Objective—To determine whether there is a relationship
between sow injuries and size of gestation stalls
relative to sow size.
Animals—267 pregnant sows.
Procedure—Sows were randomly selected from 4
swine farms. Sow and stall measurements were
obtained, and injuries were scored on the basis of location,
number, and depth. Ratios of stall length to sow
length and stall width to sow height were calculated.
Results—High injury scores were associated with
low ratios of stall length to sow length and stall width
to sow height.
Conclusions and Clinical Relevance—A small increase
in stall dimensions could reduce injuries and improve
well-being of sows considerably. (J Am Vet Med Assoc
Objective—To analyze the association of lameness and performance variables on sow longevity by use of time-to-event analysis.
Animals—674 sows from a commercial breeding herd.
Procedures—A lameness assessment was performed on each sow. Data on farrowing performance and longevity were collected for the sows during 3 or fewer parities from the database of the herd during 2005 and 2006. The association of risk factors with sow longevity within 350 days after lameness assessment was analyzed via Cox regression analysis. Pigs per day, total production days, and survival at 350 days after lameness evaluation were compared between lame and nonlame sows.
Results—Numbers of preweaning baby pig deaths, stillborn pigs, and mummified pigs were negatively associated with sow longevity within 350 days after lameness assessment. A higher number of pigs born alive and younger parity of sows were protective. Lame sows had a higher risk (1.710 times as high) of removal from the herd within 350 days after lameness assessment. The number of pigs born alive per day, survival of sows at 350 days, and total number of days in the herd were lower in lame sows.
Conclusions and Clinical Relevance—Results of this study indicated significant differences in the survivability of lame and nonlame sows in a commercial herd. Parity and farrowing performance variables were factors influencing sow longevity in this herd. Producers need to minimize sow lameness and remove lame sows from a herd early (when treatment is not an option) to minimize economic loss.
Objective—To characterize pattens of removal and
evaluate the associations among culling because of
lameness and sow productivity traits among culled
gilts and sows.
Sample Population—Data from a convenience sample
of 11 farms pertaining to the removal of 51,795
gilts and sows from January 1991 to December 2002.
Mean culling and mortality (death and euthanasia)
rates for all inventoried gilts and sows ranged from
23% to 50% and 4.7% to 9.5%, respectively.
Procedure—An analysis of categories of removal
(cull, death, or euthanasia) and reasons for removal of
gilts and sows was performed. Multivariate logistic
regression was used to determine associations
among culling because of lameness and sow productivity
traits among culled gilts and sows.
Results—Among sows that were removed, the proportion
of parity ≥ 1 sows that died (both death and
euthanasia) was > 3 times the proportion of parity ≥ 1
sows that were culled within 20 days after farrowing.
Among lame sows that were removed, the proportion
of parity ≥ 1 sows that died (death and euthanasia)
was higher than the proportion of parity ≥ 1 sows that
were culled within 20 days after farrowing. Among
sows that were removed, the proportion of sows that
died (deaths and euthanasia) was higher during lactation
than nonlactation. This was also observed among
lame sows that were removed.
Conclusions and Clinical Relevance—The proportion
of death among removed sows, especially lame
sows, was higher during lactation than nonlactation.
Results indicated that risk of death is not the same for
sows throughout their lifetime. (J Am Vet Med Assoc
Objective—To compare well-being, performance,
and longevity of gestating sows housed in stalls or in
pens with an electronic sow feeder (ESF).
Animals—382 pregnant sows of parities 1 through 6.
Procedure—Sows were housed in separate stalls
(n = 176) or group pens (206) with an ESF. Well-being
of sows was assessed at various time points in terms
of injuries, salivary cortisol concentration, and behavior
in a novel arena or to a novel object. Farrowing performance
and longevity of sows were also assessed.
Results—Total injury scores (TIS) of sows in pens
were significantly higher at initial introduction and
mixing. In stall-housed sows, TIS was significantly
higher during late gestation. The TIS and cortisol concentration
were significantly lower in stall-housed
sows, compared with values for sows in pens. As parity
increased, the likelihood of higher median TIS
decreased significantly in pen-housed sows and
increased significantly in stall-housed sows. The TIS
of sows in pens was negatively correlated with body
weight and backfat thickness, whereas these correlations
were positive in stall-housed sows. Farrowing
performance and results for novel arena or objects did
not differ. Proportion of sows removed was significantly
higher for pens than for stalls; lameness was
the major reason for removal for both systems.
Conclusions and Clinical Relevance—Stalls impose
space restrictions for larger sows, resulting in injuries
during late gestation. Interventions are needed to
minimize aggression during initial introduction and
mixing and at the ESF in pens to reduce severe
injuries or lameness of gestating sows. (Am J Vet Res