Agriculture Reference
In-Depth Information
3.3.1
Free access stalls
In Free Access Stall (FAS) systems sows are typically kept in groups of 8 to 40 per pen.
One pen consists of one or two rows of lockable feeding stalls with a communal slatted
indoor run behind the stalls (Figure 3.1). A double row of stalls is preferred offering the
sows more space between the rows for dunging, drinking, exploration and social contact.
Sows are fed once or twice a day and are locked during feeding for 30 minutes, until their
health and feed intake is checked. A limited amount of water can be provided in the
feeding trough to stimulate feed intake, and water is available freely in the indoor run.
Group size is variable by adjustable fences between the pens. Normally, groups of sows
mated in the same week are sorted according to age and body condition, because they
are fed a group level and not an individual level. Because the sows cannot make physical
contact during lying, the lower critical temperature is 18 °C. This means that below 18 °C,
the sows need extra feed to maintain body condition.
Every sow has her own 65-70 cm wide and 200 cm long stall with fully solid floor, which
also serves as lying area. The width of the indoor run is at least 300 cm to give sows the
space to move around freely and to lower the risk on skin lesions and lameness caused
by aggression. A feeding/inspection alley in front of the stalls is valuable for inspection,
adjustment of feeders and ventilation. However, in case of conversion from individual
housing to group housing the existing feeding alley is often used to create more space
between the stalls and to have more solid floor in the stalls.
Sows can be kept in this system from several days after service or from positive pregnancy
test until one week before expected farrowing, at which time they are moved to the
farrowing pen. There are free access stall systems with a separate lying area (with or
without bedding or kennels), but they require more space than when the feeding and
lying areas are combined in the stalls.
Figure 3.1. Free access stalls with a wide slatted area between two rows of stalls.
