A sow stall is a metal-barred crate that houses a single sow (female pig) for all or part of her 16 week pregnancy. The floor of the stall is usually concrete, with a slat-covered trench for manure at the rear. A standard sow stall is just two metres long and 60 cm wide. This is just enough space for the sow to stand up in — she cannot turn around and can only take a short step forward or back. The Australian pig industry has committed to voluntarily phasing out sow stalls after the first five days of pregnancy in favour of group housing for gestating (pregnant) sows. Where sow stalls are still in place, regulation currently requires that they not be used for more than six weeks in any gestation (pregnancy) period.
Most indoor pig producers currently house pregnant sows in groups until a week prior to farrowing (birthing) when the sow is moved to a farrowing crate to give birth. After farrowing, the sow may be placed in a mating stall up to five days (for artificial insemination) and then return to group housing. Only a small proportion of pig producers use extensive systems, such as group housing in paddocks or in large semi-outdoor shelters. Sow stalls and farrowing crates are not used in extensive systems; rather, pregnant sows are housed in groups and farrowing sows are housed in huts where they remain until their piglets are weaned.
What are the welfare concerns with the use of sow stalls?
Welfare issues associated with the use of sow stalls arise from the fact that pigs are intelligent, social animals, with a complex range of instinctive behaviours and needs. Pigs that are confined in sow stalls have no opportunity to engage in exploratory and foraging behaviour, or to interact socially with other pigs. As a result, they show high levels of abnormal behaviours (stereotypic behaviours) where they perform an action repetitively (such as biting the bars of the stall and swaying their heads) and have unresolved aggression as they are unable to establish a dominance hierarchy.
Sow stalls can also cause physical problems for the sows. Because sows in stalls are unable to exercise, their muscles and bones deteriorate and they can have great difficulty in standing up or lying down.
What is the RSPCA’s position on sow stalls?
The RSPCA is opposed to the use of sow stalls because of the physical restrictions and adverse effects on movement, behaviour and health, and a lack of social interactions. Sow stalls are not permitted under the RSPCA Approved Farming Scheme standards for pigs. Pregnant sows can be successfully housed in groups, provided that they are properly managed and have sufficient space to avoid aggressive encounters.