, if not, where and how will it be
produced?
Keywords: foie gras; waterfowl; geese; ducks; production; rearing conditions; legislation
Introduction
The tradition of force-feeding is very old, probably originating from Egypt; where there is
early evidence in paintings. The Greeks and the Romans perpetuated the tradition, later
expanded during the Middle Ages by Jewish populations. At present, 80% of the world
foie gras production originates from France (CIFOG, 2002), although the genotypes used
and the procedure itself have changed. This paper gives a brief historical review of
production, describes the present situation and provides a prospective overview.
*Corresponding author: e-mail: daniel.guemene@tours.inra.fr
212 World’s Poultry Science Journal, Vol. 60, March 2004
Force-feeding and foie gras production: D. Guémené and G. Guy
Production overview
PAST: FROM ANTIQUITY TO THE XIXth Century
It is generally accepted that geese were one of the first species of bird domesticated in
antiquity (Deffarges, 1973). The first indication of geese being force-fed comes from
Saqqarah in Egypt, with representations of the practice in paintings found in a tomb dated
at 2500 BC. The details of these paintings show meal preparation and the force-feeding
procedure. The operators are seated, hanging ducks and geese from their left hands and
introducing food through the beak with the right hand. Cranes, migratory birds found in
this area, are also represented while being force-fed but, as they are taller birds, the
operator stands. Egyptians were thus probably the first to perform force-feeding, a practice
that lasted in this part of the world for more than 2000 years. Anumber of bas-reliefs show
such scenes, clearly demonstrating that fatty meat of waterfowl and other species of birds
was appreciated, whereas we have no direct evidence of any specific interest in foie gras
consumption.
As revealed by different texts from Athénée, the Greeks later adopted this practice, for
both meat and foie gras production. The Roman army later discovered this product in
Greece and Egypt, and the Roman aristocracy soon considered foie gras as a delicacy,
force-feeding being mainly performed by Jewish slaves. Geese were then force-fed with
figs and the foie gras was given the Latin name “jecur ficatum”; in other words, liver
obtained with figs. The word jecur gradually disappeared and the word ficatum (figs) was
used alone for the organ. It became later figido on the VIII century, then fedie or feie in the
XII and finally foie in French, fegato in Italian and higado in Spanish.
Although it is known that force-fed ducks and geese were consumed during the
medieval period, there is little information regarding the practice. We know that the
tradition was maintained by at least the Jewish population as a way of producing a
substitute for pork fat. It is thought to be the main reason why it spread to various areas
and countries in Europe such as Poland, Hungary, Alsace and South-West France. At the
end of the XVI century, foie gras was regularly present on French aristocratic tables.
However, it was only around the XVIII century that foie gras became a delicacy in France,
numerous recipes being reported from various provinces such as Béarn, Alsace and
Périgord. In the meantime, major technical advances were made, such as the use of corn
instead of wheat, barley or other cereals and the piston funnel, used to drive food down in
the crop, first used in South-West France. Furthermore, by facilitating preservation,
transportation and commercialisation, the development of the sterilisation techniques led
to improved production. Last but not least, although Muscovy duck and probably its
hybrid with the common duck, the mule duck, were already present in farms after the
discovery of America, geese were more or less the only species being force-fed for foie
gras production until the XX century.
PRESENT: FROM THE XX CENTURY
Since the 1950’s tremendous changes have occurred in foie gras production such as the
strains or genotypes involved, the equipment and the overall management used, leading to
substantial increases in production.
Species of interest
The major site of lipogenesis in birds is the liver, whereas in mammals it is the adipose
tissue (Leveille et al., 1975). Birds are consequently more likely to show non-pathological
steatosis. However, although cranes were force-fed in ancient Egypt and turkeys reported
to respond too, only few species and hybrids of waterfowl are nowadays used for foie gras
production. Indeed, only three waterfowl genotypes are currently used for force-feeding in
World’s Poultry Science Journal, Vol. 60, March 2004 213
Force-feeding and foie gras production: D. Guémené and G. Guy
France: the grey Landaise goose strain (Anser anser), the muscovy duck (Cairina
moschata) and the mule duck, a hybrid resulting from an inter-cross between a muscovy
drake and a female common duck (Anas platyrhynchos). In order to warrant the name
“foie gras” the liver should weigh more than 300g and 400g for ducks and geese,
respectively (Decree 95-625). For mule ducks, only livers originating from force-fed
males may be sold as foie gras (Decree 95-625). Furthermore, “magret”, which
corresponds only to the breast meat from a force-fed waterfowl, and “foie gras” labelling
are officially defined and recognised (Decree, 1993). The average respective
performances of these three genotypes evaluated at that time, are reported Table 1 (Guy et
al., 1995). The common duck (Anas platyrhynchos) has also a predisposition to adipose
tissue deposition, but has both a lower ingestion capacity and ability for liver steatosis; it
is therefore not used for cramming (Guy et al., 1999, Hermier et al., 2002, Davail et al.,
2003). It has been shown that a failure in the channelling of hepatic lipids towards
secretion in the plasma and peripheral adipose storage is favourable to establishment of
steatosis (Blum, 1990). For the same reason, several strains of geese are much less
efficient for foie gras production than the grey Landaise goose strain (Fournier et al.,
1997).
Table 1 Characteristics of 3 different genotypes of waterfowl submitted to force-feeding (adapted from,
Guy et al., 1995).
Geese Mule Duck Muscovy Duck
(M & F) (M) (M)
Body Weight (g) 7434a6473b6565b
Breast Muscle Weight (g) 214c273b318a
Foie gras Weight (g) 768a677b553c
Foie gras fat loss (%) after cooking 13.9a40.7b56.0c
Lipids (%) foie gras 54.6a60.5b62.6b
Triglycerides (% / total lipids) 92.2a94.4b95.7b
Phospholipids (% / total lipids) 3.5a1.95b1.5b
M: male, F: female.
a, b, c means associated with different letters differ statistically (P <0.01).
Geese produce the heaviest livers with the least fat loss, however they currently account
for less than 5% of French production (approximately 8% of world production). Geese
have poor reproductive ability and consequently gosling cost is high, their meat yield is
low and their management is more time consuming. Muscovy ducks produce a large
amount of meat, but the liver is smaller in size and of somewhat different quality.
Furthermore, this duck is more sensitive to disease. Finally, the mule duck appears as to be
the best choice for force-feeding purposes. It has a good potential for production and is
easier to manage. Moreover, the problems of infertility in the production of this hybrid
have been mostly solved with artificial insemination.
In France, five breeding companies are working on genetic improvements in waterfowl
genotypes used for force-feeding. Their activities are mainly focused on duck genotypes,
but three of them still have ongoing programmes on geese. Most if not all the breeding
programmes appear to be taking place in France, although some of the genetic resources
presently used (such as the female Pekin duck) may originated from foreign countries. The
adaptability of mule ducks to force-feeding has been improved, because both the female
Pekin duck and more recently the Muscovy drake have been submitted to specific
selection programmes. The first parameter to be selected was the production of foie gras.
The average weight of foie gras is now sufficient and these programmes are no longer a
priority; breeding companies will now aim to reduce the duration of cramming. Due to the
214 World’s Poultry Science Journal, Vol. 60, March 2004
Force-feeding and foie gras production: D. Guémené and G. Guy
demand by the slaughtering houses for better carcass presentation, the breeding companies
have also recently selected parental strains in order to obtain hybrids with white plumage.
This has also been achieved by fixing this character in the female and by using phenotypic
mutation in muscovy ducks. Lastly, as the French market requires, body conformation has
been improved to produce larger breast muscle i.e. “magret”. As shown in Table 2, the
improvement over the last 10 years has been marked. Arecent substantial increase in the
demand for duck meat was associated with the BSE crisis in Europe. Although the crisis
has passed, demand remains high.
Table 2 Evolution of zootechnical performance of mule ducks (GTE Palmipèdes gras: CIFOG, 2002,
2003).
1991 1996 2001 2002
Number of force-fed ducks / flock 173 290 558 618
Age at force-feeding (days) 89.3 86.7 88.6 89.4
Duration of force-feeding (days) 15.8 14.9 13.8 13.4
Amount of corn (kg) 12.3 11.4 10.7 10.5
Foie gras weight (g) 516 526 539 549
Meat (2 legs + 2 breast) (kg) 2.30 2.35 2.50 2.50
Equipment
Around 1950, the composition of the diet used during the force-feeding period for foie
gras production only consisted of moderately cooked non-ground corn grains. The need
for an appropriate way to deliver the feed led to the development of a manual screw
dispenser, which was later automated by the addition of a motor. This equipment has been
constantly upgraded, and nowadays a number of producers are using different models of
this equipment, some of them being very sophisticated. By the end of the 1980’s, French
producers brought a new concept from Israel, the pneumatic dispenser, a device that can
deliver a corn mash diet mixed with water at a high speed. This method was adopted
within a short period and drastic changes have been observed in field practice.
Rearing conditions were also modified over the same period and ducks were placed in
individual cages during the cramming period instead of in collective pens, the main
advantages being that there is no risk of confusing the ducks and that they always remain
in the right position. These practical changes together contributed to enhancing
productivity, with up to 400 ducks being force-fed by one person per hour. However, new
improvements were still to come. The general concept of food delivery was retained but
improved by using a hydraulic dispenser, which is more powerful than the pneumatic
dispenser. The advantage of this equipment was the opportunity to incorporate a certain
amount of uncooked whole corn grain into the mixture. This was important for geese
because, in contrast to the mule ducks, they are unable to obtain maximum value from
corn when incorporated in the diet under mash form. (Table 3).
Table 3 Foie gras weight (g) according to corn presentation in the diet: whole grain, mash or as a mixture
for mule ducks (Robin and Castaing, 1996) and geese (Dubois et al., 1994).
Foie gras weight (g) Grain Mixture Mash
Male mule Ducks 559 559 557
Geese 959 931 664
World’s Poultry Science Journal, Vol. 60, March 2004 215
Force-feeding and foie gras production: D. Guémené and G. Guy
Other features have been added, such as an incorporated mixer, an automatic shift and
automated control of the amount of corn delivered. This new equipment has been very
successful and is presently the most widespread, especially in larger units having up to one
thousand ducks at a time.
Specific barns to raise ducks during the cramming period have also been set up.
Working conditions have been optimised and ambient conditions, such as temperature,
moisture and air renewal, fully controlled. The development of this kind of building has
contributed to better economic performance.
There will be a new revolution in rearing conditions in the near future, with the official
ban on individual cages (T-AP 95-20).
Breeding and force-feeding management
Waterfowl have a spontaneous tendency to overfeed, a tendency which, at least for
geese, is probably related to the pre-migratory behaviour of their ancestors. Force-feeding
results in an extra-physiological state, with extreme lipid storage in the liver and in
subcutaneous tissue. Knowing that lipid synthesis and storage capacities can be
spontaneously and transiently stimulated, producers have developed specific feeding
programmes adapted to waterfowl, which are to be force-fed later. In practice, the duck
breeding period can be subdivided in three phases:
-Starting period: Birds are fed ad libitum from the time of hatching until 6 to 9 weeks
of age.
-Growing period: Birds are feed restricted for a period of 3 to 5 weeks.
-Pre-force-feeding period: Birds are fed as much as possible for 3 to 10 days.
Two procedures are commonly practised during the growing and pre-force-feeding
periods; i.e. hourly feed restriction and quantitative feed restriction (Robin and Castaing,
2002). Under the hourly feed restriction procedure, ducks are provided with a large
amount of food, but access to feed troughs is limited to a given period of time. Under the
second, ducks are provided with an amount of food which is lower than ad libitum
consumption. During the pre-force-feeding period, the duration of access (hourly) or
amount of food available (quantitative) is increased in order to reach consumption levels
higher than regular ad libitum levels. Most of the ducks are ready to be force-fed at 10 to
14 weeks of age, depending upon the type of production (standard or “label”). This
procedure of pre-force-feeding has three objectives:
- Increase in “crop” size, which is poorly developed in waterfowl species.
- Stimulation of digestive secretions necessary for the assimilation of a large amount of
food.
- Onset of liver steatosis (the liver can weigh up to 180g by the end of this period).
As recently shown (Robin and Castaing, 2002), such a specific programme results in a
reduction in the duration of the force-feeding period. For example, these authors reported
that mule ducks produced foie gras of average weights of 546g (hourly programme) and
572g (quantitative programme), respectively, after a force-feeding period lasting 9.5 days
(19 meals) and an overall ingestion of 8.5kg of corn.
In addition to the productivity resulting from the procedures described above, new diet
presentations have provided nutritional advances favourable to establishment of steatosis.
Corn remains the main ingredient in the force-feeding diet, both because it is a low cost
ingredient and also because of its high starch content, starch being one the best substrates
to stimulate neo-lipogenesis in bird livers. However, although corn remains the basis of
the diet, preparation as a water mash makes possible the addition of various minor
ingredients, with two main objectives:
216 World’s Poultry Science Journal, Vol. 60, March 2004
Force-feeding and foie gras production: D. Guémené and G. Guy
- Enhancement of the response to force-feeding; faster establishment of steatosis can
either increase the final foie gras weight or allow a reduction in the duration of
cramming.
- Improvement in the technological quality of the foie gras by reducing fat loss during
cooking.
As indicated in Table 4 (Robin and Castaing, 1998), recent results suggest that the field
of investigation is large and promising.
Table 4 Influence on liver quality of supplementing the force-feeding diet with starch or milk powder.
Adapted from Robin and Castaing, 1998.
Parameters Control Starch Milk Starch & ANOVA
powder milk powder P< 0.01
Starch content (% diet) 71.9 74.3 72.1 74.3
Protein content (% diet) 8.44 8.44 10.04 10.04
Foie gras raw weight (g) 574c647b602c688a**
Fat loss (%) cooking 14.9a22.9b13.9a22.4b**
Foie gras (g) cooked 489b491b522a531a**
Economy
As already stated, France is the world leader in foie gras production and consumption.
Indeed, France even reinforced her world leadership position in 2002, with the production
of 83% of the available world supply compared to 74% in 1995. Duck foie gras represents
the greater part of national production (16429 tons, over 95%, <5% from Muscovy ducks),
in spite of a significant recent increase in the production of goose foie gras (586 tons, or
about 25% of the world goose foie gras production). However, production has also
increased throughout the world, although in most countries local production represents
only small volumes. It includes most of the Eastern Europe countries, with the noticeable
exception of Poland, which has recently banned foie gras production, Belgium, Spain and
also all the countries from the American continent. Although mule ducks are used for meat
production in Asia, little information is available on practices there. African countries do
not seem to be involved in foie gras production with the exception of Madagascar. The
countries with significant foie gras production in 2002 were:
-Spain: foie gras production is only a recent development in this country but it
contributes to about 1% of the world production (WP).
-Israel: It is a traditional producer of goose foie gras, with a stable production
representing around 1.5% of the WP.
-Bulgaria: Produces mainly duck foie gras (5% of the WP). There has been a significant
increase in production recently and the major part of its production (88%) is exported to
France.
-Hungary: It is the leading country in the world for goose foie gras production, with 60%
of the WP (about 1780 tons) and around 9% of the total foie gras WP (2850 tons in
2001). The grey Landaise goose strain is used for force-feeding. Duck foie gras is also
produced in this country and accounts for approximately 40% of their total production.
In France, producers can be subdivided in two types of organisations:
- Small units using a short path strategy. In such units, producers are involved in all the
stages of production: bird rearing, cramming, slaughtering on the farm, meat and foie
gras processing and lastly direct marketing of their products. It is difficult to evaluate the
World’s Poultry Science Journal, Vol. 60, March 2004 217
Force-feeding and foie gras production: D. Guémené and G. Guy
exact contribution of these small producers to the national market, but it is thought to
represent around 12% of total French production (Magdeleine, 2003). The number of
units is estimated to be between 1000 and 1500.
- Large units using to a long path strategy. In this approach, specialised operators
undertake the different stages. The different participators in this path of production are
generally associated in co-operatives. There are at present about 45 companies, but there
is a strong tendency to increased size after take-overs and restructuration. The first stage
is focused on breeding (specific feeding strategies described above) of ducks and geese.
Then there are farmers who specialise in the force-feeding stage. These producers
generally work under contract with a co-operative. Such organisation of production has
been associated with increased production and reduction in prices, and producers have
progressively compensated for this by increasing the sizes of units to preserve their
income (Table 5). Thus, duck flock size can reach up to 4000 birds during the rearing
period and up to 1000 ducks during the cramming period. Special administrative
authorisation is required to operate units over a threshold of 1000 ducks (Decree 95-
625). The number of flocks raised per year per farm ranges from 9 to 10, while a
producer can force feed around 20 flocks per year, successively.
Table 5 Evolution of prices and duck flock sizes between 1995 and 2002 (CIFOG, 2002, 2003).
1995 2001 2002
Price: one duck redy to be force-fed (€) 8.83 7.91 8.06
Average flock size during the rearing period 1745 2324 2486
Price: foie gras (€/kg) 18.23 17.07 18.91
Price: one force-fed duck (€) 15.76 15.25 14.89
Average flock size during the force-feeding period 289 558 618
Birds are usually slaughtered in large, modern slaughterhouses, i.e. having a potential
for slaughtering over 2500 birds per hour. Whatever the procedure of liver extraction,
whether immediate or on the following day after cooling, carcasses are always processed
according to automated conditions. Thirty-one companies are involved in this activity in
France. The next processing stage is even more concentrated and involves only 16 units.
After being processed, the product is marketed as a delicacy, directly to consumers,
restaurants and delicatessens on the one hand, and in supermarkets on the other; the latter
having approximately 75% of the total production. Foie gras production leads to the
marketing of a variety of products, such as the meat parts, i.e. the breast muscles
corresponding to the Pectoralis major which are called “Magret” and are the more
valuable, and the “Aiguillette” corresponding to the Pectoralis minor. They are prepared
in different ways and sold as fresh meat, roasted, smoked, dried, or even cooked in their
own fat. This last form is called “Confit” and is also used for legs, wings and gizzards.
Other parts such as hearts and small pieces of meat are also marketed fresh or in various
preparations. Foie gras is served as a fresh product in top of the range restaurants. The
tinned and the half-cooked foie gras, with duration of preservation of four years at room
temperature and six months at +4°C, respectively, represent the highest quality preserved
products. They are sold as “foie gras entier” and “foie gras”. The second choice foie gras,
called “Bloc”, are crushed and then mixed and presented as a roll. Foie gras can also be
prepared with truffles (up to 3%). Last but not least, various products include pieces of
foie gras, but they cannot be called foie gras. However, if it represents more than 50%, it
can be called “Products containing foie gras”. The economic importance of foie gras
production is high since it is estimated that it involves about 30.000 direct and 100.000
indirect jobs (CIFOG, 2002).
218 World’s Poultry Science Journal, Vol. 60, March 2004
Force-feeding and foie gras production: D. Guémené and G. Guy
Animal welfare
Foie gras production is strongly criticised in Europe as it is considered to be detrimental to
animal welfare. However, no scientific data is to date available to prove these allegations.
In order to evaluate the impact of such practices for birds, a number of scientific
investigations have been set up in the major fields of physiology and endocrinology,
behaviour and nociception.
PHYSIOLOGY
One of the first studies conducted in this area concerned the reversibility of steatosis.
Several experiments were carried out (Babilé et al., 1996, 1998; Bénard et al., 1996, 1998)
and they indicated that steatosis is fully reversible, after a short period both for geese and
mule ducks, even after 3 successive force-feeding periods. Moreover, liver function and
histological structure are preserved (Babilé et al., 1996, 1998; Bénard et al., 1996, 1998).
Different stress indicators such as changes in corticosterone (Faure et al., 1996, Guémené
et al., 1996, 1998a, 2001) have been used to investigate acute and chronic stress related to
force-feeding and have reinforced our knowledge regarding duck and goose physiology. It
has been reported that neither the first episode of force-feeding nor subsequent episodes
induce any significant increase in plasma corticosterone levels when ducks are kept in
individual cages. On the other hand, significantly higher corticosterone levels were
Cramming Period
D-5 D13D1 D2 D8 0.625
ACTH (µg/kg B.W.)
D10 5
Systematic Treatme
n
ab
d
ab
a
bc
0
25
50
75
100
125
Force Fed & Systematic Treatm
er
0
25
50
75
100
125
Transfer
Pre-cramming
period
Force Fed & Occasional Treatmer
a
b
ab ab ab
dcd
bc
a
ab
d
ab ab
aaa
bc
bc
cd
cd
ab
ab aa
ab
a
bbc
c
b
ab ab
ab ab
ab ab
c
ab
Figure 1 Changes in corticosterone concentrations (ng/ml plasma) in male mule ducks during the rearing
period (, floor pen), at the time of transfer to individual battery cages () and during the cramming period
while being force-fed twice daily and/or occasionally (arrows, upper panel) or systematically (2 lowest
panels) tightly constrained in a net for 15 min [before ( ) and 15 min after constraint ( )], or 10 mn after
injection of ACTH at doses of 0.625 ( ) or 5mg/kg B.W. ( ). (Mean ± SEM). a, b, c & d: means for a specific
group with different letters differ significantly (P<0.05).
World’s Poultry Science Journal, Vol. 60, March 2004 219
Force-feeding and foie gras production: D. Guémené and G. Guy
measured after handling during the rearing period in birds raised in collective pens.
Further experiments have shown that the corticotrope axis was fully functional, and that
these ducks were able to secrete corticosterone after a physical stress such as restraint in a
net for 15min (Guémené et al., 1998b) (Figure 1).
Behaviour
One major criticism based on the excessive amount of food that the birds have to ingest
daily during the force-feeding period was counteracted by the observations of geese
spontaneously ingesting large amounts of grass or over 3kg of carrots per day. Likewise,
spontaneous hyperphagia in ducks has been confirmed in that spontaneous daily intake
(up to 750g) has been reported (Guy et al., 1998). The behavioural responses of geese and
ducks previously trained to move from their rearing pen to a feeding pen in order to have
access to their food have also been studied. After a training period, half of the birds were
fed using a force-feeding procedure, the amount of food ingested being adjusted to the
amount spontaneously ingested by control birds. Ducks exhibited only partial avoidance
of force-feeding and no sign of aversion was observed in geese (Faure et al., 1998,
Guémené et al., 1998b). Moreover, it was observed in a subsequent experiment (Faure et
al., 2001) that the flight distance of ducks was greater when faced with an unknown person
than with the caretaker, i.e. the person who performed the force-feeding procedure.
Furthermore, there was no development of aversion to the operator throughout the force-
feeding period since the flight distance became shorter with time (Faure et al., 1998,
2001). Lastly, behaviour has been observed in ducks force-fed in different housing
systems. No significant changes were observed in duck behaviour throughout the
procedure, with the exception of panting behaviour, which increased in frequency by the
end of the force-feeding period, the increase being greater for ducks housed in individual
cages. This could indicate a defect in the thermoregulatory process. On the other hand,
individual cages were not associated with the expression of stereotypy, passive behaviour
or any indication of frustration (Faure et al., 2000). Ducks housed in these cages were
even found to be more active than those raised in collective cages.
Nociception
Animal activists often maintain that this procedure is painful for the birds. Further
investigations have been set up to look at potential signs of pain in ducks at different
stages of the force-feeding period. These practical situations have been compared to
pharmacologically treated ducks in which necrosis of the crop was provoked under
anaesthesia by an irritating substance (Servière et al., 2002). Local inflammatory
processes resulting in extra-vasation responses, revealed by a specific marker, were very
intensive in treated control ducks, but were not observed in force-fed ducks at the
beginning or in the middle of the force-feeding period. Nevertheless, slight symptoms
were observed in a few ducks by the end of the force-feeding period, probably due to
moderate inflammation. In similar experimental conditions, observations of peripheral
and central neuronal activation showed indications of pain signalling in the medulla and
brains of chemically treated birds, but not in force-fed ducks.
Although there is a need for further investigations in all these areas, the present results
do not support criticisms of force-feeding and foie gras production.
Is there any future?
”Grammont’s Law”, passed in France in 1850 at the instigation of the founders of the
French Society for Animal Protection (SPA) was one of the first, if not the first, laws
220 World’s Poultry Science Journal, Vol. 60, March 2004
Force-feeding and foie gras production: D. Guémené and G. Guy
devoted to animal protection in the world. Under this law, mistreatment of domestic
animals was subject to punishment, but only if performed in public. Since then, concern
about animal welfare has sharply increased and European legislators have now introduced
specific welfare regulations. In Europe, two independent organisations are in charge of the
legislation concerning domestic animal welfare: these are the Council of Europe and the
European Union. Ageneral convention covering all domestic species (1976) and a similar
directive (98/58/CE, 1998) have been adopted by the standing committee of the European
Convention (Council of Europe) and the European Union, respectively. Both of these texts
apply to all domestic species and therefore to waterfowl. Furthermore, the standing
committee of the European Council adopted three specific recommendations concerning
waterfowl in 1999. These three recommendations specifically concern domestic ducks
(Anas platyrhynchos) (T-AP [94/3]), Muscovy ducks (Cairina moschata); mule ducks, (a
hybrid of domestic and muscovy ducks) (T-AP [95/20]) and domestic geese (Anser sp.) (T-
AP [95/5]). Article 9 paragraph 3 of the Convention states that these recommendations
should come into force in December 1999, and recommendations will to apply to new
accommodation or the replacement of existing systems from 31st December 2004. All
husbandry systems will be required to meet the requirements of the recommendations
from the 31 December 2010.
The most important implications of the recommendations are:
- the use of completely slatted floors and individual battery cages will be forbidden.
- the production of foie gras must be carried out only where it is current practice and then
only in agreement with the already existing legislation in the member states concerned.
- feed restriction strategies, ahemeral rhythms and split photoperiods are to be banned.
- the use of pipette type watering systems is to be prohibited.
- mutilation of ducks shall be prohibited and therefore beak and claw trimming are not
allowed for domestic ducks and geese and only tolerated under severe restrictions for
Muscovy and mule ducks.
- waterfowl should not be plucked alive.
- carrying birds with their heads hanging downwards or by the legs alone will not be
tolerated.
Moreover, a potential implication of two articles of the recommendations is that
commercial duck breeders may have to obtain specific authorisation before a new strain
can be introduced to the market.
Meanwhile, the European Commission has commissioned a report from the scientific
veterinary committee on practices designed to fatten waterfowl. Expert advice from the
scientific committee on animal health and animal welfare stated that ”force-feeding, as
currently practised, is detrimental to the welfare of the birds”. It is therefore possible that
the Commission will issue a directive on the husbandry of waterfowl that is even more
restrictive than the existing proposals concerning the production of commercially bred
birds.
In short, no more individual cages can be built after December 2004, and this equipment
should have disappeared by December 2010, in spite of the fact that there is no scientific
evidence of having negative consequences for the ducks housed under such conditions.
There is no such system available on the market at present. Production costs will therefore
rise and, in the meantime, working conditions will become worse for handlers. In addition,
with regards to the specific problem of foie gras production, it is stated that it will be
possible to carry out this procedure only in traditional areas of production. Mainly for
political reasons, a number of European states have decided to ban foie gras production,
among them Italy and Poland which had a tradition of production at that time. There is
therefore strong pressure in Europe from small but very effective animal protection groups
World’s Poultry Science Journal, Vol. 60, March 2004 221
Force-feeding and foie gras production: D. Guémené and G. Guy
to forbid its production everywhere. However, current and proposed regulations only
apply to existing EU State members and/or the EC members who have ratified the
convention, whereas due to the WGO agreement trade cannot be prohibited. Current
regulation of poultry husbandry practices does not apply to other foreign countries. Such
countries could then expand poultry production such as foie gras to a considerable degree‚
so as to meet market demands in Western European countries. Such a situation would
result in unfair competition because products would be imported without the sanitary and
welfare warranties applicable to present EU members. If such a situation were to occur
then welfare and sanitary problems will not disappear but will be swept under the carpet
only to occur elsewhere.
Conclusion
Although they are not involved in the production of foie gras, a number of European state
members want to ban it in all European state member countries. Practised for thousands of
years, foie gras production can be considered as part of French culture and is of great
economic significance. Based on the extra physiological use of a natural fattening
phenomenon, foie gras has been recognised as a non-pathological and non-harmful
product. Many changes have been made in order to improve both working conditions for
the producers and animal welfare. It has been shown that physiological indicators of
stress, nociceptive signs and behavioural responses were hardly affected by the force-
feeding procedure. Other research programmes are still in progress in various fields such
as genetic adaptability of birds, environmental preservation and rearing conditions and
they should also contribute to improvements in the overall conditions of foie gras
production. Such scientific results and the economic background should be taken into
account when new laws and recommendations are established rather than
anthropomorphic considerations. However, it is at present rather difficult to anticipate
what the overall context of this type of production will be in Europe in the future.
Acknowledgements
The authors thank Doreen Raine for greatly improving the quality of the manuscript.
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