Farrowing crates are metal enclosures used in pig farming to confine a sow (mother pig) during the birth of her piglets and for several weeks afterward while she nurses them. The crate is narrow enough to prevent the sow from turning around, which limits her ability to lie down freely and reduces the risk of her accidentally crushing her newborn piglets. They are one of the most widely used and most controversial pieces of equipment in modern pig production.
How Farrowing Crates Are Built
A standard farrowing crate is a tubular metal frame set inside a slightly larger pen. The crate itself is roughly 7 feet long, 2 feet wide, and 3 feet high. The surrounding pen measures about 7 feet by 5 feet. At the front, there is a built-in feed trough and water supply. Horizontal bars run along the length of the crate, and cross bars over the front two-thirds prevent the sow from climbing upward. The rear panel is adjustable so the crate can be shortened or lengthened to fit sows of different sizes.
Off to the side or front of the crate sits a “creep area,” a small warm zone of about 5.5 square feet designed exclusively for the piglets. This area is heated either by a mat built into the floor or by an overhead heat lamp, giving the litter a place to rest away from the sow’s body. The partitions between neighboring crates are typically about 18 inches high, tall enough to keep piglets contained but low enough that a standing sow can see the sow next to her.
Why Farmers Use Them
The primary reason farrowing crates exist is to prevent piglet crushing. When a sow weighing 300 to 500 pounds lies down, she can trap and kill a piglet beneath her. Crushing accounts for roughly 50% of all piglet deaths and happens most often in the first week after birth. By restricting the sow’s movement, crates reduce the chance that she rolls or drops onto a piglet.
Multiple studies have confirmed that pre-weaning piglet mortality is generally lower in crated systems than in non-crated ones. Conventional crate systems see piglet mortality around 12%, while free farrowing systems report rates between 14% and 20%. That said, the picture is more complicated than it first appears. Research suggests that 30% to 82% of crushed piglets were already weak or compromised before they were crushed, meaning the crate may not have saved them regardless. Some studies have found that while piglets in non-crated systems face a higher risk of crushing, they face a lower risk of dying from other causes, and the overall survival rate can end up comparable.
How Long a Sow Stays in the Crate
A sow is typically moved into the farrowing crate a few days before she is expected to give birth. After farrowing, the sow and her litter remain together in the crate through the nursing period. Natural nest occupation lasts about 7 to 10 days, but in commercial production, sows commonly stay crated until the piglets are weaned at around 3 to 4 weeks of age. In operations with multiple breeding cycles per year, a sow may go through this confinement period repeatedly.
Effects on the Sow
The tight dimensions of the crate prevent a sow from turning around, walking, or engaging in natural behaviors like rooting and nest-building. Research comparing permanently crated sows to those given more space found that crated sows were significantly less active and rolled less frequently, a sign that normal movement is physically blocked rather than simply not chosen. Permanent confinement has been linked to chronic stress by the end of lactation. When sows in one study were released from temporary crating, their levels of a stress-related immune marker (salivary IgA) dropped by 47%, while permanently crated sows showed no such change.
Physical injuries are also a concern. About 2% of sows enter the farrowing house with shoulder lesions, but by the time piglets are weaned, that figure jumps to 24%. These pressure sores develop from repeated contact with the hard floor in a space too small for comfortable position changes. Teat damage is another issue. Permanently crated sows develop 30% to 40% more teat lesions than sows given room to move, likely because they scrape their teats with their hind legs while struggling to stand up and lie down in confined space, and because they cannot move away from piglets during unwanted nursing.
The Welfare Debate
Farrowing crates sit at the center of an ongoing tension between piglet survival and sow welfare. Supporters argue that the crate is a practical, proven tool that saves piglet lives and allows farmers to monitor sows closely during the vulnerable post-birth period. Critics counter that confining an intelligent, social animal in a space barely larger than her own body for weeks at a time causes suffering that outweighs the benefits, particularly given the evidence that many crushed piglets would not have survived anyway.
Animal welfare organizations, including Compassion in World Farming, have campaigned extensively against the practice. Their argument centers on the fact that sows in crates cannot perform nearly any of their natural behaviors: they cannot walk, turn, root in bedding, or build the nests they are strongly motivated to construct before giving birth.
Legislation and Bans
Several countries have moved to restrict or eliminate farrowing crates. Sweden, Norway, and Switzerland have had restrictions in place for years. In late 2025, the UK government announced it would outlaw farrowing crates in England, a decision expected to benefit around 150,000 pigs annually. The European Commission has also been reviewing proposals to phase out caged systems for farm animals more broadly. In the United States, no federal or state law currently bans farrowing crates, and they remain standard practice on the vast majority of commercial hog operations.
Alternatives to Traditional Crates
Several alternative systems aim to give sows more freedom while still protecting piglets. Free farrowing pens are larger enclosures where the sow can move, turn, and interact with her piglets without being restrained. These pens typically include anti-crush rails running around the perimeter, positioned about 6 to 8 inches above the floor and out from the wall, creating a narrow gap where piglets can escape if the sow lies against the wall. Some designs use sloping walls with built-in escape zones at the base.
A middle-ground approach is temporary crating, where the sow is confined in a crate-like structure only during birth and for three to seven days afterward, then the sides are opened to give her the full pen. This approach captures the protective benefit during the highest-risk window while allowing the sow freedom for most of lactation. Research on temporary crating has found that sows become noticeably more active within 24 hours of the crate opening, and their stress markers drop.
Outdoor systems use simple shelters like A-frame huts (about 7 feet by 7 feet) or semicircular “English style” huts made of corrugated metal over a wooden frame. These give the sow full freedom of movement but offer less control over temperature and less ability to intervene if problems arise during birth. Piglet mortality in these systems tends to run higher than in indoor crates, which is why adoption has been slow among large-scale commercial producers focused on maximizing the number of piglets weaned per sow per year.