370 likes | 544 Views
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. Advantages of stall housing. Feed intake Decreased aggression Individual health check.
E N D
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
Advantages of stall housing • Feed intake • Decreased aggression • Individual health check
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
Pen Distribution and Feeding Station Feeding Station
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
Objective • To assess the welfare of gestating sows in large groups on deep-litter compared to individual stalls.
Experimental Design • Experiment 1: • 640 Sows • Two treatments • Conventional stalls (320 sows) • Large groups on deep litter (320 sows)
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
Measurements • Injuries and locomotion
Assessments • Injuries at weaning and weeks 1, 9 and 15 of gestation • Scratches • Abrasions • Cuts
Results Number of scratches was higher in large groups P<0.001 P<0.001 P<0.001
Results Number of abrasions was higher in Stalls P<0.001
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?
Assessments • Weaning previous to treatment • Week 9 and 15 of gestation • Stalls: allowed to walk 30 m before assessment • Large groups: after feeding
Results Locomotion better in Large groups P=0.001 P=0.001
Results Less severe locomotion problems in Large groups Sows scoring 2 or 3 P<0.001 P<0.001
Results Lower culling rate in Large groups
Measurements • Behaviour • Feeding behaviour • Occurrence of aggression • Time budget
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
Results Aggression decreased between week 1 and 9 P<0.05
Results Time budget Percentage of time spent lying or standing/walking P<0.002 P<0.005
Measurements • Physiological measurements • Salivary cortisol • weeks 1 and 9 of gestation • Immunology • Week 16 of gestation • Haematology • Lymphocyte sub-populations
Results Saliva cortisol
Results P<0.05 P<0.05 Immunology
Results Immunology: Neutrophil/Lymphocyte ratio P<0.05
Measurements • Reproductive performance
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
Results Farrowing rate
Results Individual productivity P=0.01
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
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
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
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
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 • R&D staff at QAF Meat Industries