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Breeding for pleasure: the value of pleasure and pain in evolution and animal welfare

Published online by Cambridge University Press:  01 January 2023

J Yeates
J Yeates*
Affiliation:
School of Veterinary Science, University of Bristol, Langford House, Langford BS40 5DU, UK; email: [email protected]
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Abstract

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Farming and laboratory industries face questions about whether to breed animals with altered capacities for pleasure and pain. This paper addresses this issue from different approaches to animal welfare based on experiences, fitness and naturalness. This can illuminate both the breeding-related issues and the different approaches themselves. These differences have practical implications for decisions about animal breeding. All three approaches will agree that pleasure that is adaptive in natural environments has positive value and that maladaptive pain has negative value. However, where animals’ environments will not be natural, experiences-based approaches may support breeding animals that experience more pleasure and less pain or insentient animals; whereas, in some cases, fitness-based and naturalness-based approaches might favour the breeding of animals that experience more pain and less pleasure.

Keywords

animal welfarebreedingextrinsic valuefitnesspleasuresignatory value
Type
Research Article
Information
Animal Welfare , Volume 19 , Issue S1: Proceedings of the UFAW International Symposium ‘Darwinian selection, selective breeding and the welfare of animals’ Bristol, 2009 , May 2010 , pp. 29 - 38
Copyright
© 2010 Universities Federation for Animal Welfare

References

Allen, C and Beckoff, M 2007 Animal minds, cognitive ethology and ethics. The Journal of Ethics 11: 299–317CrossRefGoogle Scholar
Appleby, MC and Sand⊘e, P 2002 Philosophical debate on the nature of well-being: implications for animal welfare. Animal Welfare 11(3): 283–294Google Scholar
Baars, BJ 2002 The conscious access hypothesis: origins and recent evidence. Trends in Cognitive Sciences 6: 47–52CrossRefGoogle ScholarPubMed
Belknap, JK, Haltli, NR, Goebel, DM and Lamé, M 1983 Selective breeding for high and low levels of opiate-induced analgesia in mice. Behavior Genetics 13: 383–396CrossRefGoogle ScholarPubMed
Berridge, KC 1996 Food reward: brain substrates of wanting and liking. Neuroscience and Biobehavioural Reviews 20(1): 1–25CrossRefGoogle ScholarPubMed
Berridge, KC 2003 Pleasures of the brain. Brain and Cognition 52: 106–128CrossRefGoogle ScholarPubMed
Berridge, KC and Robinson, TE 2003 Parsing reward. Trends in Neuroscience 26: 507–513CrossRefGoogle ScholarPubMed
Berridge, KC and Winkielman, P 2003 What is an unconscious emotion? (The case for unconscious ‘liking’). Cognition Emotion 17: 181–211CrossRefGoogle Scholar
Blackshaw, JK, Swain, AJ, Blackshaw, AW, Thomas, FJM and Gillies, KJ 1997 The development of playful behaviour in piglets from birth to weaning in three farrowing environments. Applied Animal Behaviour Science 55: 37–49CrossRefGoogle Scholar
Boden, MA 1990 Escaping from the Chinese room. In: Boden, MA (eds) The Philosophy of Artificial Intelligence pp 89–104. Oxford University Press: Oxford, UKGoogle Scholar
Boissy, A, Manteuffel, G, Jensen, MB, Moe, RO, Spruijt, B, Keeling, LJ, Winckler, C, Forkman, B, Dimitrovi, I, Langbein, J, Bakken, M, Veissier, I and Aubert, A 2007 Assessment of positive emotions in animals to improve their welfare. Physiology and Behavior 92: 375–397CrossRefGoogle ScholarPubMed
Bracke, MBM and Hopster, H 2006 Assessing the importance of natural behaviour for animal welfare. Journal of Agricultural and Environmental Ethics 19: 77–89CrossRefGoogle Scholar
Bradley, B 1998 Extrinsic value. Philosophical Studies 91: 109–126CrossRefGoogle Scholar
Breslin, PA, Spector, AC and Grill, HJ 1992 A quantitative comparison of taste reactivity behaviours to sucrose before and after lithium chloride pairings: A unidimensional account of palatability. Behavioural Neuroscience 106: 820–836CrossRefGoogle ScholarPubMed
Broom, DM 1988 The scientific assessment of animal welfare. Applied Animal Behaviour Science 20: 5–19CrossRefGoogle Scholar
Broom, DM 1998 Welfare, stress and the evolution of feelings. Advances in the Study of Behaviour 27: 371–403CrossRefGoogle Scholar
Broom, DM 2007 Quality of life means welfare: How is it related to other concepts and assessed? Animal Welfare 16: S45–S53Google Scholar
Broom, DM and Johnson, K 1993 Stress and Animal Welfare. Kluwer Academic Publishers: Dordrecht, The NetherlandsCrossRefGoogle Scholar
Burgdorf, J and Panksepp, J 2006 The neurobiology of positive emotions. Neuroscience and Biobehavioural Reviews 30: 173–187CrossRefGoogle ScholarPubMed
Burman, OHP, Parker, R, Paul, ES and Mendl, M 2008 A spatial judgement task to determine background emotional state in laboratory rats, Rattus norvegicus. Animal Behaviour 76: 801–809CrossRefGoogle Scholar
Cabanac, M 1971 Physiological role of pleasure. Science 173: 1103–1107CrossRefGoogle Scholar
Cabanac, M 1979 Sensory pleasure. Quarterly Review of Biology 54: 1–29CrossRefGoogle ScholarPubMed
Cabanac, M 1992 Pleasure: the common currency. Journal of Theoretical Biology 155: 173–200CrossRefGoogle ScholarPubMed
CAWC 2008 Fixing ancestral problems: genetics and welfare in companion animals focusing on syringomyelia in Cavalier King Charles Spaniels as an example. Report of the Companion Animal Welfare Council Workshop. 29th April 2008. House of Lords, London, UKGoogle Scholar
Chalmers, D 1996 The Conscious Mind. Oxford University Press: Oxford, UKGoogle Scholar
Damasio, AR 1994 Descartes’ Error: Emotion, Reason and the Human Brain. Picador: London, UKGoogle Scholar
Danbury, TC, Weeks, CA, Waterman-Pearson, AE, Kestin, SC and Chambers, JP 2000 Self-selection of the analgesic drug carprofen by lame broiler chickens. Veterinary Record 146(11): 307–311CrossRefGoogle ScholarPubMed
Dantzer, R 1991 Stress, stereotypies and welfare. Behavioural Processes 25: 95–102CrossRefGoogle ScholarPubMed
Darwin, C 1872 The Expressions of the Emotions in Man and Animals. Longmans: London, UKCrossRefGoogle Scholar
Dawkins, MS 1988 Behavioural deprivation: a central problem in animal welfare. Applied Animal Behaviour Science 20: 209–225CrossRefGoogle Scholar
Dawkins, MS 1990 From an animal's point of view: motivation, fitness and animal welfare. Behavioral and Brain Sciences 13: 1–60CrossRefGoogle Scholar
Dawkins, MS 1998 Evolution and animal welfare. Quarterly Review of Biology 73: 305–328CrossRefGoogle ScholarPubMed
Dawkins, MS 2000 Animal minds and animal emotions. American Zoologist 40: 883–888Google Scholar
Dawkins, MS 2001 Who needs consciousness? Animal Welfare 10: S19–S32Google Scholar
Dawkins, MS 2003 Behaviour as a tool in the assessment of animal welfare. Zoology 106(4): 383–387CrossRefGoogle ScholarPubMed
Dawkins, MS 2005 The science of suffering. In: McMillan, FD (ed) Mental Health and Wellbeing in Animals pp 47–56. Blackwell: Ames, USAGoogle Scholar
D’Eath, RB, Lawrence, AB, Conington, J, Olsson, IAS and Sand⊘e, P 2010 Breeding for behavioural change in farm animals: practical and ethics considerations. Animal Welfare 19: S17–S27Google Scholar
Dearborn, GVN 1932 A case of congenital pure analgesia. Journal of Nervous and Mental Disease 75: 612–615CrossRefGoogle Scholar
DeGrazia, D 1998 Wellbeing of animals. In: Beckoff, M and Meany, CA (eds) Encyclopedia of Animal Rights and Animal Welfare pp 359–360. Greenwood Press: Westport, USAGoogle Scholar
Désiré, L, Boissy, A and Veissier, I 2002 Emotion in farm animals: a new approach to animal welfare in applied ethology. Behavioural Processes 60: 165–180CrossRefGoogle ScholarPubMed
Duncan, I 1993 Welfare is to do with what animals feel. Journal of Agricultural & Environmental Ethics 6(2): S8-S14Google Scholar
FAWC (Farm Animal Welfare Council) 1998a Report on the Welfare of Broiler Breeders. FAWC: London, UKGoogle Scholar
FAWC (Farm Animal Welfare Council) 1998b Report on the Implications of Cloning for the Welfare of Farmed Livestock. FAWC: London, UKGoogle Scholar
Feldman, F 1986 Doing the Best We Can: An Essay in Informal Deontic Logic. D. Reidel: Dordrecht, The NetherlandsCrossRefGoogle Scholar
Feldman Barrett, L and Russell, JA 1998 Independence and bipolarity in the structure of current affect. Journal of Personality and Social Psychology 74: 967–984CrossRefGoogle Scholar
Fillingim, RB, Wallace, MR, Herbstman, DM, Ribeiro-Dasilva, M and Staud, R 2009 Genetic contributions to pain: a review of findings in humans. Oral Diseases 14: 673–682CrossRefGoogle Scholar
Frankena, WK 1963 Ethics. Prentice Hall: Englewood Cliffs, USAGoogle Scholar
Fraser, D 1995 Science, values and animal welfare: exploring the ‘inextricable connection’. Animal Welfare 4: 103–117Google Scholar
Fraser, D 1998 Animal Welfare. In: Beckoff, M and Meany, CA (eds) Encyclopedia of Animal Rights and Animal Welfare pp 55–57. Greenwood Press: Westport, USAGoogle Scholar
Fraser, D and Duncan, IJ 1998 ‘Pleasures’, ‘pains’ and animal welfare: toward a natural history of affect. Animal Welfare 7: 383–396Google Scholar
Fraser, D, Weary, DM, Pajor, EA and Milligan, BN 1997 A scientific concept of animal welfare that reflects ethical concerns. Animal Welfare 6: 187–205Google Scholar
Gregory, NG 2004 Physiology and Behaviour of Animal Suffering. UFAW/Blackwell: Oxford, UKCrossRefGoogle Scholar
Grill, HJ and Norgren, R 1978 The taste reactivity test I. Mimetic responses to gustatory stimuli in neurologically normal rats. Brain Research 143: 263–279CrossRefGoogle ScholarPubMed
Gross, JJ, John, OP and Richards, JM 2000 The dissociation of emotion expression from emotion experience: A personality perspective. Personality and Social Psychology Bulletin 26: 712–726CrossRefGoogle Scholar
Harding, E, Paul, ES and Mendl, M 2004 Cognitive bias and affective state. Nature 427: 312CrossRefGoogle ScholarPubMed
Harrison, P 1989 Theodicy and animal pain. Philosophy 64: 79–92CrossRefGoogle Scholar
Hassenbusch, SJ, Pillay, PK and Barnett, GH 1990 Radiofrequency cingulotomy for intractable cancer pain using stereotaxis guided by magnetic resonance imaging. Neurosurgery 27: 220–223CrossRefGoogle ScholarPubMed
Hauser, L 1993 Reaping the whirlwind: reply to Harnad's other bodies, other minds. Minds and Machines 3: 219–238CrossRefGoogle Scholar
Heath, RG 1972 Pleasure and brain activity in man. Journal of Nervous and Mental Disease 154: 3–18CrossRefGoogle ScholarPubMed
Heeger, R and Brom, FWA 2001 Intrinsic value and direct duties: from animal ethics towards environmental ethics. Journal of Agricultural and Environmental Ethics 14: 241–252CrossRefGoogle Scholar
Hinde, RA 1985 Was ‘the expression of the emotions’ a misleading phrase? Animal Behaviour 33: 985–992CrossRefGoogle Scholar
Hornemann, T, Penno, A, Richard, S, Nicholson, G, van Dijk, FS, Rotthier, A, Timmerman, V and von Eckardstein, A 2009 A systematic comparison of all mutations in hereditary sensory neuropathy type I (HSAN I) reveals that the G387A mutation is not disease associated. Neurogenetics 10: 135–143CrossRefGoogle Scholar
Hyslop, A and Jackson, FC 1972 The analogical inference to other minds. American Philosophical Quarterly 9(2): 168–176Google Scholar
Indo, Y, Tsurata, Y, Karim, MA, Ohta, K, Kawano, T, Mitsubuchi, H, Tonoki, H, Awaya, Y and Matsuda, I 1996 Mutations in the TRKA/NGF receptor gene in patients with congenital insensitivity to pain with anhidrosis. Nature Genetics 13: 485–488CrossRefGoogle ScholarPubMed
Jestico, JV, Urry, PA and Efphimiou, J 1985 An hereditary sensory and autonomic neuropathy transmitted as an X-linked recessive trait. Journal of Neurology, Neurosurgery, and Psychiatry 48: 1259–1264CrossRefGoogle ScholarPubMed
Jones, RB and Hocking, PM 1999 Genetic selection for poultry behaviour: big bad wolf or friend in need? Animal Welfare 8(4): 343–359Google Scholar
Kanis, E, De Greef, KH, Hiemstra, A and van Arendonk, JAM 2005 Breeding for societally important traits in pigs. Journal of Animal Science 83: 948–957CrossRefGoogle ScholarPubMed
Kelley, AE, Baldo, BA, Pratt, WE and Will, MJ 2005 Corticostriatal-hypothalamic circuitry and food motivation: Integration of energy, action and reward. Physiology and Behaviour 86: 773–795CrossRefGoogle ScholarPubMed
Knutson, B, Burgdorf, J and Panksepp, J 2002 Ultrasonic vocalisations as indices of affective states in rats. Psychological Bulletin 128: 961–977CrossRefGoogle Scholar
Korsgaard, C 1983 Two distinctions in goodness. Philosophical Review 92: 169–195CrossRefGoogle Scholar
LaCroix-Fralish, ML and Mogil, JS 2009 Progress in genetic studies of pain and analgesia. Annual Review of Pharmacology and Toxicology 49: 97–121CrossRefGoogle ScholarPubMed
Lane, RD, Ahern, GL, Schwarz, GE and Kasniak, AW 1997 Is alexithymia the emotional equivalent of blindsight? Biological Psychiatry 42: 834–844CrossRefGoogle ScholarPubMed
Lawrence, AB, Conington, J and Simm, G 2004 Breeding and animal welfare: practical and theoretical advantages of multi-trait selection. Animal Welfare 13: S191–S196Google Scholar
Lerner, JS and Keltner, D 2000 Beyond valence: Toward a model of emotion-specific influence on judgement and choice. Cognition Emotion 14: 473–493CrossRefGoogle Scholar
Lewis, CI 1955 The Ground and Nature of the Right. Columbia University Press: New York, USACrossRefGoogle Scholar
Lindahl, BIB 1997 Consciousness and biological evolution. Journal of Theoretical Biology 187: 613–626CrossRefGoogle ScholarPubMed
Lund, V, Coleman, G, Gunnarsson, S, Appleby, MC and Karkinen, K 2006 Animal welfare science. Working at the interface between the natural and social sciences. Applied Animal Behaviour Science 97: 37–49CrossRefGoogle Scholar
Lundberg, R 1985 What kind of good is a kind and caring heart? Journal of Value Inquiry 19: 119–131CrossRefGoogle Scholar
Lykken, D and Tellegen, A 1996 Happiness is a stochastic phenomenon. Psychological Science 7: 186–189CrossRefGoogle Scholar
Lyubomirsky, S, King, L and Diener, E 2005 The benefits of frequent positive affect: does happiness lead to success? Psychological Bulletin 131: 803–855CrossRefGoogle Scholar
MacArthur Clark, JA, Potter, M and Harding, E 2006 The welfare implications of animal breeding and breeding technologies in commercial agriculture. Livestock Science 103: 270–281CrossRefGoogle Scholar
Mason, G 1991a Stereotypies: a critical review. Animal Behaviour 41: 1015–1037CrossRefGoogle Scholar
Mason, GJ 1991b Stereotypies and suffering. Behavioural Processes 25: 103–115CrossRefGoogle Scholar
Mason, G and Mendl, M 1993 Why is there no simple way of measuring animal welfare? Animal Welfare 2: 301–319Google Scholar
McGreevy, PD 2007 Breeding for quality of life. Animal Welfare 16: S125–S128Google Scholar
McGreevy, PD and Nicholas, FW 1999 Some practical solutions to welfare problems in dog breeding. Animal Welfare 8: 329–341Google Scholar
McMillan, FD 2003 Maximising quality of life in ill animals. Journal of the American Animal Hospital Association 39: 227–235CrossRefGoogle Scholar
Meadows, ME and Kaplan, RF 1994 Dissociation of autonomic and subjective responses to emotional slides in right hemisphere damaged patients. Neuropsychologia 32: 847–856CrossRefGoogle ScholarPubMed
Mogil, JS 1999 The genetic mediation of individual differences in sensitivity to pain and its inhibition. Proceedings of the National Academy of Sciences 96: 7744–7751CrossRefGoogle ScholarPubMed
Mogil, JS, Wilson, SG, Bon, K, Lee, SE, Chung, K, Raber, P, Pieper, JO, Hain, HS, Belknap, JK, Hubert, L, Elmer, GI, Chung, JM and Devor, M 1999a Heritability of nociception I. Responses of eleven inbred mouse strains on twelve measures of nociception. Pain 80: 67–82CrossRefGoogle Scholar
Mogil, JS, Wilson, SG, Bon, K, Lee, SE, Chung, K, Raber, P, Pieper, JO, Hain, HS, Belknap, JK, Hubert, L, Elmer, GI, Chung, JM and Devor, M 1999b Heritability of nociception II. ‘Types’ of nociception revealed by genetic correlation analysis. Pain 80: 83–93CrossRefGoogle Scholar
Mogil, JS, Yu, L and Basbaum, AI 2000 Pain genes? Natural variation and transgenic mutants. Annual Review of Neuroscience 23: 777–811CrossRefGoogle ScholarPubMed
Moody, T 1994 Conversations with zombies. Journal of Consciousness Studies 1: 196–200Google Scholar
Morgan, CL 1984 An Introduction to Comparative Psychology. Walter Scott: London, UKGoogle Scholar
Nauta, WJ, Baars, T, Saatkamp, H, Weenink, D and Roep, D 2009 Farming strategies in organic dairy farming: effects on breeding goal and choice of breed. An explorative study. Livestock Science 121: 187–199CrossRefGoogle Scholar
Nielsen, CS, Stubhaug, A, Price, DD, Vassend, O, Czajkowski, N and Harris, JR 2008 Individual differences in pain sensitivity: genetic and environmental contributions. Pain 136: 21–29CrossRefGoogle ScholarPubMed
Norbury, TA, MacGregor, AJ, Urwin, J, Spector, TD and McMahon, SB 2007 Heritability of responses to painful stimuli in women: a classical twin study. Brain 130: 3041–3049CrossRefGoogle ScholarPubMed
Nordenfelt, L 2006 Animal and Human Health and Welfare: A Comparative Philosophical Analysis. CABI: Wallingford, UKGoogle Scholar
Nozick, R 1974 Anarchy, State and Utopia. Blackwell: Malden, MA, USAGoogle Scholar
Oertel, B and Lötsch, J 2008 Genetic mutations that prevent pain: implications for future pain medication. Pharmacogenomics 9(2): 179–194CrossRefGoogle ScholarPubMed
Olds, ME and Forbes, JL 1981 The central basis of motivation: intracranial self-stimulation studies. Annual Review of Psychology 32: 523–574CrossRefGoogle ScholarPubMed
Olsson, IAS, Gamborg, C and Sand⊘e, P 2005 Taking ethics into account in farm animal breeding: what can breeding companies achieve? Journal of Agricultural and Environmental Ethics 19: 37–46CrossRefGoogle Scholar
O’Neill, J 1992 The varieties of intrinsic value. Monist 75: 119–137CrossRefGoogle Scholar
Panksepp, J 1994 Evolution constructed the potential for subjective experience within the neurodynamics of the mammalian brain. In: Ekman, P and Davidson, RJ (eds) The Nature of Emotion: Fundamental Questions pp 396–399. Oxford University Press: Oxford, UKGoogle Scholar
Panksepp, J and Burgdorf, J 2000 50-kHz chirping (laughter?) in response to conditioned and unconditioned tickle-induced reward in rats: effects of social housing and genetic variables. Behavioural and Brain Research 115: 25–38CrossRefGoogle ScholarPubMed
Panocka, I, Marek, P and Sadowski, B 1986 Inheritance of stress-induced analgesia in mice. Selective breeding study. Brain Research 397: 152–155CrossRefGoogle ScholarPubMed
Popper, KR 1978 Natural selection and the emergence of mind. Dialectica 32: 339–355CrossRefGoogle Scholar
Pressman, S and Cohen, S 2005 Does positive affect influence health? Psychological Bulletin 131: 925–971CrossRefGoogle ScholarPubMed
Rabinowicz, W and R⊘nnow-Rasmussen, T 1999 A distinction in value: intrinsic and for its own sake. Proceedings of the Aristotelian Society 100: 33–52CrossRefGoogle Scholar
Rauw, WM, Kanis, E, Noordhuizen-Stassen, EN and Grommers, FJ 1998 Undesirable side effects of selection for high production efficiency in farm animals: as review. Livestock Production Science 56: 15–33CrossRefGoogle Scholar
Rollin, BE 1995 The Frankenstein Syndrome: Ethical and Social Issues in the Genetic Engineering of Animals. Cambridge University Press: Cambridge, UKCrossRefGoogle Scholar
Rusbridge, C 2007 Chiari-like malformation and syringomyelia in the Cavalier King Charles spaniel. PhD dissertation, University of Utrecht. Available at http://igitur-archive.library.uu.nl/dissertations/2007-0320-201201/full.pdfGoogle Scholar
Rusbridge, C, Greitz, D and Iskandar, BJ 2006 Syringomyelia: current concepts in pathogenesis, diagnosis, and treatment. Journal of Veterinary Internal Medicine 20(3): 469–479CrossRefGoogle Scholar
Ryle, G 1946/1990 The Concept of Mind. Penguin: London, UKGoogle Scholar
Sand⊘e, P 1999 Quality of life, three competing views. Ethical Theory and Moral Practice 2: 11–23CrossRefGoogle Scholar
Sand⊘e, P, Christiansen, SB and Appleby, MC 2003 Farm animal welfare: the interaction of ethical questions and animal welfare science. Animal Welfare 12: 469–478Google Scholar
Sand⊘e, P, Holtug, N and Simonsen, HB 1996 Ethical limits to domestication. Journal of Agricultural and Environmental Ethics 9: 114–122CrossRefGoogle Scholar
Sand⊘e, P, Nielsen, BL, Christensen, LG and S⊘rensen, P 1999 Staying good while playing God. The ethics of breeding farm animals. Animal Welfare 8: 313–328Google Scholar
Sand⊘e, P and Simonsen, HB 1992 Assessing animal welfare: where does science end and philosophy begin? Animal Welfare 1: 257–267CrossRefGoogle Scholar
Scherer, KR, Dan, ES and Flykt, A 2006 What determines a feeling's position in affective space? A case for appraisal. Cognition and Emotion 20(1): 92–113CrossRefGoogle Scholar
Schlesinger, G 1974 Induction and other minds. Australian Journal of Philosophy 52(1): 3–21CrossRefGoogle Scholar
Schulman, H, Tsodikow, V, Einhorn, M, Lecy, Y, Shorer, Z and Hertzanu, Y 2001 Congenital insensitivity to pain with anhidrosis (CIPA): the spectrum of radiological findings. Pediatric Radiology 31: 701–705CrossRefGoogle ScholarPubMed
Searle, J 1984 Minds, Brains & Science: The 1984 Reith Lectures. Penguin Books: London, UKGoogle Scholar
Seth, AK, Baars, BJ and Edelman, DB 2005 Criteria for consciousness in humans and other mammals. Consciousness and Cognition 14: 119–139CrossRefGoogle ScholarPubMed
Sherwin, C 2001 Can invertebrates suffer? Or, how robust is argument by analogy? Animal Welfare 10: S103–S118Google Scholar
Shir, Y, Zeltser, R, Vatine, JJ, Carmi, G, Belfer, I, Zangen, A, Overstreet, D, Raber, P and Seltzer, Z 2001 Correlation of intact sensibility and neuropathic pain-related behaviors in eight inbred and outbred rat strains and selection lines. Pain 90: 75–82CrossRefGoogle ScholarPubMed
Shizgal, P 1997 Neural basis of utility estimation. Current Opinion in Neurobiology 7(2): 198–208CrossRefGoogle ScholarPubMed
Smeyne, RJ, Klein, R, Schnapp, A, Long, LK, Bryant, S, Lewin, A, Lira, SA and Barbacid, M 1994 Severe sensory neuropathies in mice carrying a disrupted Trk/NGF receptor gene. Nature 368: 246–249CrossRefGoogle Scholar
Smith, JW 1948 Intrinsic and extrinsic good. Ethics 58(3): 195–208CrossRefGoogle Scholar
Spinka, M, Newbury, RC and Bekoff, M 2001 Mammalian play: training for the unexpected. Quarterly Review of Biology 76: 141–168CrossRefGoogle ScholarPubMed
Spruijt, BM, van den Bos, R and Pijlman, FTA 2001 A concept of welfare based on reward evaluating mechanisms in the brain: anticipatory behaviour as an indicator for the state of reward systems. Applied Animal Behaviour Science 72: 145–171CrossRefGoogle ScholarPubMed
Suriu, C, Khayat, M, Weiler, M, Kfir, N, Cohen, C, Zinger, A, Aslanidis, C, Schmitz, G and Falik-Zaccai, TC 2009 Skoura, a genetic island for congenital insensitivity to pain and anhidrosis among Moroccan Jews, as determined by a novel mutation in the NTRK1 gene. Clinical Genetics 75: 230–236CrossRefGoogle ScholarPubMed
Tannenbaum, J 1991 Ethics and animal welfare: the inextricable connection. Journal of the American Veterinary Medical Association 198: 1360–1376Google ScholarPubMed
Thrush, DC 1973 Congenital insensitivity to pain: a clinical, genetic and neurophysiological study of four children from the same family. Brain 96: 369–386CrossRefGoogle ScholarPubMed
UFAW 2009 Genetic Welfare Problems of Companion Animals: Syringomyelia in the Cavalier King Charles Spaniel. Available at http://www.ufaw.org.uk/syring.phpGoogle Scholar
van Ree, JM, Gerrits, MAFM and Vandershuren, LJMJ 1999 Opioids, reward and addiction: an encounter of biology, psychology and medicine. Pharmacological Reviews 51: 341–396Google ScholarPubMed
Verhagen, JV and Engelen, L 2006 The neurocognitive bases of human multimodal food perception. Neuroscience and Biobehavioural Reviews 30: 613–650CrossRefGoogle ScholarPubMed
Webster, J 2005 Animal Welfare: Limping Towards Eden. UFAW/Blackwell: Oxford, UKCrossRefGoogle Scholar
Wechsler, B 1995 Coping and coping strategies: A behavioural view. Applied Animal Behaviour Science 43: 123–134CrossRefGoogle Scholar
Wechsler, B and Lea, SEG 2007 Adaptation by learning: Its significance for farm animal husbandry. Applied Animal Behaviour Science 108: 197–214CrossRefGoogle Scholar
Wemelsfelder, F 1997 The scientific validity of subjective concepts in models of animal welfare. Applied Animal Behaviour Science 53: 75–88CrossRefGoogle Scholar
Wemelsfelder, F 2001 The inside and outside aspects of consciousness: complementary approaches to the study of animal emotion. Animal Welfare 10: S129–S139Google Scholar
Wilkinson, HA, Davidson, KM and Davidson, RI 1999 Bilateral anterior cingulotomy for chronic non-cancer pain. Neurosurgery 45(5): 1129–1136CrossRefGoogle Scholar
Wilson, SG and Mogil, JS 2001 Measuring pain in the (knockout) mouse: big challenges in a small mammal. Behavioural Brain Research 125: 65–73CrossRefGoogle Scholar
Winkielman, P and Berridge, KC 2004 Unconscious emotion. Current Directions in Psychological Science 13: 120–123CrossRefGoogle Scholar
Wittgenstein, L 1953 Philosophical Investigations. Blackwell: Oxford, UKGoogle Scholar
Wojciechowska, JI and Hewson, CJ 2005 Quality-of-life-assessment in pet dogs. Journal of the American Veterinary Medical Association 226: 722–728CrossRefGoogle ScholarPubMed
Woolf, CJ and Salter, MW 2000 Neuronal plasticity: increasing the gain in pain. Science 288: 1765–1768CrossRefGoogle ScholarPubMed
Yeates, JW and Main, DCJ 2008 Assessment of positive welfare: a review. The Veterinary Journal 175: 293–300CrossRefGoogle ScholarPubMed
Yeates, JW and Main, DCJ 2009 Assessment of companion animal quality of life in veterinary practice and research. Journal of Small Animal Practice 50(6): 274–283CrossRefGoogle ScholarPubMed
Zald, DH and Depue, RA 2001 Serotonergic functioning correlates with positive and negative affect in psychiatrically healthy males. Personality and Individual Differences 30: 71–86CrossRefGoogle Scholar