Animal Welfare Assessment and Challenges Applicable to Pregnant Sow Housing Gail C. Golab, PhD, DVM, MANZCVS, DACAW Director, Animal Welfare Division
To Cover How AVMA approaches animal welfare issues in general 2005 Report Task Force on the Housing of Pregnant Sows Current recommendations based on that report Future plans Food for thought
Evaluating an Animal s Welfare BODY MIND Measures of health, growth and productivity NATURE Measures of affective states (suffering, contentment) 3 Quantitative and qualitative comparisons to wild or free-living conspecifics
Being Comprehensive Function Feelings Natural Living
The Five Freedoms One Paradigm for Connecting the Circles The Five Freedoms is one scientific assessment approach that tries to connect circles Freedom from hunger and thirst Freedom from discomfort Freedom from pain, injury and disease Freedom to express normal behavior Freedom from fear and distress Difficult to satisfy all of the freedoms simultaneously because of trade-offs among the features of animal care systems
For Gestating Sows Stalls Pens Outdoors Nutrition + + Discomfort + Injury/Disease + Behavior + + Fear/Distress + +
(Even) Scientific Bias Toward Trade-Offs The consequences for welfare of housing pigs in stalls for varying durations should be evaluated. Because stall housing is a controversial issue from the view of public perception, but may have reproductive and welfare advantages, housing in stalls for a defined period that is considerably less than the period of gestation may be a reasonable compromise There is no scientific evidence to support the recommendation in the Code of Practice advising against housing sows in stalls followed by housing in crates. A Review of the Welfare Issues for Sows and Piglets In Relation to Housing Barnett JL, Hemsworth PH, Cronin GM, et al. Aust J Agric Res 2001;52:1-28. Since overall welfare appears to be better when sows are not confined throughout gestation, sows should be preferably kept in groups. However, only housing systems resulting in minimal aggression or injury should be used.no individual pen should be used which does not allow the sow to turn around easily. The Welfare of Intensively Kept Pigs Report of the Scientific Veterinary Committee, European Commission, September 30, 1997
AVMA s Task Force on Sow Housing Analysis and 2005 Report Not a new discussion conversations dating back to mid-1990s; brought to forefront in 2000-2002 in the AVMA House of Delegates Representatives from multiple disciplines and with varying perspectives Looked at stalls in comparison with group housing ~2000 pages of literature reviewed Using five freedoms as a base, assessed Physiologic function Health measures Behavior Production
Physiologic Function Stress is assessed by measuring Concentrations of hormones circulating in the blood that allow animals to respond effectively to challenging situations Cortisol ß-endorphins Prolactin Prostaglandin F-2α Oxytocin Heart and respiratory rates Immune system responses (blood cell types and concentrations) Overall, physiologic measures of stress are similar for sows housed in stalls and those housed in group pens. Less socially dominant sows raised in group pens had higher stress hormone concentrations Sows housed in stalls that allowed them to turn around had lower cortisol concentrations than sows housed in conventional stalls
Health Measures With the exception of injuries, health of sows is primarily affected by Daily management Exposure to pathogens Geographic location Biosecurity measures taken Injuries qualitatively different by housing type Stalls Pressure sores resulting from contact with bars and less frequent postural changes Group pens Bites and scratches resulting from aggressive interactions between sows In total, fewer injuries in stalls, but rate of injury is substantively affected by how sows are managed in each system (e.g., size of stall, feeding system, mixing, genetics)
Behavior Space and Movement Stereotypical Behavior Social Contact Aggression Control Over Environment Feed Restriction Space and freedom of movement Stalls restrict movement ; when parity is high, sow may outgrow size of stall. Movement restrictions may translate to lameness, reduced muscle tone and mass, reduced agility, reduced bone strength. When high quality feed and water available, sows in all systems are relatively inactive. Stereotypical behavior Sows in all types of housing exhibit oral-nasal-facial behaviors (e.g., chewing or biting enclosures, rooting) Stereotypical behaviors (repetitive behaviors with no obvious purpose) are more common in sows kept in stalls and small, barren pens
Behavior Social contact Sows are social animals and will work for social contact. Individual housing appears to be minimally aversive to sows as long as there is visual and other contact with other pigs Stress can result if neighbors are incompatible (applies to both stalls and groups) Aggression Has been reported in all types of housing, but is often worse in group pens, particularly when unfamiliar animals are mixed. Aggressive interactions can result in severe injuries. Aggression in group pens can be reduced (but often not eliminated) by appropriate system design and management, especially attention to how feed is provided.
Behavior Control over environment and complexity Sows in natural conditions control their interactions with the environment (create feeding, nesting, and defecation areas; seek shelter; wallow). Sows in confinement cannot exercise control (flee aggressive neighbors, choose their social interactions) Pigs react positively to environmental complexity (reduced aggression, varied use of living area, lower cortisol concentrations) Group housing provides some additional self-control, but varies in complexity in what is provided to occupy time Feed restriction Limit-feeding exacerbates the effects of housing because it intensifies competition for food, and makes sows more restless and more motivated to forage.
Behavior Overall Stalls adversely affect welfare by restricting movement and social interactions Aggressive interactions are a challenge in group systems Barren environments can create welfare negatives in any system
Production Estrus detection and weaning-to-estrus interval Estrus in multiparous sows is not affected by housing type Gilts in stalls exhibit more irregular estrus behavior Weaning-to-estrus intervals are shorter for pigs in stalls than in groups Conception and farrowing rates Study results are contradictory and strongly influenced by season and management practices Housing sows in groups increases risk of rebreeding Litter size Unaffected by housing type Overall, sows in stalls appear to have equivalent production performance to sows in groups
AVMA s Recommendations Based on Task Force Report Sow housing systems should Provide every animal access to appropriate food and water Reduce exposure to hazards that result in injuries, pain or disease Protect sows from environmental extremes, and promote good air quality and proper sanitation Facilitate observation of individual sows Allow sows to express normal patterns of behavior Minimize aggression and competition among sows To address animal welfare in the long term, sow housing efforts should follow a model of continuous improvement. Advantages of current housing systems should be retained, while making improvements to overcome problems identified.
What Next? Request to update report Systematic literature review How mixing sows, feeding, and other types of management (including group size) affect the success of group systems Physical impacts of both stalls and group systems (e.g., lameness, injury) More detailed look at productivity parameters Genetics Visual translation to assist in evaluation and improve understanding
Food for Thought Trade-offs among housing systems Intensive Systems Extensive Systems Physical Indicators of Welfare and Efficiency Behavioral Indicators of Welfare and Naturalness
Food for Thought Individual housing versus stalls Welfare benefits associated with stalls largely accrue from individual housing, not from stall configuration (2 x7 ) Stall configuration driven by economics Efficient use of space Labor costs and safety Economics important consideration Large capital investment in existing operations Feasibility of conversion (capital costs impacted by timeline) Resources for animal care
Food for Thought Science informs decisions, but people make them Issues confronted across species give us information about what raises public concern Boxes and restraints Cutting things off, other modifications; especially if painful and without anesthesia Death (what, why, when and how) Society sets boundaries as to what is acceptable and/or preferred Lots of factors come into play?
Thank You for Your Time and Attention Corrected Contact Information: Division of Animal Welfare American Veterinary Medical Assn 1931 North Meacham Rd, Suite 100 Schaumburg, IL 60173 (847) 285-6618 (direct) (847) 925-9329 (fax) ggolab@avma.org