Agriculture Reference
In-Depth Information
3.3.2
Electronic sow feeding
In ESF systems sows are kept in groups of 40 to 500 with one feeder per 40-60 sows.
Upon entering the feeder, sows are identified by a transponder inserted in an ear button.
Sows can eat their daily ration in one meal, and 95% of the sows do so. Once a sow has
finished her daily ration she has no access to the feeder trough anymore, so that the sows
lower in rank then get the opportunity to eat. Each sow needs 15 to 20 min to finish her
meal, depending on parity and amount of feed. Theoretically, 72 animals could therefore
be fed by one feeder. However, as revisits by dominant sows may occur and even the
most reliable systems have occasional break downs it is advisable not to overstock. For
the same reasons group sizes are often multiplied to make it economically viable to have
more than one feeder in a pen. A limited amount of water is provided with the feed in the
feeder and water is freely available elsewhere in the activity area. It's a good thing if there
is a period of inactivity in the group, both for the animals, but also for the stockman to
do some inspection, maintenance or training.
The lying space required per sow may be a little less compared with other systems. Because
sows have a lot of physical contact during lying under thermoneutral conditions they
need 0.5 m wide × 2.0 m long or 1 m
2
lying area. In bedded systems this is approximately
1.3 m
2
. The lying area in non-bedded systems is often divided in lying areas for 8-10
sows with low partitions to support the lying behaviour and a 2% slope in the direction
of the slatted floor. In bedded systems, larger lying areas without obstacles are used. The
common commercial systems use 1.0 to 2.5 m
2
for activities as eating and dunging, so
the total space allowance per sow is 2.0-2.5 m
2
(Figure 3.2 and 3.3).
The group composition can be static or dynamic. In static groups all sows are mated in
the same week and grouped several days after service or 3-4 weeks after service. Group
composition does not change during pregnancy, however, those sows returning to oestrus
Figure 3.2. Electronic sow feeding in a group of 150 sows on concrete solid and slatted floors without bedding.
