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

2. 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

4. Large group housing

5. Large group housing

6. Pen Distribution and Feeding Station

7. 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

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

9. Experimental Design Experiment 1: 640 Sows Two treatments
Conventional stalls (320 sows)
Large groups on deep litter (320 sows)

10. 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

11. Measurements
Injuries and locomotion

12. Injuries at weaning and weeks 1, 9 and 15 of gestation
Assessments
Injuries at weaning and weeks 1, 9 and 15 of gestation
Scratches
Abrasions
Cuts

13. Injury assessment

14. Number of scratches was higher in large groups
Results
P<0.001
P<0.001
P<0.001
Number of scratches was higher in large groups

15. Number of abrasions was higher in Stalls
Results
P<0.001
Number of abrasions was higher in Stalls

16. 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?

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

18. Locomotion better in Large groups
Results
P=0.001
P=0.001
Locomotion better in Large groups

19. Less severe locomotion problems in Large groups
Results
Sows scoring 2 or 3
P<0.001
P<0.001
Less severe locomotion problems in Large groups

20. Lower culling rate in Large groups
Results
Lower culling rate in Large groups

21. Measurements Behaviour Feeding behaviour Occurrence of aggression
Time budget

22. 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

23. Aggression decreased between week 1 and 9
Results
P<0.05
Aggression decreased between week 1 and 9

24. Results Time budget Percentage of time spent lying or standing/walking

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

26. Results
Saliva cortisol

27. Results
P<0.05
P<0.05
Immunology

28. Immunology: Neutrophil/Lymphocyte ratio
Results
P<0.05
Immunology: Neutrophil/Lymphocyte ratio

29. Measurements
Reproductive performance

30. 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

31. Results
Farrowing rate

32. Individual productivity
Results
P=0.01
Individual productivity

33. 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

34. 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

35. 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

36. Experiment 2 Three treatments 1080 sows 14 months of data collection
Stalls (15 weeks)
Large groups (15 weeks)
5 weeks in stalls and 10 weeks in large groups
1080 sows
14 months of data collection

37. Acknowledgments Funding provided by: Supervision: Special thanks to:
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
R&D staff at QAF Meat Industries