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Agricultural Animal Welfare. Does Agriculture improve the welfare of animals…?. …or cause unnecessary suffering?. This is not a question asked by many people of the world. “A chicken in every pot, every Sunday!”. General Concerns (all species). Decreasing Genetic Variability.
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General Concerns(all species) • Decreasing Genetic Variability
Over 95% of Dairy cows in the U.S. are Holsteins, yet there are hundreds of breeds representing a broader range of genetics
19 breeds just on BRITISH watch list (Rare Breeds Survival Trust)
145 British breeds of sheep (22 on Watch list) Rambouillet Predominant In U.S.
Muscovy Duck Lack of genetic diversity occurs in many species, including chickens, ducks, cattle, and sheep (and is potentially dangerous - recall Irish potato famine).
General Concerns (all species) • Decreasing Genetic Variability • Selection for Single Trait
Selection pressure is often specific to one trait which can create problems in other areas.
~ Selection for lean pigs with low fat content led to pigs with nervous and high strung temperaments. ~ Chickens with extra large breasts grew so fast they developed arthritis and deformed legs. Grandin & Johnson 2005
Also, breeds are not always suited for their environment: Hereford cattle in hot, humid south, for example.
General Concerns (all Ag species) • Decreasing Genetic Variability • Selection for Single Traits • Dystocia
Parturition problems can be the cause of severe suffering in individual animals
Causes of Dystocia ~ Selection for large offspring in meat breeds ~ Stress ~ Age (less a problem on large operations)
General Concerns (all Ag species) • Decreasing Genetic Variability • Selection for Single Traits • Dystocia • Transport
General Concerns (all Ag species) • Decreasing Genetic Variability • Selection for Single Traits • Dystocia • Transport • Slaughter Humane Slaughter Act (USDA enforced) Meat Institute’s Good Mgt Practices for Animal Handling & Stunning
Humane Slaughter Act ~ Passed 1978, enforced by USDA ~ All animals must be dead or stunned before “painful practice” ~ # inspectors decreasing, USDA no longer tracks violations.
Other concerns about the implementation of the Humane Slaughter Act: • PROCESSING SPEED (~ In US, remove hooves from 309/hour, or 5 animals a minute or 3 seconds a hoof). ~ Much slower in Europe (EU days)
More guidelines from industry: Meat Institute’s Good Management Practices for Animal Handling and Stunning
Improvements in Welfare in Processing Plants A la Temple Grandin and McDonald’s (1999)
Industry Wide Changes (Cattle) 1996 2002 2004 % Killed when first stunned
Sheep • Most “natural” life, though protected from disease & predation (to an extent) • Most on pasture whole life, some lambs go to “finishing pens” for last month
Sheep Welfare Concerns6.35 million head in 2003(56 mil in 1942) • Predation
Sheep Welfare Concerns • Predation • Dystocia
Sheep Welfare Concerns • Predation • Dystocia • Stress/ pain of vaccinating, tagging, docking & castration
Sheep Welfare Concerns • Predation • Dystocia • Stress/ pain of vaccinating, tagging, docking & castration • Shearing? • Transport and slaughter
Beef Cattle • Most of life on pasture (approx 1.5 years) • “Finished” in feedlots, high protein corn diet • 35 million breeding cows in U.S. • 1.3 billion in world
Beef Cattle Welfare Concerns • Castration
Beef Cattle Welfare Concerns • Castration • Transport & Slaughter
Beef Cattle Welfare Concerns • Castration • Transport & Slaughter • Time in feed lot: odor, access to shade, food & additives
Dairy Cattle Welfare Concerns9.4 million in U.S. Dystocia Mastitis
Dairy Cattle Welfare Concerns Dystocia Mastitis Housing Veal calves (culled males)
Dairy Cattle Welfare Concerns Dystocia Mastitis Housing Veal calves (culled males) Female calves taken away Tail Docking Transport/slaughter when culled
Docking increase cleanliness,udder health? Tucker, Fraser and Weary 2001 ~ 223 docked ~ 190 undocked No treatment differences in cleanliness or health Individuals differences significant ~
Choice Experiment re Handling Pajor, Rushen and Passille 2003 ~ Choice in Y-maze between: ~ Shouting Handler ~ Cattle Prod ~ Tail twist ~ Pail Feeding ~ No difference between shout vs cattle prod; tail twist not aversive
Poultry Welfare: Egg producers • Male chicks
Poultry Welfare: Egg producers Battery Cages banned in EU by 2012 Stocking density = 5 hens/18” by 20”
Poultry Welfare: Egg producers • Male chicks • Battery Cages • Cost of building vs. labor ($$$ in US)
Average consumption per capita = 254 eggs/year (402/yr in 1945)~ 6.45 billion table eggs produced in 2004 ~ 64 companies with over 1 million layers each, 11 companies with over 5 million layers each~ Total of 283 million hens in 2004
Behavioral Observations & Welfare University of Guelph, Ian Duncan” 2006 ~ How hard laying eggs “work” to reach a nest box? ~ Asked to push against weighted door to get to nest box. ~ Use same force, for same duration As if food deprived for 30 hours.
Poultry Welfare: Broilers/ fryers23 million/year • Aggression/ debeaking • “Free range” • Selection for rapid growth - Satiety Center
Broiler/fryers grow up to 22 wks “normal” growth in 5 weeks. ~ Chickens (and turkeys) found to have serious degenerative hip disorders. ~ When administered pain killing meds, turkeys lay down less, walked more, showed more spontaneous activity. Hocking et al. 1999
Consumer Choice Criteria • Cost • Taste (fatter is better) • Convenience • Nutrition/ “wholesomeness” Not ethics/ welfare…