Animal breeding: a neglected factor in animal welfare. Anna Valros Professor of Animal Welfare

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1 Animal breeding: a neglected factor in animal welfare Anna Valros Professor of Animal Welfare

2 Contents Domestication Animal welfare Resource allocation theory Examples of negative side effects of breeding for production Breeding and behaviour Discussion points

3 Evolution vs domestication 4600 m.yrs Earth forms Life begins Mammals evolve 60 m.yrs Horse-like animals Domestication Horse Human Dog? Sheep Pig Chicken Cattle Eläinlääketieteellinen tiedekunta / Anna Valros Horse animal breeding

4 What is domestication? that process by which a population of animals becomes adapted to man and to the captive environment by genetic changes occurring over generations and environmentally induced developmental events reoccurring during each generation (Price, 1984) Eläinlääketieteellinen tiedekunta / Anna Valros

5 Effects of domestication Reduction of fear Changes in colour Changes in size Changes in fat storage Smaller brain and head, weaker senses Eläinlääketieteellinen tiedekunta / Anna Valros

6 Domestication and behaviour Behavioural changes slower than physiological changes Changes are mainly quantitavive, not qualitative Eläinlääketieteellinen tiedekunta / Anna Valros

7 What is animal welfare? Eläinlääketieteellinen tiedekunta / Anna Valros

8 Health vs welfare Animal health Pathological changes and adaptations to these Animal welfare The balance between the behavioural and physiological needs of an animals and its environment -> The animals perception Eläinlääketieteellinen tiedekunta / Anna Valros Broom,

9 Animal welfare Very low level of animal welfare Very high level of animal welfare Positive negative situations Life not worth living Life worth living Good life Legal minimum? Eläinlääketieteellinen tiedekunta / Anna Valros Broom,

10 Five freedoms (FAWC, 1993) 1. Freedom from thirst, hunger and malnutrition 2. Freedom from discomfort 3. Freedom form pain, injuries and illness 4. Freedom to express behavioural needs 5. Freedom from fear and anxiety FAWC: Farm Animal Welfare Council

11 Eläinlääketieteellinen tiedekunta / Anna Valros

12 eellinen tiedekunta / Anna Valros Hits according to keywords Search terms Hits Animal welfare (AW) AW and behaviour AW and transport AW and housing 8271 AW and selection

13 Resource allocation theory An animal has only a limited amount of resources available When more and more resources are allocated to production, less are available for eg. immune defence, behaviour, coping, stress tolerance (Beilharz, Rauw) Eg. layng hens bred for high production are less active and feed more intensively than Bantham and Jungle fowl (Schutz & Jensen, 2001) Resources can only be increased to a certain limit (eg. feed intake limits nutritional resources)

14 Examples of negative side effects of breeding

15 In Denmark piglets per day die of hunger Yle Mass death of piglets stirs up feelings in Denmark: Greed kills per day Uusisuomi

16 Piglet mortality Piglets / litter Total born Born alive Weaned Sold Year Evolution of litter size in French sow herds (IFIP-Institut du Porc, National GTTT data bank). Boulot, et al.,

17 Boulot, et al., 2008 Litter size (class) Mean parity Litter N No. total born No. born alive No. stillborn Mean BW, kg 1.89 a 1.67 b 1.57 c 1.47 d 1.38 e CV BW, % 14.9 d 17.4 c 20.2 b 21.3 b 23.7 a Distribution in BW classes, % < 1.0 kg 3 e 5 d 8 c 10 b 15 a kg 8 e 16 d 21 c 29 b 34 a kg 27 c 39 b 43 a 43 a 38 b > 1.8 kg 63 a 40 b 28 c 19d 13 e a,b,c,d,e Within each row, means with no common superscript differ (P < 0.05)

18 Poultry Broilers and turkeys are the most extreme example of selection for rapid growth and efficient feed conversion ratio - DWG of broilers: 1956: 21 g, 2010: 63 g There is evidence that the selection has caused severe changes in the birds physiology, causing eg. changes in the hypothalamic satiety response (Burkhart et al, 1983) The selection for high growth rate has probably also reduced the immune function in broilers and turkeys as well as increased mortality rates

19 Broiler breeders Due to huge increases in growth potential, broiler breeders must be severely feed restricted - ad libitum fed broiler breeders had a mortality of 40% by 40 weeks (compared to 6% in restricted (Heck et al 2004) - Over-feeding also leeds to poor fertility (Hocking, 2009) and leg problems (Mench, 2002) - Feed is consumed in about 15 min During rearing, radical feed restriction (25-33%) is necessary to decrease welfare problems - Feeding programs usually include 1-3 no-feed-days per week During the laying phase feed is restricted to 45-80% in females At 39 d a Ross 208 broiler breeder female weighs 615 g and an ad libitum fed broiler female 2,2 kg

20 Consequences of feed resriction Chronic hunger Aggression around feeding time Abnormal behaviour due to frustration, esp during rearing period Over-drinking (causing need to restrict water availability) Increased redirected and stereotypic pecking Increased pacing Physiological stress responses Elevated plasma cortisol Changes in immunofunction Increased fibre content in feed might have an effect, but it is not very clear - Even though the gut might be fuller, metabolic hunger remains

21 Broilers Continued genetic selection for fast growth has a negative effect on leg problems, a major part is heritable (Whitehead et al, 2003) A large number of broilers have impaired walking and experience pain and discomfort Slow-growing broiler breeds have better walking ability (Middlekoop et al (2002) European studies show prevalence of leg weakness to be between 0,4 and 32,6% (EFSA, 2010) In a UK study of bords, 27,6% scored 3-5 (Knowles et al, 2008)

22 Broilers cont. Ascites / sudden death syndrome (SDS) are the most common causes of death in healthy flocks Both are caused by a combination of selection for fast growth, feeding and managament There is a genetic correlation between growth and ascites and growth and SDS (Deeb et al 2002, Moghadam et al 2005) High growth is also correlated to lower general activity

23 Dairy cows The milk yield of dairy cows has increased dramatically during the last 40 years, and is now about 10 times that of beef cattle Both management and genetics have been important, genetics especially after the 1980s Unfavourable genetic correlations between high milk yield and ketosis, mastitis, lameness, fertility problems and reduced oestrus behaviour (Oltenacu and Broom, 2010)

24 The high production causes metabolic stress: cows can not eat enough to prevent metabolisation of reserves Increased need for nutrients can cause time contstraints (especially in automatic milking systems) and eg. reduced time for resting

25 Increased size of dairy cows causes welfare problems due to barn buildings becoming too small High producing dairy cows are extremely dependent on proper management and sensitive to disturbances - Problems eg in grazing countries and organic production

26 Breeding for behavioural traits Should we breed the animal to fit the environment or the other way around? Examples: - we can not anticipate the possible risks - breeding for zombies might decrease suffering, but what about pleasure? And what about animal integrity? -Maternal abilities in sows -Feather pecking in hens -Tail biting in pigs

27 Social effects By selecting animals on their performance as a group, social effects are accounted for Muir (1996) selected against mortality dur to feather pecking: from 68% in generation 2 to 9 % in generation 6 Ellen et al (2007) slected for egg production and low mortality: 20 vs 30% mortality in the first generation Selection for high social breeding value for growth in pigs altered their aggressive behaviour (de Vries unpublished, see Rodenburg et al 2010)

28 Discussion points Breeding in optimal conditions: - animals in real life do not get the same resources > risk for welfare problems More information is needed on long-term economical efficiency (eg. milk yield and mastitis)

29 To conclude Breeding decisions have a major influence on the welfare of production animals A larger focus on health and welfare is needed in breeding programs: Breeding companies have a great responsibility for the future welfare of our production animals. Need for societal discussions on the ethical limits for breeding

30 Thank you!