Gestation-sow housing has certainly become a lightning rod for the industry. Everyone seems to have an opinion on the topic, and there are as many management and housing options as there are opinions. A one-size-fits-all solution is not likely to surface.

Whether housing gestation sows in stalls or groups, it’s the quality of individual pig care that’s most important, says Tim Safranski, University of Missouri Extension swine specialist. “Managed correctly, any of the housing systems can work. If we look at the body of scientific literature, it doesn’t matter how sows are housed. It matters more how they are cared for; in fact, with proper attention and management, performance can excel in any system.”

Safranski describes proper animal care as providing basic needs like food, water and protection from weather. Of course, it doesn’t stop there. It also means reducing hazards and competition between individual animals as well as allowing sows to express normal behaviorial patterns.

“With all of the sow-housing options available, either gestation stalls or group housing can fit most of those needs,” he says. “None of the housing options fit every point perfectly.”  Safranski points to a 2005 paper from the American Veterinary Medical Association that sums up this opinion. It says, “no existing housing system for pregnant sows is better than another.”

Stalls may be more effective in preventing fighting, thereby reducing animal stress and injury. Stalls also better facilitate handling situations such as vaccinations, administering medical care and artificial insemination.

“Stalls make individual care much easier,” Safranski says. “We can get the skinny sows more food and give the fat sows less.”

On the other hand, stalls restrict movement which may cause joint stiffness. In addition, some natural behaviors, like socializing and foraging, are restricted. Stalls also make sows entirely dependent on caretakers to provide basic needs and physical comfort. Depending on the management and the workers’ diligence, those results can vary significantly.

Sows in stalls require careful, daily observation. Providing an exercise pen for sows that show signs of physical challenges may help the overall outcome. “If we see a sow having trouble walking, giving her space to exercise and stretch can benefit the system and enhance productivity,” he notes.

Group housing allows sows more social interaction and offers freedom of movement, but at the same time, it makes individual feeding and specialized care much more challenging.

Sow groups can range in size from five or six sows to 80 or more, depending on the system and the management abilities. But regardless, sorting is essential, Safranski says. He suggests creating groups based on the animal’s size, appetite and body condition.

“Somebody is still going to be the boss pig,” he says, “but if we can at least get the animals sorted evenly to start with, they’re going to maintain that uniformity a lot better than if you don’t sort.”

Once a group is created — especially in the case of small groups — they should remain fixed. Changing sows within a group will lead to increased fighting. If sows must be mixed, it’s helpful to mix them into a completely new pen to reduce territorial behavior. “Get them all out, walk them down the aisle and put them somewhere else,” he suggests. “That way, nobody is invading another sow’s house.” Always make sure the pen offers adequate space for the size of the group — and the size of the sows.

In very large groups, the sows may fight less because they can’t as easily figure out who the bullies are and who to pick on, Safranski says. It also can be easier for timid sows to escape and hide out. Therefore, very large groups are a better fit when dynamic groups (continuous mixing) are required. Broad sorting efforts are still helpful in these systems to accommodate feeding regimens and animal temperaments.

Very large groups increase other challenges, as well. Observing individual sows is difficult, which can complicate breeding, vaccinations, heat checking and individual feed intake. This is where trickle feeding or electronic sow feeders offer benefits. 

Another consideration for group housing, regardless of the group size, is the need to minimize stress on the sow before and after mating to accommodate its reproductive performance.

“If we have sows fighting with each other in the three to eight days prior to breeding, it can have a negative impact on reproductive performance,” says Mark Whitney, Extension swine specialist, University of Minnesota. “Also, the period beginning 10 to 14 days after breeding until about four weeks after breeding is the most sensitive period to ensure that the sow is not stressed. Any mixing, handling or fighting stress on the sow at that time can significantly reduce the number of viable embryos.”     

“Sows are most sensitive to stress from mating to about 30 days after,” Safranski agrees. “If we can avoid stressing sows from group housing systems during that period, it adds value.” After that, sows can still maintain pregnancy through stress situations, such as fighting. Placing sows in crates during this critical 30-day period is a wise option.

“If possible, we should avoid mixing sows right after weaning, during breeding or immediately after breeding,” Whitney says. “If we must group sows, we need to try to have smaller groups where the animals are similar in weight and parity to help minimize the competition and fighting that occurs.”

In Europe, producers often combine both housing types. Groups are used post-weaning to help induce sows to cycle, and to identify and sort those in heat. Sows ready for mating move to the boar area. After mating, they remain in a stall for 30 days before returning to the group setting.

Regardless of the housing type, attention to detail is the key, Safranski says. “I don’t care what kind of housing system it is, you’ve got to do things right.”