The Rural Voice, 2006-06, Page 26One size
doesn't fit all
Prairie Swine Centre
researchers say it's
important to have
different -sized sow stalls
for different -sized sows
By Keith Roulston
The use of gestation stalls has
been controversial in some
quarters but using the right
size of stalls for the right size of
animals could improve sow comfort,
say researchers at the Prairie Swine
Centre, Inc. (PSC) in Saskatoon.
In a written presentation delivered
at the 25th annual Centralia Swine
Research Update at Kirkton in
January, Y. Z. Li and Dr. Harold
Gonyou wrote that producers can
improve the longevity of breeding
sows by varying the width of stalls.
Dr. Gonyou says that in an effort
to maximize the economic efficiency
of hog production facilities, the
industry has been driven
to narrower and
narrower gestation stalls.
He argues that while this
has been cost effective,
the industry is
recognizing that one size
does not fit all when it
comes to sows.
The PSC researchers
point out that generally a
farm has only one size of
sow stall, but there is a
wide range of body
weights among sows,
ranging from gilts to
large, mature sows, with
weights from 150 to 350
kg. While the Code of Practice
suggests producers use different sizes
of stalls for different sizes of sows,
there's never been a clear definition
of what the proper width of stall is
for each animal, they say.
The researchers recorded sows of
various sizes (145, 180, 216 and 259
kg. respectively, post breeding
weight) and followed them during
gestation. The animals typically
gained 60-80 kg during pregnancy.
Li and Gonyou recorded the
amount of time spend standing
versus lying and the amount of time
in which the udder of the sow
extended into the adjoining stall.
The found the problem of the udder
extending into the next stall was
significantly affected by the
interaction of stall width and the
we suggests that a 55 cm stall is
suitable for gilts and small sows, a
60 -cm stall for medium sows, and a
65 -cm stall for large sows during the
early stage of gestation (to week
four), as would be the case if sows
were moved into group housing after
implantation. But in later stages
•(week 14), gilts and small sows
should behoused in 65 cm, and
larger sows in 70 cm stalls.
"Pork producers should use a
variety. of stall widths to
accommodate various -sized gestating
sows. If stalls are used for the entire
gestation period, 65 cm stalls appear
to provide adequate space for gilts
and small -sized sows, and
70 cm stalls for larger
sows," the researchers
wrote.
"When (sows) come
from farrowing and go into
the breeding/gestation
unit, you move all you
small animals first into the
small stalls," Gonyou
suggests, "so that your
biggest sows have access
to the biggest stalls."
While it's all well and
good for Li and Gonyou to
make recommendations,
getting people to actually
change their stalls and
their habits can be a different matter.
Cost, space and inertia can mean
action is unlikely.
But if producers don't take action,
Gonyou's findings may find become
"Pork producers should use a varlet!' of
stall widths to accommodate various -
sized gestating sows. If stalls are used
for the entire gestation period, 65 cm
stalls appear to provide adequate space
for gilts and small -sized sows, and 70
cm stalls for larger sows," the
researchers wrote.
22 THE RURAL VOICE
sow's size.
"Using the criteria that the udder
should not extend into the adjoining
stall more than 50 per cent of the
time that the sow is lying on her side,