Practicality and Payback

Group gestation barns are a quiet, pleasant environment for sows and employees. They are often cheaper to build than traditional stall barns because there are no stalls, feed troughs or complex gutter and floor designs. Per-square-foot costs vary by region, however.

Naturally, the cost of a group gestation housing system also varies with design, square footage per sow, complexity of the pen, feeding method and amount of slotted area.

A recent review of building costs in Ontario showed that a group gestation barn with a pen structure, an automatic-multiple-drop feeding system and 25 sq. ft./sow costs about the same as a stalled barn.

Producers that feed group-housed sows several times a day report that sows are calmer than sows fed once a day.

However, even with perfect pen design and feeding techniques, an overly aggressive or shy sow will occasionally prove incompatible with the group. These sows must be relocated in a small pen for the duration of their gestation period.

Breeding Stalls Needed

Producers using the various group-housing designs commonly wean sows into breeding stalls to prevent them from injuring themselves or others as they demonstrate normal estrus behavior.

Time spent in breeding stalls varies. Some producers mix sows in pens immediately after breeding, while others keep the sows in stalls until they have been confirmed pregnant at about 35 days postbreeding.

If the gestation pens are well designed and managed, sows can be mixed immediately after breeding with little fear of aggressive encounters decreasing reproductive performance. Pregnancy testing in group housing is usually conducted during feeding time.

The various gestation housing designs and management systems discussed here were developed by Ontario pork producers through trial and error until they had limited or eliminated aggression between sows. The success of these systems has been evaluated in a number of ways:

1. The sows have fewer scratches, injuries and lameness, and their body condition remains consistent.

2. Farrowing rates are greater than 80%, with a few approaching 90%.

3. Producers rarely have to remove a sow that is not doing well in the group.

4. Some producers find that group sow housing barns are quieter and more pleasant to work in than stall gestation housing.

Questions regarding group housing or converting a conventional stall barn to group pens may be addressed to Kathy.zurbrigg@ontario.ca.