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Sow stalls and tethers are systems of keeping pregnant pigs in such close confinement they are unable to exercise or even turn around throughout their 16-week pregnancy.
Confined sows show abnormal, repetitive behaviours, and suffer higher levels of foot injuries, lameness, pain from infected cuts and abrasions, weakened bones and muscles, urinary infections, and heart problems.
European Union law forbids the use of sow tethers from 2006.
Sow stalls will be banned in the EU for all but the first four weeks after service from 2013.
Both stalls and tethers are already banned unilaterally in Sweden and the United Kingdom

Sow stalls and tethers, known in the USA as ‘gestation crates’, are two similar systems for keeping pregnant pigs in close confinement. In both systems, the sow is prevented from being able to exercise or even turn round for nearly four months at a time. Her entire 16 and a half-week pregnancy will be spent in a narrow metal-barred stall that is barely bigger than the sow herself. Sow stalls typically measure 0.6-0.7 m x 2.0-2.1 m. Bedding material is not normally provided.

Alternatively, the sow may be tethered to the concrete floor by a heavy collar and chain around her neck or strapped around her middle. Metal bars will partially enclose her to prevent neighbouring animals from fighting. They are kept caged or chained like this in rows, and forced to stand or lie on an uncomfortable floor of concrete and slats.

Legal Situation

European Union law will prohibit the use of sow tethers by 2006.

A recent review of EU pig welfare law included an agreed ban on individual sow stalls for pregnant pigs from 1st January 2013, as well as a requirement for permanent access to manipulable materials. The revised Directive does, however, allow sows to be kept in stalls for the first four weeks after service. Although imperfect, this reform represents a major step forward as sows would normally spend 16 weeks in stalls, unable even to turn around.

A number of EU countries have already taken unilateral action over sow stalls. This system is already been banned in the UK and Sweden. Laws have also been passed to prohibit stalls in the Netherlands, Denmark and Finland:

Denmark - Danish law will forbid the use of sow stalls by 2014.

Finland - Sow stalls will be banned from 2006, except for temporary use, such as for injured animals. Tethers have been illegal since 1996.

The Netherlands - Tethers to be banned in 2002, whilst sow stalls will be prohibited from 2008.

Sweden - Banned sow stalls from 1994, except for temporary use in exceptional circumstances. Tethers have been illegal since the 1970’s.

United Kingdom – Banned sow stalls and tethers from 1999. All the UK’s 600,000 breeding sows are now kept in more humane alternative systems. Most are kept in group-housing indoors, whilst about a quarter are kept outdoors.

Evidence of Suffering in Sow Stalls & Tethers

Foraging and exploring are important behaviours for a sow. Studies of pigs kept in semi-natural conditions show that they are social and inquisitive animals, with a level of intelligence equivalent to the average dog. Experts estimate that pigs will naturally spend 75% of their time rooting in the soil, foraging and exploring. Sow stalls render these behaviours impossible.

Confined sows carry out meaningless, repetitive motions, known as stereotypies. Experts regard these abnormal behaviours as outward signs of stress and suffering. They are the only behavioural means available for the highly frustrated sow to attempt to ‘cope’ with her confinement. Stereotypic behaviours include bar-biting, sham-chewing (chewing the air), shaking the head from side to side, repeated nosing in the empty feed trough, and attempting to root at the concrete floor.

Newly confined sows do not show stereotypic behaviours immediately. The animal’s initial reaction is to try to escape. After a while, the sow appears to quieten down and can become abnormally inactive and unresponsive. The European Commission’s expert Scientific Veterinary Committee (SVC) says that this indicates clinical depression in the sow (SVC, 1997).

The official report from the SVC concluded:

“Since overall welfare appears to be better when sows are not confined throughout gestation [pregnancy], sows should preferably be kept in groups”. It then went on to say that sow stalls have “major disadvantages” for welfare; “The major disadvantages for sow welfare of housing them in stalls are indicated by high levels of stereotypies, of unresolved aggression and of inactivity associated with unresponsiveness, weaker bones and muscles and the clinical conditions mentioned above.” The Report stated, “In general, sows prefer not to be confined in a small space” and they “find the confinement aversive”.

As the SVC noted, sows kept in stall and tether systems often suffer a range of health problems. Compared with those kept in humane alternative systems that allow freedom of movement, confined sows are more likely to suffer foot injuries, lameness, and long-term pain from infected cuts and abrasions. Lack of exercise leads to weakened bones and muscles. Being unable to move freely also causes greater levels of urinary infections. They may suffer heart problems, which can be evident by higher mortalities due to stress when being transported for slaughter.

Many sows are also kept hungry throughout much of their lives. Sows are normally fed restricted rations of concentrated feed. These provide for the nutritional requirements of the sow, but lack the bulk or roughage needed to satisfy her hunger. Confinement prevents the sow from searching for additional food and adds to the suffering involved in the system. The EU’s Scientific Veterinary Committee (1997) concluded, “The food provided for dry sows is usually much less than that which sows would choose to consume, so the animals are hungry throughout much of their lives.”

Not surprisingly, the European Commission has concluded that sow stalls “are causing serious welfare problems to the animals” (EU Commission, 2001). Its accompanying communication to new legislative proposals also pointed to SVC conclusions that serious problems exist “even in the best stall-housing system”, and stated that “No individual pen should be used which does not allow the sow to turn around easily.”

Legal Case Study – the UK

In the early 1990’s, legislation was passed in the UK that saw sow stalls and tethers be phased out over an 8-year period. The new law started life as a Bill presented by Conservative MP, Sir Richard Body, and received overwhelming support from all political parties. Sow stalls and tethers became illegal in the UK on the 1st January 1999. The relevant legislation in England is now consolidated in The Welfare of Farmed Animals (England) Regulations 2000. Schedule 6 of this legislation covers “Additional Conditions that Apply to the Keeping of Pigs”. The relevant section of the Schedule is reproduced below:

Example Legislation: The Welfare of Farmed Animals (England) Regulations 2000; Schedule 6
6. - (1) A pig shall be free to turn round without difficulty at all times.

(2) The accommodation used for pigs shall be constructed in such a way as to allow each pig to -
(a) stand up, lie down and rest without difficulty;

(b) have a clean place in which it can rest; and

(c) see other pigs, unless the pig is isolated for veterinary reasons.
7. - (1) The dimension of any stall or pen shall be such that the internal area is not less than the square of the length of the pig, and no internal side is less than 75% of the length of the pig, the length of the pig in each case being measured from the tip of its snout to the base of its tail while it is standing with its back straight.

(2) This paragraph shall not apply in relation to a female pig for the period between seven days before the predicted day of her farrowing and the day on which the weaning of her piglets (including any piglets fostered by her) is complete.

(3) A person shall not be guilty of an offence in accordance with regulation 13(1) of contravening or failing to comply with this paragraph by reason of the keeping of a pig in a stall or pen -
(a) while it is undergoing any examination, test, treatment or operation carried out for veterinary purposes;

(b) for the purposes of service, artificial insemination or collection of semen;

(c) while it is fed on any particular occasion;

(d) for the purposes of marking, washing or weighing it;

(e) while its accommodation is being cleaned; or

(f) while it is awaiting loading for transportation,
provided that the period during which it is so kept is not longer than necessary for that purpose.

(4) A person shall not be guilty of an offence in accordance with regulation 13(1) of contravening or failing to comply with this paragraph by reason of the keeping of a pig in a stall or pen which the pig can enter or leave at will, provided that the stall or pen is entered from a stall or pen in which the pig is kept without contravention of this paragraph.
The legislation forbids the use of sow stalls and tethers but allows feeding stalls, a welfare-friendly way of feeding pigs kept in group housing. Pigs enter these stalls voluntarily at feeding time, and are free to leave at will.
However, farrowing crates – which severely confine nursing sows or those about to give birth – are still permitted. The same is also true of the newly revised European Union legislation, agreed in June 2001. Nevertheless great progress has been made. From 2013, all pregnant sows and gilts in the EU are required by law to be kept in groups from 4 weeks after service, and in any case, must have enough space to be able to turn round easily.


EU Commission, 2001. Communication from the Commission to the Council and the European Parliament on the welfare of intensively kept pigs in particular taking into account the welfare of sows reared in varying degrees of confinement and in groups. Proposal for a Council Directive amending Directive 91/630/EEC laying down minimum standards for the protection of pigs. Brussels, 16.01.2001. COM (2001) 20 final.

SVC, 1997. The Welfare of Intensively Kept Pigs. Scientific Veterinary Committee.


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