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Donald M. Broom Centre for Animal Welfare and Anthrozoology Department of Veterinary Medicine University of Cambridge, U.K. dmb16@cam.ac.uk . Animal welfare: some current and future issues. Donald M. Broom
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Donald M. Broom Centre for Animal Welfare and Anthrozoology Department of Veterinary Medicine University of Cambridge, U.K. dmb16@cam.ac.uk Animal welfare: some current and future issues Donald M. Broom Centre for Animal Welfare and Anthrozoology Department of Veterinary Medicine University of Cambridge Cambridge CB3 0ES, U.K. dmb16@cam.ac.uk
Animals have always had welfare but what humans know of it has changed. The human concepts of what are and are not moral actions have probably changed little over many millennia. However, ideas about which individuals should be the subject of such actions have changed with : (i) increasing knowledge of the functioning of humans and other animals, (ii) improved communication in the world.
Background theory: 1. Helping others and not harmingothers are effective strategies, especially for animals that live in long-lasting social groups. 2. morality has evolved and religion is a structure for morality (Broom 2003). 3. Attitudes to others have been much affected by the major improvements in communication. 4. Non-human animals are now generally included amongst the individuals about whom we should care.
Moral actions: family - tribe - race - country - world. But also, respect for all people and other living beings, especially animals. View of animals as possessions. This has been the dominant view in laws.
What philosophical positions do people adopt in relation to the treatment of animals and relevant laws? Deontological: some harms should never be done. List of prohibited actions. Effects on people/animals. UK 1876 / 1911 Cruelty to Animals Acts Utilitarian: cost-benefit analysis of human actions. Costs may be to animal itself. Benefit usually human. UK 1986 Animals Scientific Procedures Act
How should we describe what should or should not be done to other individuals? We should describe the obligations of the actor rather than the rights of the subject. We all have obligations not to harm others. If we keep or otherwise interact with animals we then have obligations in relation to their welfare. Assertions of rights and freedoms cause problems.
In recent years, public pressure in relation to codes of practice, laws and the enforcement of laws have increased in all countries concerning: human health, animal welfare, impact on the environment. In Europe, one of the big pressures for laws etc. in these areas has been the view that it is uncivilised to allow people to become sick, animals to be treated badly or the environment to be damaged.
A system or procedure is sustainable if it is acceptable now and if its effects will be acceptable in future, in particular in relation to resource availability, consequences of functioning and morality of action. Animal welfare is one of the criteria used by the public when deciding whether a procedure or system is acceptable so it is a necessary consideration for sustainability. For consumers and producers of animal products, the concept of quality has broadened. Good quality now means good in taste and also sustainable, especially: acceptable in relation to human health, animal welfare and environmental impact. The French ‘Label Rouge’ scheme has led the way in this. The proportion of consumers who buy only on price: down to 25%.
Effects on welfare which can be described include those of: disease, injury, starvation, beneficial stimulation, social interactions, housing conditions, deliberate or accidental ill treatment, human handling, transport, laboratory procedures, various mutilations, veterinary treatment, genetic change by conventional breeding, genetic change by genetic engineering.
Topics of Discussion Animals and response systems are subject to challenges from their environment: pathogens, tissue damage, • State the main ideas you’ll be talking about attack or threat of attack by a conspecific or predator, other social competition, complexity of information processing in a situation where an individual receives excessive stimulation, lack of key stimuli such as a teat for a young mammal or those associated with social contact for a social animal, lack of overall stimulation. In general, inability to control interactions with their environment.
How well can our domestic animals adapt to the conditions that we impose upon them? Can wild animals adapt to our impact on them? At the individual level, adaptation is the use of regulatory systems, with their behavioural and physiological components, to help an individual to cope with its environmental conditions. Animals can adapt better if their needs are met.
What are the limits to adaptation? Where coping means having control of mental and bodily stability, an individual attempting to cope may fail to do so. For example, it may be difficult or impossible to cope with: extreme external temperature, pathogen multiplication, high predation risk or difficult social conditions. Body state may be displaced to outside the tolerable range and death may follow. The term stress is best limited to situations in which control systems are over-taxed and the individual is harmed. Stress implies inability to adapt or to cope. The term stress is scientifically unusable if it includes beneficial stimulation.
An individual may adapt to an environmental situation with difficulty, in which case the welfare is poor. For example, if an individual is adapting, or has adapted, but is in pain or depressed. Coping usually means that all mental and bodily systems have functioned so that the environmental impact is nullified. Hence “to cope” is more than “to adapt”. Adaptation does not necessarily mean good welfare. Similarly, efficient production does not necessarily mean good welfare.
Where the welfare of an individual is its state as regards its attempts to cope with its environment, welfare will be poor if there is difficulty in coping or failure to cope. One or more coping strategies may be used to attempt to cope with a particular challenge. Feelings, such as pain, fear, pleasure, may be part of a coping strategy. The system may operate successfully so that coping is achieved or may be unsuccessful in that the individual is harmed. Welfare can be measured scientifically and varies over a range from very good to very poor.
When coping is successful and problems are absent or minor, welfare is good. Good welfare is generally associated with feelings of pleasure or contentment. Like bad feelings, such as pain or fear, good feelings are a biological mechanism which has evolved. A feeling is a brain construct, involving at least perceptual awareness, which is associated with a life regulating system, is recognisable by the individual when it recurs and may change behaviour or act as a reinforcer in learning. Suffering occurs when one or more negative feelings continue for more than a few seconds.
The brain condition which results in a feeling may have first arisen accidentally but most feelings now occurring are a result of natural selection. Most feelings are important parts of coping systems. • Feelings are an important part of welfare but welfare involves more than • feelings, for example: • an individual with a broken leg but asleep, • an addict who has just taken heroin, • an individual greatly affected by disease but unaware of it, • an injured individual whose pain system does not function.
Which animals should be protected and to what degree should they be protected? For most people, animals with awareness are thought more worthy of protection. A sentient being is one that has some ability: to evaluate the actions of others in relation to itself and third parties, to remember some of its own actions and their consequences, to assess risk, to have some feelings and to have some degree of awareness. However, amongst sentient animals, simpler animals may suffer more than more complex.
People have long appreciated the sentience of various domestic and other animals and have often thought of them as an example to follow or a friend who would help, rather than just as a resource object. However, a rabbit is viewed differently according to whether it is: a family pet, a laboratory animal, an animal kept for meat production, or a wild animal that eats your crops. This is not scientifically sound. A rabbit is a rabbit and each one feels pain or has cognitive function.
Motivational systems have evolved. They enable individuals to ascribe priorities to certain actions, as well as to determine the timing of actions. This facilitates adaptation. A need is a requirement, which is part of the basic biology of an animal, to obtain a particular resource or respond to a particular environmental or bodily stimulus. The need itself is in the brain. It allows effective functioning of the animal. It may be fulfilled by physiology or behaviour but the need is not physiological or behavioural.
The idea of providing for “the five freedoms”, first suggested by W.H.Thorpe in the Brambell Report in 1965, is now replaced by the more scientific concept of needs. The original list just provides a general guideline for non-specialists. Animals have many needs and these can be investigated.
Needs for resources, such as food, water or heat. Needs to carry out actions whose function is to attain an objective. For example: a pig rooting in soil or manipulating material such as straw or twigs, a hen dust-bathing to keep feathers in good condition, a hen or a sow building a nest when about to give birth or lay an egg.
Health refers to what is happening in body systems, including those in the brain, which combat pathogens, tissue damage or physiological disorder. Health is the state ofan individual as regards its attempts to cope with pathology. With disease challenge, as well as with other challenges, difficult or inadequate adaptation results in poor welfare. Health is an important part of welfare. e.g. sole ulcer in cows e.g. osteoarthritis in cats and dogs
For most people, stress implies the effects of a challenge to the individual that disrupts homeostasis resulting in adverse effects. Not just a stimulus which activates energy releasing control mechanisms. Stimuli whose effects are beneficial would not be called stressors by most people. Situations which activate the hypothalamic - pituitary - adrenal cortical axis, but whose effects are useful to the individual, would not be called stressors by most people. Stress is an environmental effect on an individual which overtaxes control systems and results in adverse consequences, eventually reduced fitness. There is no good stress. Taxing stimuli can be good experience.
Recent and expected changes The concepts of animal welfare science have been clarified and the methodology refined. A second recent change is the plethora of work on cognitive ability in animals, including those used on farms, in research or as companions. 3. Welfare aspects of disease. 4. The changing attitudes of people, including consumers 5. Traceability of animal feed and animals. 6. Starvation in animals and effects of extreme temperature. 7. There has been a recent resurgence of interest in quality of life (welfare) in companion animals. 8. Human-animal interactions and the effects of appropriate human contact on animal welfare and production.
In animal welfare science, what are areas for development and new links? Concepts, coping systems, brain mechanisms and feelings. In the assessment of animal welfare: previous focus on pain, stress physiology, behaviour, disease. (Already physiology/ethology/veterinary pathology links, we need more liaison with brain researchers/ psychiatrists.) New work on brain changes during coping with adversity or happiness. What can we learn from zooarchaeology, anatomy? What can we learn from studies of physical ecology and pollution effects? How can we tell when welfare is good? (new behaviour and brain measures) How do we find out what is important to animals? (motivation/psychology)
When poor welfare is evaluated, the relationship between severity and duration should be taken into account Where there is an adverse impact, the area under the severity/time curve is the magnitude of poor welfare. Some measures give information about welfare in the past, e.g. bruises, effects during growth.
Measures ofwelfareThe following are types of measures. • Physiological indicators of pleasure • Behavioural indicators of pleasure • Extent to which strongly preferred behaviours can be shown • Variety of normal behaviours shown or suppressed • Extent to which normal physiological processes and anatomical • development are possible. • Extent of behavioural aversion shown • Physiological attempts to cope • Immunosuppression • Disease prevalence • Behavioural attempts to cope • Behaviour pathology • Brain changes • Body damage prevalence • Reduced ability to grow or breed Effect of loading only or loading • Reduced life expectancy and transport on plasma cortisol in pigs.
BRAIN CHANGES IN RELATION TO WELFARE Which parts of the brain are associated with systems for coping with difficulties? There are cortisol receptors in many parts of the brain e.g. frontal lobes, amygdala and hippocampus. The amygdala is also associated with fear responses (Panksepp 1998). It projects to the paraventricular nucleus of the hypothalamus (PVN). CRH can affect cortex, hippocampus, stria terminalis, amygdala, PVN. Which parts of the brain are associated with good feelings – pleasure? Oxytocin, concentration higher during some pleasurable events, is synthesised in the paraventricular nucleus (PVN) and in the supra-opticnucleus.
TECHNIQUES FROM ARCHAEOLOGY Archaeologists want to know about the life of individuals in the past. The information that they have often comes from bones. Teeth can give indications of problems during life so human and zooarchaeologists use this information. Formation and growth of enamel, dentine, cementum, roots, pulp and bone can be affected by: inflammation, trauma, infection, some endocrine activity during growth (Wiggs and Lobprise 1997).
Poor welfare during development: what effects on teeth might we see? • Growth Slow • Linear Enamel Hypoplasia (LEH) • Tooth Wear • Malposition • Calculus, other pathogen effects • Dental Defects LEH and other measures used by archaeologists to indicate extent of malnutrition, disease and other severe problems.
FLUCTUATING ASYMMETRY Evaluates developmental stability – ability of developmental processes to resist alterations during growth. • Described in a wide range of papers as being affected by: • Inbreeding • Mutations • Nutritional stress • Pollution • Parasites
Studies of FA in chickens kept for meat production • Fast-developing breeds had more FA than Jungle Fowl, perhaps because of • directional selection. • Higher stocking density: 28 birds per m2 resulted in more FA than 20. • Extreme light regime: chickens kept in continuous light: more FA in toes • than in chickens kept in 16 h light, 8h dark regime (Campo et al 2007). Pigs and air quality High ammonia and carbon dioxide led to more FA.
HOW DO WE FIND OUT FROM ANIMALS WHAT THEY NEED? Need:A requirement, which is fundamental in the biology of an animal, to obtain a particular resource or respond to a particular environmental or bodily stimulus. What is preferred? How hard will the individual (choice of floors) work for a resource? (lift weighted door)
Terminology used in motivational strength estimation Resource– commodity or opportunity to perform activity. Demand (as measured) – amount shown of action which enables resource to be obtained. Price – amount of that action required for unit of resource. Income – amount of time or other variable limiting that action Price elasticity of demand– proportional rate at which consumption or demand changes with price. Consumer surplus– a measure of the largest amount which a subject is prepared to spend on a given quantity of the resource. It corresponds to an area beneath an inverse demand curve.
Demand curve Price elasticity of demand : slope at z The area under this inverse demand curve is the consumer surplus of the quantity z.
Mink were trained to perform operants to reach: an extra nest, various objects, a raised platform, a tunnel, an empty cage and a water pool to swim in. The swimming water was given very high priority by the mink.Mason et al (2001) Nature, 410, 35-36.
Scientists should: be objective in their work, separating the science from the ethics; use good methodology for welfare assessment; attempt to develop new methodologies; publish their work whatever the result; and some scientists should ensure that new results become known in the relevant industries and government departments.
Why are animal welfare scientists studying cognition and awareness? Has this subject anything to do with veterinary or animal production teaching and research? Attitudes to animals are affected by evaluations of the animals’ abilities. If they are considered to be stupid and unaware, they are more likely to be treated as objects than as individuals. How should we consider mammals and birds, e.g. domestic animals such as sheep, cattle, horses, dogs, cats, chickens, parrots? How should we consider other vertebrates and the various invertebrates?
Discrimination/Recognition /Cognition of sheep facing forwards, of individual sheep Kendrick
Discrimination……Recognition……link to Emotion(Kendrick) Train sheep to discriminate between 25 pairs of photographs. Cells in medial temporal and prefrontal lobes of cortex fire for particular face. Sheep sometimes vocalise during response. Discriminate human face and some of these cells fire for a particular human face. Most sheep still discriminated when tested 1 or 2 years later. Social recognition, ewe recognising lamb. Starts 2h, consolidates over 12h. At 4-5h: production of brain derived neurotrophic factor - BDNF and its receptor - trk-B. mRNA expression in : olfactory and visual processing systems, temporal cortex and four other cortical regions, hippocampus, amygdala. (Broad et al 2002).
Awareness of an object in the absence of that object Mike Mendl Pigs allowed to find hidden food. One day later they remembered where the food was. César Ades University of São Paulo: When the dog had a keyboard with 8 symbols for: water, food, stroke, go out, toy, urinate, she could indicate what she wanted. Concept of object in absence of object. Concept of symbol linked to that of object. Action of pressing appropriate key linked to concept of object. Ability of pigs to appreciate what is represented in a mirror. (Broom, Sena and Moynihan).
Awareness of own learning / achievement: emotional responses Hagen (CAWA) studied young cattle whilst they were learning.They could put the nose in a hole to cause a gate to open and give access to food 15m away. Yoked controls received access to food after the same interval. In the trials in which their learning curve was steepest, the animals which learned the association had a higher heart-rate in 15s before gate opened than their yoked controls. Also galloping, bucking or kicking when moving to food.
Traceability: animal feed and animals If foods fed to animals can be traced, it is less likely that pathogens emanating from food will be in animal feed. For example, milk or other dairy by-products, even if pasteurised, can carry foot-and-mouth disease or MAP (Mycobacterium avium pseudotuberculosis) and can infect cattle and some other animals. Foot-and-mouth disease causes painful lesions and serious malaise so the welfare of clinically infected animals is very poor. BSE is known to be transmitted in animal feed. If a case is detected, it is necessary to trace all of the food fed to that animal. BSE is very distressing for clinically infected cattle and the consequences of its occurrence can lead to other poor welfare, for example because of cattle movement restrictions.
What is your reaction to the proposal to have traceable animals? If it is: how could I avoid having to have traceable animals? you are thinking in the wrong way! It is in the interest of the meat production industries to maximise traceability because: disease will be controlled better, the welfare of the animals will be better, the public will have more confidence in the product.
Starvation and effects of extreme temperature. Starvationoccurs when there is a shortage of nutrients or energy such that the animal starts to metabolise functional tissues rather than food reserves. (Broom and Fraser 2007). Work by Clive Phillips and colleagues (Agenäs et al 2006) have provided some useful measures for cattle. More measurements of starvation are needed. Also, methods of management that do not have a serious risk of starvation should be developed. The effects of extreme temperature and their effects on welfare also require study and changes in management practice.
When is euthanasia right for my dog or cat? i.e., when should it be killed for its own benefit? When should disease be treated? ‘Quality of life’ is essentially the same in meaning as ‘welfare’. However, whilst welfare can be considered over the short-term or the long-term, quality of life usually refers to a characteristic of an individual over a time-scale longer than a few days.
One of the major developments in animal welfare science in recent years Has been the work of Hemsworth, Barnett and Coleman on the effects of different types of handling on animal welfare and ease of management. If pigs, poultry or cattle are handled gently at the appropriate time, they are easier to handle later, their welfare is better when humans are close, they are easier to manage so the stockperson’s job is better and growth may be better.
Calves reared in individual pens more stressed by transport. Trunkfield et al 1991
Research on experience of human interactions Effects of handling Aubrac calves - Boivin and Le Neindre Measure No handling Weaning Weaning + 6mo Eat concentrate from hand0 100 33 % Allow human touch 0 78 22 % Time to sort animals 20.3 14.7 14.5 s Animals kept still by man 0 100 89 % Animals aggressive 57 0 0 %
Conclusions 1. The moral background has been studied and the role of welfare as an aspect of sustainability considered. 2. The concepts of animal welfare science have been clarified and the methodology refined. 3. There has been much work on cognitive ability in animals. 4. Welfare aspects of disease require more study. 5. The changing attitudes of people, including consumers, should be studied. 6. Traceability of animal feed and animals is necessary. 7. Starvation and effects of extreme temperature as welfare issues. 8. Quality of life means welfare except that it is not used short periods. 9. Study the effects of appropriate human contact on animal welfare.