«Item type Thesis or dissertation Authors Davis, Nicolas Citation Davis, N., Schaffner, C. M., & Smith, T. E. (2005). Evidence that zoo visitors ...»
Although it is generally accepted that welfare refers to a satisfactory or positive state, despite much discussion there is no universal, specific definition of it within scientific literature (Wiepkema & Koolhaas, 1993). Instead there are a variety of different interpretations from different researchers (Appleby, 1999). For example, Broom (1999) suggested a clearly defined concept of welfare is needed for use in precise scientific measurements, legislation and public discussion. It would then allow animal welfare to be compared across different situations or evaluated in a specific situation and assessed objectively. Attempts to define welfare as a purely scientific concept, however, have been questioned. D. Fraser (1995) argued that many of the proposed definitions have serious limitations. They specify very little about what processes contribute to overall welfare or how welfare may be measured.
Instead D. Fraser (1995) sees welfare as a concept that involves subjective values on what is best for the quality of life of animals. Whilst scientific study can measure the various elements that are relevant to welfare, there is no objective method to combine them into a measure of the ‘overall’ welfare of the animal and can do little more than establish a general area of discussion (Duncan & Fraser, 1997; D. Fraser, 1995).
Animal welfare also has been defined as the state of an animal with regards to its attempt to cope with its environment (Broom, 1986), where coping refers to an animal’s responses to help control its interactions with its environment and maintain mental and bodily stability; failure to cope means a reduction in fitness (Broom, 1991). This definition has since been clarified with welfare as a characteristic of an individual at a particular moment in time or over a longer period of time, and the term environment takes account of both internal and external stimuli (Broom, 2007).
This definition recognises that welfare can be very good or very bad, and can vary on a continuum between the two extremes. It also implies good welfare is more than just the absence of disease or discomfort and emotional distress. It involves satisfying the animals’ basic needs as identified by the Five Freedoms (FAWC, 1992).
One of the most widely used concepts of animal welfare encompasses the ‘Five Freedoms of Animal Welfare’ (see Table 1.1). This approach was first adopted by the Farm Animal Welfare Council (FAWC), which was a body set up in response to the Brambell Committee (1965) to look at improving agricultural standards and practices in the UK. Much of the animal welfare legislation in the United Kingdom (e.g. Animal Welfare Act 2006, p. 7) is based upon these five freedoms.
Table 1.1 Farm animal welfare council’s Five Freedoms of Animal Welfare FAWC (1992).
The definition of animal welfare as adopted by the International Primatological Society (IPS) in their captive care guidelines goes beyond that captured by the Five Freedoms. It incorporates aspects of psychological wellbeing, the importance of social contact and acknowledges that for primates, the need to consider cognitive capabilities is also important. This latter definition is developed from the version used by the Association for Zoo and Aquariums (AZA) Animal Welfare Committee (McCann, et al., 2007).
Animal welfare is the degree to which an animal can cope with challenges in its environment as determined by a combination of measures of health (including pre-clinical physiological responses) and measures of psychological wellbeing.
Good health represents the absence of diseases or physical/physiological conditions that result (directly or indirectly) from inadequate nutrition, exercise, social groupings, or other environmental conditions to which an animal fails to cope successfully.
Psychological wellbeing is dependent on there being the opportunity for animals to perform strongly motivated, species-appropriate behaviours, especially those that arise in response to aversive stimuli. Enhanced psychological wellbeing is conditional on the choices animals have to respond appropriately to variable environmental conditions, physiological states, developmental stages and social situations, and the extent to which they can develop and use their cognitive abilities through these responses. (p. 49)
1.3 Measurement of animal welfare
In order to meet the wide ranging definitions of welfare as captured by the Five Freedoms and the IPS guidelines, is it essential to be able to operationalise and measure welfare, although this also poses challenges. The measurement and assessment of welfare is a multidimensional discipline with a number of behavioural, physiological and biochemical techniques in use (Botreau, Veissier, Butterworth, Bracke, & Keeling, 2007; Broom, 2007; Dawkins, 2004; D. Fraser, 1995; Lane, 2006; G. Mason & Mendl, 1993). In addition, assessment can occur at different levels including the individual, the group or an entire husbandry system.
The method adopted by scientists, however, will depend on their adopted definition of animal welfare and their conceptualisation of it. Poor welfare has been indicated by a suppressed immune function (Honess, Marin, Brown, & Wolfensohn, 2005), gastric ulceration and anorexia (Bassett & Buchanan-Smith, 2007), reduced reproductive output (A. F. Fraser & Broom, 1990), aberrant behaviour (Dawkins, 2004; Wechsler, 2007), altered heart rate (Aureli, Preston, & de Waal, 1999; Clarke, Mason, & Mendoza, 1994; Honess & Marin, 2006), display of abnormal behaviours such as apathy and stereotypy (G. Mason & Latham, 2004) and increased activity in the pituitary-adrenocortical system (G. Mason & Mendl, 1993; Morgan & Tromborg, 2007; Wiepkema & Koolhaas, 1993). Other new areas of research include assessing emotions and cognition (Boissy, Arnould, et al., 2007) including cognitive bias (Matheson, Asher, & Bateson, 2008) and brain measures (Broom & Zanella, 2004) as an indication of welfare.
Three approaches have been used systematically to investigate animal welfare (Appleby, 1999; Duncan & Fraser, 1997; Webster, 2005b). Each approach has a separate definition for animal welfare and consequently unique research strategies.
The first approach is concerned with the animal’s subjective feelings (Wemelsfelder, 2007). The second approach focuses on the extent to which animals display natural behaviours (Wechsler, 2007) and the third approach examines the degree to which an animal exhibits ‘normal’ biological functioning (Hughes & Curtis, 1997).
1.3.1 Subjective feelings The first approach recognises animals as sentient beings and emphasises the subjective feelings of animals and the use of science to understand them (Wemelsfelder, 2007). It implies that animals have emotional capacities and will attempt to minimise negative emotions such as fear and frustration, while seeking positive emotions such as joy and pleasure (Boissy, Arnould, et al., 2007; Dawkins, 2006). The idea of an evolutionary continuity of animals experiencing emotions, such as fear or anger, is not new and was first proposed by Darwin (1871, 1872).
However, whether animals experience even the basic range of states of consciousness, such as emotions, considering previous experiences or feeling pain, is difficult to assess and has been referred to as the ‘hard problem’ (Chalmers, 1995).
Although once seen as unscientific the idea of subjective feelings and emotions for animals is now generally accepted (Boissy, Arnould, et al., 2007), although there are still exceptions (Kennedy, 1992). The supporters of this approach argue that animal welfare is only affected if the animal is experiencing an unpleasant mental state, such as anxiety, boredom or frustration (Dawkins, 1990; Duncan, 1993;
Brian O. Hughes, 1989; Sandøe & Simonsen, 1992). Therefore, even if an animal has health issues, or if its physical needs are not met, if the animal cannot feel these then there is no impact on its welfare.
Developing an understanding of unobservable processes involves additional logical steps and assumptions that are open to interpretation (Duncan & Fraser, 1997). It has been proposed that evidence of animal cognition and emotion could be assessed through behaviour, by ‘asking’ the animals what they want through the use of preference tests, parallels with our own emotions and even brain imaging to investigate whether animals are sentient (Dawkins, 2006). The assumption is that the animals will make a valid preference that will either provide an increased positive or reduced negative state. However, there are limitations to this approach (D. Fraser & Matthews, 1997). An individual’s choice could be affected by various factors such as individual differences, age, and experience, time of day or reproductive state, which potentially confounds such research. The link between preference and welfare is also limited to choices that are within an animal’s capacity to make a valid choice;
therefore it must fall within an animal’s sensory or cognitive abilities. The concept of emotions however only refers to the immediate state of welfare of the animal at that time, and does not account for longer term issues or their general fitness (Webster, 2005b).
The use of cognitive science has also been highlighted as a means of researching emotions in animals as a means of improving their quality of life (Boissy, Arnould, et al., 2007). Another approach may be to use qualitative judgements of an animal’s behaviour to assess their emotive state (Wemelsfelder, 2007). Providing it is based on knowledge of species-specific behaviours, and that an experienced person is making the assessment and animals are viewed as sentient beings, an approach that relies on subjective feelings can function in a scientific context.
Another method relies on the ‘argument by analogy’ by measuring responses to known unpleasant experiences in humans and looking for similar responses in animals. This relies on the presumption that mental suffering in animals is accompanied by similar physiological and behavioural responses to suffering in humans (Dawkins, 1990; Sandøe & Simonsen, 1992). The effect of emotional states on physiology offers opportunities for interpretation of subjective feelings in animals (Boissy, Manteuffel, et al., 2007; Gonyou, 1993). For example, the effect of emotions on humans influences the hypothalamic pituitary adrenal (HPA) axis and cortisol levels (Hodges, Jones, & Stockham, 1962). Studies in human participants have also shown a relationship between higher cortisol responses and greater expressions to negative emotions (Lewis & Ramsay, 2002, 2005). In animals further research is required to establish how such physiological changes in different species of animals can relate to various emotions (Désiré, Boissy, & Veissier, 2002).
1.3.2 Natural behaviours The second approach to measuring welfare looks at providing natural environments that allow animals to perform most types of species-specific behaviour (Kiley-Worthington, 1989; Rollin, 1993; Shepherdson, 1999; Wechsler, 2007). The degree to which animals perform their natural behaviours is used as an indication of welfare state. The assumption being that the more ‘natural’ the behavioural repertoire displayed, then the better the animals’ state of welfare. This idea is included in various animal welfare legislation and codes in the UK, which states that animals have a need to express most of their normal patterns of behaviour (FAWC, 1992;
Thorpe, 1967). However, as animals have such behavioural diversity the consequences of not performing such behaviours will also be varied, particularly if the endpoint of a behavioural need is already provided in their environment (Baxter, 1983; Dawkins, 1983). For example, is there a behavioural need for anti predatory behaviour in captivity even when there are no predators present? Suffering should only result if an animal is highly motivated to perform a particular behaviour, but due to its environment becomes frustrated if it is unable to carry it out (B.O. Hughes & Duncan, 1988; Young, 1999).
Information regarding the species-typical behaviour patterns of wild animals (Stolba & Wood-Gush, 1989) can be used to establish normal behaviour patterns, and these ethograms could then be used to identify the specific behaviours that are important for the animals to perform (Veasey, Waran, & Young, 1996a). Motivation to perform these behaviours, such as foraging for food, could lead to suffering if they are not allowed, and the freedom to express normal behaviour is included in the UK animal welfare codes (MAFF, 1983). However, animals in the wild are regularly exposed to adverse conditions, not present in captivity and that are detrimental to their welfare, such as cold, hunger or the presence of predators (Veasey, Waran, & Young, 1996b). Therefore, a full repertoire of behaviour, which includes those evolved to cope with adverse conditions, could require the animals to be exposed to conditions that reduce welfare, which in turn have a negative impact on health (Dawkins, 2004).
An appreciation of the need for animals to express a greater range of speciesspecific behavioural repertoires has occurred more recently in the farming and zoo communities. For example, there has been a recent growth of interest in high welfare standard certification schemes in farming through both legislation and as a result of consumer demand (Botreau, Veissier, Butterworth, Bracke, & Keeling, 2007; Broom, 2007). Modern zoological parks have also recognised the benefits of housing animals in a manner that encourages greater naturalistic behaviour by recreating more natural environments (Maple & Finlay, 1989). However, it is the outcome of the environment and its effect on promoting natural behaviour that is relevant to an animal’s welfare rather than the natural habitat itself (Duncan & Fraser, 1997). In addition, this approach proves difficult to interpret into effective recommendations or detailed legislation (Appleby, 1999).
Contexts in the animals’ captive environment that create internal uncertainty, such as absence of food or the presence of a rival can impact on an animal’s welfare.