The Welfare of Gestating Sows in Conventional Stalls and in Large Groups on Deep-litter

1
The Welfare of Gestating Sows in Conventional
Stalls and in Large Groups on Deep-litter

• Guillermo Karlen
• Animal Welfare Science Centre
• Department of Primary Industries, Victoria
• University of Melbourne

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Advantages of stall housing

• Feed intake
• Decreased aggression
• Individual health check

3
Welfare concerns

• sows are unable to exercise
• sows have limited social interaction
• sows show signs of chronic stress (in some
  studies)
• Use of stalls for gestating sows have been
  restricted in EU and banned in some countries

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Large group housing
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Large group housing
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Pen Distribution and Feeding Station
Feeding Station
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Welfare in groups

• Advantages
• are able to exercise
• have social interaction
• less feed needed to maintain body condition
• avoid aggression
• Disadvantages
• increased aggression
• retaliation
• more animals
• feed intake control

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Objective

• To assess the welfare of gestating sows in large
  groups on deep-litter compared to individual
  stalls.

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Experimental Design

• Experiment 1
• 640 Sows
• Two treatments
• Conventional stalls (320 sows)
• Large groups on deep litter (320 sows)

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Experimental Design

• Large groups each replicate
• 40 experimental 45 non-experimental
• N 85 sows in 1 pen
• Space allowance 2.3 m2 per sow
• Stalls each replicate
• 40 individually housed sows
• Eight replicates of each treatment
• Weekly allocation of replicates
• 18 focal sows per replicate in each treatment
• 6 from each parity group
• Data collection 27 weeks

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Measurements

• Injuries and locomotion

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Assessments

• Injuries at weaning and weeks 1, 9 and 15 of
  gestation
• Scratches
• Abrasions
• Cuts

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Injury assessment
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Number of scratches was higher in large groups
Results
Plt0.001
Plt0.001
Plt0.001
15
Number of abrasions was higher in Stalls
Results
Plt0.001
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Measurements

• Locomotion score
• Sows were scored when standing, walking and
  trotting on a concrete pathway.
• 0 sound
• 1 difficulties putting weight on one or more
  limbs
• 2 locomotion is obviously altered signs of pain
• 3 unable to walk, severe pain?

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Assessments

• Weaning previous to treatment
• Week 9 and 15 of gestation
• Stalls allowed to walk 30 m before assessment
• Large groups after feeding

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Locomotion better in Large groups
Results
P0.001
P0.001
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Less severe locomotion problems in Large groups
Results
Sows scoring 2 or 3
Plt0.001
Plt0.001
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Lower culling rate in Large groups
Results
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Measurements

• Behaviour
• Feeding behaviour
• Occurrence of aggression
• Time budget

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Assessments

• Week 1 and 9 of gestation
• Feeding behaviour feeding speed
• Occurrence of aggression 4 x 10 minutes of
  continuous observation
• Time budget instantaneous scanning every 5
  minutes for 40 minutes

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Aggression decreased between week 1 and 9
Results
Plt0.05
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Time budget
Results
Percentage of time spent lying or standing/walking
Plt0.002
Plt0.005
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Measurements

• Physiological measurements
• Salivary cortisol
• weeks 1 and 9 of gestation
• Immunology
• Week 16 of gestation
• Haematology
• Lymphocyte sub-populations

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Saliva cortisol
Results
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Results
Plt0.05
Plt0.05
Immunology
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Immunology Neutrophil/Lymphocyte ratio
Results
Plt0.05
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Measurements

• Reproductive performance

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Assessments

• Farrowing rate
• Total born
• Born alive
• Stillborn
• Mummies
• Average piglet birth weight
• Average piglet weaning weight
• Total litter (alive) birth weight
• Total litter weaning weight

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Farrowing rate
Results
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Individual productivity
Results
P0.01
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Summary

• Early in gestation
• Higher incidence of scratches in Large groups
• Lower incidence of abrasions in Large groups
• Higher salivary cortisol concentration in Large
  groups
• The locomotion problems were less severe in Large
  groups

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Summary

• Late in gestation
• Higher incidence of scratches in Large groups,
  although the number decreased substantially
• Lower incidence of abrasions in Large groups
• The locomotion problems increased in Stalls
• Lower immune response in Stalls

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Conclusion

• Sows in Large groups faced higher challenges
  early in gestation, however they seem to decrease
  over time
• In contrast, Sows in stalls faced increasing
  challenges later in gestation
• Different systems have different problems
• Design is more important than the system per se

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Experiment 2

• Three treatments
• Stalls (15 weeks)
• Large groups (15 weeks)
• 5 weeks in stalls and 10 weeks in large groups
• 1080 sows
• 14 months of data collection

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Acknowledgments

• Funding provided by
• Department of Primary Industries Victoria
• Australian Pork Limited
• The University of Melbourne
• Supervision
• Prof. Paul Hemsworth (The University of
  Melbourne, Australia) and
• Dr Harold Gonyou (Prairie Swine Centre,
  Saskatchewan, Canada)
• Special thanks to
• Dr John Barnett
• Dr Greg Cronin
• Dr Emma Fabrega
• AWSC staff and students
• RD staff at QAF Meat Industries