Hostname: page-component-745bb68f8f-cphqk Total loading time: 0 Render date: 2025-01-25T21:13:39.012Z Has data issue: false hasContentIssue false
  • English
  • Français

Assessing Pain in Animals

Published online by Cambridge University Press:  11 January 2023

K M D Rutherford
K M D Rutherford*
Affiliation:
University of Edinburgh Animal Welfare Research Group, Roslin Biocentre, Roslin, Midlothian EH25 9PS, Scotland, UK
*
kenneth.rutherford@bbsrc.ac.uk
Get access Rights & Permissions [Opens in a new window]

Abstract

Assessing the experience of pain in animals is a difficult task, yet one that is important in animal welfare research. Some approaches to pain assessment in animals are reviewed here. General qualities of pain scales and specific parameters suitable for clinical and experimental pain assessments are discussed. It is argued that pain assessment will progress through an integration of objective and subjective observations of behaviour coupled with multiple measures in various other areas. Such multidimensional pain scales allow an adequate characterisation of the complexity of an individual animal's pain experience to be made. This knowledge improves the recognition and treatment of pain and will allow informed moral debate on the acceptability of practices such as castration and tail-docking of lambs.

Keywords

animal painanimal welfarebeak trimmingcanine ovariohysterectomylamb castrationpain assessment
Type
Research Article
Information
Animal Welfare , Volume 11 , Issue 1 , February 2002 , pp. 31 - 53
Copyright
© 2002 Universities Federation for Animal Welfare

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

Present address: Welfare Biology Group, Roslin Institute (Edinburgh), Roslin, Midlothian, EH25 9PS, Scotland, UK

References

Abu-Saad, H H 1998 Assessment of pain in infants. Research and Clinical Forums 20: 31–41Google Scholar
Anand, K J S, Coskun, V, Thrivikraman, K V, Nemeroff, C B and Plotsky, P M 1999 Long-term behavioral effects of repetitive pain in neonatal rat pups. Physiology & Behavior 66: 627–637CrossRefGoogle ScholarPubMed
Anand, K J S and Craig, K D 1996 New perspectives on the definition of pain. Pain 67: 3–6Google Scholar
Bateson, P 1991 Assessment of pain in animals. Animal Behaviour 42: 827–839CrossRefGoogle Scholar
Baumans, V, Brain, P F, Brugere, H, Clausing, P, Jeneskog, T and Perretta, G 1994 Pain and distress in laboratory rodents and lagomorphs: report of the federation-of-European-laboratory-animal-science-associations (FELASA) working group on pain and distress accepted by the FELASA board of management, November 1992. Laboratory Animals 28: 97–112CrossRefGoogle Scholar
Beerda, B, Schilder, MBH, Janssen, N S C R M and Mol, J A 1996 The use of saliva Cortisol, urinary Cortisol and catecholamine measurements for a noninvasive assessment of stress responses in dogs. Hormones and Behavior 30: 272–279CrossRefGoogle ScholarPubMed
Bennett, G J 1994 Neuropathic pain. In: Wall, P D and Melzack, R (eds) Textbook of Pain, 3rd Edition pp 201–224. Churchill Livingstone: Edinburgh, UKGoogle Scholar
Benson, G J, Grubb, T L, NeffDavis, C, Olson, W A, Thurmon, J C, Lindner, D L, Tranquilli, W J and Vanio, O 2000 Perioperative stress response in the dog: effect of pre-emptive administration of medetomidine. Veterinary Surgery 29: 85–91CrossRefGoogle ScholarPubMed
Berkenbosch, F 1994 Neuroendocrine responses to physical trauma. In: Rothwell, N J and Berkenbosch, F (eds) Brain Control of Responses to Trauma pp 239–259. Cambridge University Press: Cambridge, UKCrossRefGoogle Scholar
Beyer, J E and Wells, N 1989 The assessment of pain in children. The Pediatric Clinics of North America 36: 837–854CrossRefGoogle ScholarPubMed
Bonica, J J 1953 The Management of Pain. Lea & Febiger: Philadelphia, USAGoogle ScholarPubMed
Breward, J and Gentle, M J 1985 Neuroma formation and abnormal afferent nerve discharges after partial beak amputation (beak trimming) in poultry. Experientia 41: 1132–1134CrossRefGoogle ScholarPubMed
Caine, N G 1992 Humans as predators: observational studies and the risk of pseudohabituation. In: Davis, H and Balfour, H (eds) The Inevitable Bond: Examining Scientist-Animal Interactions pp 357–364. Cambridge University Press: Cambridge, UKGoogle Scholar
Capner, C A, Lascelles, B D X and Waterman-Pearson, A E 1999 Current British veterinary attitudes to perioperative analgesia for dogs. Veterinary Record 145: 95–99CrossRefGoogle ScholarPubMed
Caro, T M, Roper, R, Young, M and Dank, G R 1979 Inter-observer reliability. Behaviour 69: 303–315Google Scholar
Chapman, C R, Casey, K L, Dubner, R, Foley, K M, Gracely, R H and Reading, A E 1985 Pain measurement: an overview. Pain 22: 1–31CrossRefGoogle ScholarPubMed
Church, D B, Nicholson, A I, Ilkiw, J E and Emslie, D R 1994 Effect of non-adrenal illness, anaesthesia and surgery on plasma Cortisol concentrations in dogs. Research in Veterinary Science 56: 129–131CrossRefGoogle ScholarPubMed
Clark, R W 1994 Central control of pain. In: Rothwell, N J and Berkenbosch, F (eds) Brain Control of Responses to Trauma pp 295–331. Cambridge University Press: Cambridge, UKCrossRefGoogle Scholar
Colpaert, F C 1987 Evidence that adjuvant arthritis in the rat is associated with chronic pain. Pain 28: 201–222CrossRefGoogle ScholarPubMed
Conzemius, M G, Hill, C M, Sammarco, J L and Perkowski, S Z 1997 Correlation between subjective and objective measures used to determine severity of postoperative pain in dogs. Journal of the American Veterinary Medical Association 210: 1619–1622Google ScholarPubMed
Cottrell, D F and Molony, V 1995 Afferent activity in the superior spermatic nerve of lambs — the effects of application of rubber castration rings. Veterinary Research Communications 19: 503–515CrossRefGoogle ScholarPubMed
Cousins, M and Power, I 1999 Acute and postoperative pain. In: Wall, P D and Melzack, R (eds) Textbook of Pain, 4th Edition pp 447–491. Churchill Livingstone: Edinburgh, UKGoogle Scholar
Danbury, T C, Chambers, J P, Weeks, C A, Waterman, A E and Kestin, SC 1997 Self-selection of analgesic drugs by broiler chickens. In: Forbes, J M, Lawrence, T L J, Rodway, R G and Varley, M A (eds) Animal Choices pp 126–128. British Society of Animal Science: Penicuik, UKGoogle Scholar
Danbury, T C, Weeks, C A, Chambers, J P, Waterman-Pearson, A E and Kestin, S C 2000 Self-selection of the analgesic drug carprofen by lame broiler chickens. Veterinary Record 146: 307–311CrossRefGoogle ScholarPubMed
Dantzer, R 1986 Assessing pain by studying neuroendocrine responses. In: Duncan, I J H and Molony, V (eds) Assessing Pain in Farm Animals pp 39–46. Commission of the European Communities: LuxembourgGoogle Scholar
Dawkins, M S 1998 Evolution and animal welfare. Quarterly Review of Biology 73: 305–328CrossRefGoogle ScholarPubMed
Devey, J J and Crowe, D T 1997 The physiological response to trauma. Compendium on Continuing Education for the Practicing Veterinarian 19: 962–975Google Scholar
Doubell, T P, Mannion, R J and Woolf, C J 1999 The dorsal horn: state-dependent sensory processing, plasticity and the generation of pain. In: Wall, P D and Melzack, R (eds) Textbook of Pain, 4th Edition pp 165–181. Churchill Livingstone: Edinburgh, UKGoogle Scholar
Dubner, R and Ren, K 1999 Assessing transient and persistent pain in animals. In: Wall, P D and Melzack, R (eds) Textbook of Pain, 4th Edition pp 359–369. Churchill Livingstone: Edinburgh, UKGoogle Scholar
Duggan, A W 1992 Inhibition of nociception: pathways and mechanisms. In: Kuchel, T R, Rose, M and Burrell, J (eds) Animal Pain: Ethical and Scientific Perspectives pp 32–35. Australian Council on the Care of Animals in Research and Teaching: Glen Osmond, SA, AustraliaGoogle Scholar
Duncan, I J H, Slee, G S, Seawright, E and Breward, J 1989 Behavioural consequences of partial beak amputation (beak trimming) in poultry. British Poultry Science 30: 479–488CrossRefGoogle ScholarPubMed
Fields, H L and Basbaum, A I 1999 Central nervous system mechanisms of pain modulation. In: Wall, P D and Melzack, R (eds) Textbook of Pain, 4th Edition pp 309–329. Churchill Livingstone: Edinburgh, UKGoogle Scholar
Firth, A M and Haldane, S L 1999 Development of a scale to evaluate postoperative pain in dogs. Journal of the American Veterinary Medical Association 214: 651–659Google ScholarPubMed
Fishbain, D A, Cutler, R, Rosomoff, H L and Rosomoff, R S 1997 Chronic pain-associated depression: antecedent or consequence of chronic pain? A review. Clinical Journal of Pain 13: 116–137CrossRefGoogle ScholarPubMed
Flecknell, P A 1996 Laboratory Animal Anaesthesia: A Practical Introduction for Research Workers and Technicians, 2nd Edition. Academic Press: London, UKGoogle Scholar
Flecknell, P A and Molony, V 1997 Pain and injury. In: Appleby M C and Hughes B 0 (eds) Animal Welfare pp 63–73. CAB International: Wallingford, UKGoogle Scholar
Fox, S M, Mellor, D J, Firth, E C, Hodge, H and Lawoko, C R O 1994 Changes in plasma Cortisol concentrations before, during and after anaesthesia and anaesthesia plus ovariohysterectomy in bitches. Research in Veterinary Science 57: 110–118CrossRefGoogle ScholarPubMed
Fox, S M, Mellor, D J, Lawoko, C R O, Hodge, H and Firth, EC 1998 Changes in plasma Cortisol concentrations in bitches in response to different combinations of halothane and butorphanol, with or without ovariohysterectomy. Research in Veterinary Science 65: 125–133CrossRefGoogle ScholarPubMed
Fox, S M, Mellor, D J, Stafford, K J, Lowoko, C R O and Hodge, H 2000 The effects of ovariohysterectomy plus different combinations of halothane anaesthesia and butorphanol analgesia on behaviour in the bitch. Research in Veterinary Science 68: 265–274CrossRefGoogle ScholarPubMed
Fraser, A F and Broom, D M 1997 Farm Animal Behaviour and Welfare, 3rd Edition. CAB International: Wallingford, UKGoogle Scholar
French, N P and Morgan, K L 1992 Neuromas in docked lambs tails. Research in Veterinary Science 52: 389–390CrossRefGoogle ScholarPubMed
French, N P, Wall, R and Morgan, K L 1994 Lamb tail docking: a controlled field study of the effects of tail amputation on health and productivity. Veterinary Record 134: 463–467CrossRefGoogle Scholar
Gentle, M J 1986a Beak trimming in poultry. World's Poultry Science Journal 42: 268–275CrossRefGoogle Scholar
Gentle, M J 1986b Neuroma formation following partial beak amputation (beak trimming) in the chicken. Research in Veterinary Science 44: 383–385CrossRefGoogle Scholar
Gentle, M J 1991 The acute effects of amputation on peripheral trigeminal afferents in Gallus gallus var. domesticus. Pain 46: 97–103CrossRefGoogle ScholarPubMed
Gentle, M J 1992 Pain in birds. Animal Welfare 1: 235–247Google Scholar
Gentle, M J and Corr, S A 1995 Endogenous analgesia in the chicken. Neuroscience Letters 201: 211–214CrossRefGoogle ScholarPubMed
Gentle, M J, Hughes, B O, Fox, A and Waddington, D 1997 Behavioural and anatomical consequences of two beak trimming methods in 1- and 10-d-old domestic chicks. British Poultry Science 38: 453–463CrossRefGoogle ScholarPubMed
Gentle, M J, Hunter, L N and Waddington, D 1991 The onset of pain-related behaviours following partial beak amputation in the chicken. Neuroscience Letters 128: 113–116CrossRefGoogle ScholarPubMed
Gentle, M J and Seawright, E 1988 The effects of partial beak amputation on circulating leucocytes in the domestic fowl. Medical Science Research 16: 145–146Google Scholar
Gentle, M J and Tilston, V L 1999 Reduction in peripheral inflammation by changes in attention. Physiology & Behavior 66: 289–299CrossRefGoogle ScholarPubMed
Gentle, M J, Waddington, D, Hunter, L N and Jones, R B 1990 Behavioural evidence for persistent pain following partial beak amputation in chickens. Applied Animal Behaviour Science 27: 149–157CrossRefGoogle Scholar
Glatz, P C and Lunam, C A 1994 Production and heart-rate responses of chickens beak trimmed at hatch or at 10 or 42 days of age. Australian Journal of Experimental Agriculture 34: 443–447CrossRefGoogle Scholar
Glatz, P C, Murphy, L B and Preston, A P 1992 Analgesic therapy of beak-trimmed chickens. Australian Veterinary Journal 69: 18CrossRefGoogle ScholarPubMed
Graham, M J, Kent, J E and Molony, V 1997 Effects of four analgesic treatments on the behavioural and Cortisol responses of 3-week-old lambs to tail docking. The Veterinary Journal 153: 87–97CrossRefGoogle ScholarPubMed
Hansen, B 1997 Through a glass darkly: using behavior to assess pain. Seminars in Veterinary Medicine and Surgery (Small Animal) 12: 61–74CrossRefGoogle Scholar
Hansen, B D, Hardie, E M and Carroll, G S 1997 Physiological measurements after ovariohysterectomy in dogs: what's normal? Applied Animal Behaviour Science 51: 101–109CrossRefGoogle Scholar
Hao, J X, Yu, W and Xu, X-J 1998 Evidence that spinal endogenous opioidergic systems control the expression of chronic pain-related behaviours in spinally injured rats. Experimental Brain Research 118: 259–268CrossRefGoogle ScholarPubMed
Hardie, E M, Hansen, B D and Carroll, G S 1997 Behaviour after ovariohysterectomy in the dog: what's normal? Applied Animal Behaviour Science 51: 111–128CrossRefGoogle Scholar
Hart, B L and Hart, L A 1985 Canine and Feline Behavioural Therapy. Lea & Febiger: Philadelphia, USAGoogle Scholar
Hellyer, P W, Frederick, C, Lacy, M, Salman, M D and Wagner, A E 1999 Attitudes of veterinary medical students, house officers, clinical faculty, and staff toward pain management in animals. Journal of the American Veterinary Medical Association 214: 238–244Google ScholarPubMed
Herzberg, U, Murtaugh, M and Beitz, A J 1994 Chronic pain and immunity — mononeuropathy alters immune-responses in rats. Pain 59: 219–225CrossRefGoogle ScholarPubMed
Holton, L, Reid, J, Scott, E M, Pawson, P and Nolan, A 2001 Development of a behaviour-based scale to measure acute pain in dogs. Veterinary Record 148: 525–531CrossRefGoogle ScholarPubMed
Holton, L L, Scott, E M, Nolan, A M, Reid, J and Welsh, E 1998 Relationship between physiological factors and clinical pain in dogs scored using a numerical rating scale. Journal of Small Animal Practice 39: 469–474CrossRefGoogle ScholarPubMed
Hosie, B D, Carruthers, J and Sheppard, B W 1996 Bloodless castration of lambs: results of a questionnaire. British Veterinary Journal 152: 47–55CrossRefGoogle ScholarPubMed
Iggo, A 1984 Pain In Animals. The Hume Memorial Lecture. Universities Federation for Animal Welfare: Wheathampstead, UKGoogle Scholar
International Association for The Study Of Pain (LASP) 1979 Pain terms: a list with definitions and notes on usage. Pain 6: 249–252Google Scholar
Jackson, R E, Molony, V and Kent, J E 1999 Behavioural effects of chronic neuropathic pain from the tail in lambs. In: Abstracts — 9th World Congress on Pain (Vienna, Austria) p 144. IASP Press: Seattle, USAGoogle Scholar
Jensen, T S and Nikolajsen, L 1999 Phantom pain and other phenomena after amputation. In: Wall, P D and Melzack, R (eds) Textbook Of Pain, 4th Edition pp 799–814. Churchill Livingstone: Edinburgh, UKGoogle Scholar
Kavaliers, M 1988 Evolutionary and comparative aspects of nociception. Brain Research Bulletin 21: 923–931CrossRefGoogle ScholarPubMed
Kavaliers, M and Colwell, D D 1991 Sex differences in opioid and non-opioid mediated predator-induced analgesia in mice. Brain Research 568: 173–177CrossRefGoogle ScholarPubMed
Kent, J E 1992 Acute phase proteins: their use in veterinary diagnosis. British Veterinary Journal 148: 279282CrossRefGoogle ScholarPubMed
Kent, J E, Jackson, R E, Molony, V and Hosie, B D 2000a Effects of pain reduction methods on the chronic inflammatory lesions and behaviour of lambs castrated and tail docked with rubber rings at less than two days of age. The Veterinary Journal 160: 33–41CrossRefGoogle ScholarPubMed
Kent, J E, Molony, V and Graham, M J 1998 Comparison of methods for the reduction of acute pain produced by rubber ring castration or tail docking of week-old lambs. The Veterinary Journal 155: 39–51CrossRefGoogle ScholarPubMed
Kent, J E, Molony, V, Jackson, R E and Hosie, B D 1999 Chronic inflammatory responses of lambs to rubber ring castration: are there any effects of age or size of lamb at treatment? In: Russel A J F, Morgan C A, Savory C J, Appleby M C and Lawrence T L J (eds) Farm Animal Welfare — Who Writes The Rules? pp 160-162. British Society of Animal Science: Penicuik, UKCrossRefGoogle Scholar
Kent, J E, Molony, V and McKendrick, I 2000b Use of principal component analysis and discriminant analysis to simplify the assessment of pain. In: Noldus L P J J (ed) Proceedings of the 3rd International Conference on Methods and Techniques in Behavioral Research (Nijmegen, The Netherlands) pp 181184. Noldus Information Technology: Wageningen, The NetherlandsGoogle Scholar
Kent, J E, Molony, V and Robertson, I S 1993 Changes in plasma Cortisol concentration in lambs of three ages after three methods of castration and tail docking. Research in Veterinary Science 55: 246–251CrossRefGoogle ScholarPubMed
Kyles, A E, Hardie, E M, Hansen, B D and Papich, M G 1998 Comparison of transdermal fentanyl and intramuscular oxymorphone on post-operative behaviour after ovariohysterectomy in dogs. Research in Veterinary Science 65: 245–251CrossRefGoogle ScholarPubMed
Lascelles, B D X, Cripps, P J, Jones, A and Waterman, A E 1997 Post-operative central hypersensitivity and pain: the pre-emptive value of pethidine for ovariohysterectomy. Pain 73: 461–471CrossRefGoogle ScholarPubMed
Lester, S J, Mellor, D J, Holmes, R J, Ward, R N and Stafford, K J 1996 Behavioural and Cortisol responses of lambs to castration and tailing using different methods. New Zealand Veterinary Journal 44: 45–54CrossRefGoogle ScholarPubMed
Ley, S J, Livingston, A and Waterman, A E 1992 Effects of clinically occurring chronic lameness in sheep on the concentrations of plasma noradrenaline and adrenaline. Research in Veterinary Science 53: 122–125CrossRefGoogle ScholarPubMed
Lindh, V, Wiklund, U and Hakansson, S 1999 Heel lancing in term new-born infants: an evaluation of pain by frequency domain analysis of heart rate variability. Pain 80: 143–148CrossRefGoogle ScholarPubMed
Livingston, A 1986 Assessing pain by studying physiological responses. In: Duncan, I J H and Molony, V (eds) Assessing Pain in Farm Animals pp 30–35. Commission of the European Communities: LuxembourgGoogle Scholar
Machin, K L 1999 Amphibian pain and analgesia. Journal of Zoo and Wildlife Medicine 30: 2–10Google ScholarPubMed
Martini, L, Lorenzini, R N, Cinotti, S, Fini, M, Giavaresi, G and Giardino, R 2000 Evaluation of pain and stress levels of animals used in experimental research. Journal of Surgical Research 88: 114–119CrossRefGoogle ScholarPubMed
Mathews, K A 2000 Pain assessment and general approach to management. Veterinary Clinics of North America: Small Animal Practice 30: 729–755CrossRefGoogle ScholarPubMed
McGeown, D, Danbury, T C, Waterman-Pearson, A and Kestin, S C 1999 Effect of carprofen on lameness in broiler chickens. Veterinary Record 144: 668–671CrossRefGoogle ScholarPubMed
McKee, J S and Harrison, P C 1995 Effects of supplemental ascorbic-acid on the performance of broilerchickens exposed to multiple concurrent stressors. Poultry Science 74: 1772–1785CrossRefGoogle Scholar
McMahon, S B 1997 Are there fundamental differences in the peripheral mechanisms of visceral and somatic pain? Behavioral and Brain Sciences 20: 381–391CrossRefGoogle ScholarPubMed
Mellor, D J, Cook, C J and Stafford, K J 2000 Quantifying some responses to pain as a stressor. In: Moberg, G P and Mench, J A (eds) The Biology of Animal Stress: Basic Principles and Implications for Animal Welfare pp 171–198. CAB International: Wallingford, UKCrossRefGoogle Scholar
Mellor, D J and Murray, L 1989 Effects of tail docking and castration on behavior and plasma-cortisol concentrations in young lambs. Research in Veterinary Science 46: 387–391CrossRefGoogle ScholarPubMed
Mellor, D and Stafford, K 1999 Assessing and minimising the distress caused by painful husbandry procedures in ruminants. In Practice 21: 436–446CrossRefGoogle Scholar
Melzack, R and Scott, T H 1957 The effects of early experience on the response to pain. Journal of Comparative Physiological Psychology 50: 155–161CrossRefGoogle ScholarPubMed
Melzack, R and Wall, P D 1996 The Challenge Of Pain. Penguin Books: London, UKGoogle Scholar
Millan, M J 1999 The induction of pain: an integrative review. Progress in Neurobiology 57: 1–164CrossRefGoogle ScholarPubMed
Mogil, J S 1999 The genetic mediation of individual differences in sensitivity to pain and its inhibition. Proceedings of the National Academy of Sciences of the United States of America 96: 7744–7751CrossRefGoogle ScholarPubMed
Molony, V 1992 Is animal pain the same as human pain? In: Kuchel T R, Rose M, and Burrell J (eds) Animal Pain: Ethical And Scientific Perspectives pp 38–40. Australian Council on the Care of Animals in Research and Teaching: Glen Osmond, SA, AustraliaGoogle Scholar
Molony, V 1997 Comments on Anand and Craig (Pain 67: 3-6). Pain 70: 293CrossRefGoogle ScholarPubMed
Molony, V 1999 Ischaemic visceral pain from castration of lambs. In: Do Animals Have Pain? Satellite Symposium of the 9th World Congress on Pain p 20. International Association for the Study of Pain: Vienna, AustriaGoogle Scholar
Molony, V and Kent, J E 1997 Assessment of acute pain in farm animals using behavioural and physiological measurements. Journal of Animal Science 75: 266–272CrossRefGoogle ScholarPubMed
Molony, V, Kent, J E, Hosie, B D and Graham, M J 1997 Reduction in pain suffered by lambs at castration. The Veterinary Journal 153: 205–213CrossRefGoogle ScholarPubMed
Molony, V, Kent, J E and Robertson, I S 1993 Behavioural responses of lambs of three ages in the first three hours after three methods of castration and tail docking. Research in Veterinary Science 55: 236–245CrossRefGoogle ScholarPubMed
Molony, V, Kent, J E and Robertson, I S 1995 Assessment of acute and chronic pain after different methods of castration of calves. Applied Animal Behaviour Science 46: 33–48CrossRefGoogle Scholar
Möltner, R, Hölzl, R and Strian, F 1990 Heart rate changes as an autonomic component of the pain response. Pain 43: 81–89CrossRefGoogle ScholarPubMed
Morton, D B 1999 Humane endpoints in animal experimentation for biomedical research: ethical, legal and practical aspects. In: Hendriksen, C F M and Morton, D B (eds) Humane Endpoints in Animal Experimentation for Biomedical Research pp 5–12. Royal Society of Medicine Press: London, UKGoogle Scholar
Morton, D B and Griffiths, P H M 1985 Guidelines on the recognition of pain, distress and discomfort in experimental animals and an hypothesis for assessment. Veterinary Record 116: 431–436CrossRefGoogle Scholar
Natelson, B H, Creighton, D, McCarty, R, Tapp, W N, Pitman, D and Ottenweller, J E 1987 Adrenal hormonal indices of stress in laboratory rats. Physiology & Behavior 39: 117–125CrossRefGoogle ScholarPubMed
Niv, D and Devor, M 1998 Transition from acute to chronic pain. In: Aronoff, G M (ed) Evaluation and Treatment of Chronic Pain, 3rd Edition pp 27–45. Williams and Wilkins: London, UKGoogle Scholar
Paul, E S and Podberscek, A L 2000 Veterinary education and students’ attitudes towards animal welfare. Veterinary Record 146: 269–272CrossRefGoogle ScholarPubMed
Pieretti, S, d'Amore, A and Loizzo, A 1991 Long-term changes induced by developmental handling on pain threshold: effects of morphine and naloxone. Behavioral Neuroscience 105: 215–218CrossRefGoogle ScholarPubMed
Quinn, A G, McLelland, J, Essex, T and Farr, P M 1991 Measurement of cutaneous inflammatory reactions using a scanning laser-doppler velocimeter. British Journal of Dermatology 125: 30–37CrossRefGoogle ScholarPubMed
Russell, W M S and Burch, R L 1959 The Principles of Humane Experimental Technique. Methuen: London, UKGoogle Scholar
Sandoe, P, Crisp, R and Holtug, N 1997 Ethics. In: Appleby, M C and Hughes, B O (eds) Animal Welfare pp 3–17. CAB International: Wallingford, UKGoogle Scholar
Sanford, J, Ewbank, R, Molony, V, Tavernor, W D and Uvarov, O 1986 Guidelines for the recognition and assessment of pain in animals. Veterinary Record 118: 334–338Google Scholar
Schwartzkopf-Genswein, K S, Stookey, J M, Crowe, T G and Genswein, BMA 1998 Comparison of image analysis, exertion force, and behavior measurements for use in the assessment of beef cattle responses to hot-iron and freeze branding. Journal of Animal Science 76: 972–979CrossRefGoogle ScholarPubMed
Short, C E 1999 Pain in animals. In: Wall P D and Melzack R (eds) Textbook of Pain, 4th Edition pp 10071015. Churchill Livingstone: Edinburgh, UKGoogle Scholar
Storella, R J, Shi, Y, O'Connor, D M, Pharo, G H, Abrams, J T and Levitt, J 1999 Relief of chronic pain may be accompanied by an increase in a measure of heart rate variability. Anesthesia and Analgesia 89: 448–450Google Scholar
Streiner, D L and Norman, G R 1989 Health Measurement Scales: A Practical Guide to Their Development and Use. Oxford University Press: Oxford, UKGoogle Scholar
Struwe, F J, Gleaves, E W and Douglas, J H 1992 Stress measurements on beak-trimmed and untrimmed pullets. Poultry Science 71: 1154–1162CrossRefGoogle ScholarPubMed
Teasdale, G and Jennet, B 1974 Assessment of coma and impaired consciousness. Lancet II: 81–85CrossRefGoogle Scholar
Thornton, P D and Waterman-Pearson, A E 1999 Quantification of the pain and distress responses to castration in young lambs. Research in Veterinary Science 66: 107–118CrossRefGoogle ScholarPubMed
Vestergaard, K S and Sanotra, G S 1999 Relationships between leg disorders and changes in the behaviour of broiler chickens. Veterinary Record 144: 205–209CrossRefGoogle ScholarPubMed
Wall, P D 1979 On the relation of injury to pain. Pain 6: 253–264CrossRefGoogle ScholarPubMed
Wall, P D 1992 Defining pain in animals. In: Short, C E and VanPoznak, A (eds) Animal Pain pp 63–79. Churchill Livingstone: New York, USAGoogle Scholar
Waterman-Pearson, A 1999 Clinical models of animal pain. In: Do Animals Have Pain? Satellite Symposium of the 9th World Congress on Pain p 3. International Association for the Study of Pain: Vienna, AustriaGoogle Scholar
Weary, D M, Braithwaite, L A and Fraser, D 1998 Vocal response to pain in piglets. Applied Animal Behaviour Science 56: 161–172CrossRefGoogle Scholar
Welsh, E M and Nolan, A M 1995 The effect of abdominal surgery on thresholds to thermal and mechanical stimulation in sheep. Pain 60: 159–166CrossRefGoogle ScholarPubMed
Wemelsfelder, F 1997 The scientific validity of subjective concepts in models of animal welfare. Applied Animal Behaviour Science 53: 75–88CrossRefGoogle Scholar
Wemelsfelder, F, Hunter, E A, Mendl, M T and Lawrence, A B 2000 The spontaneous qualitative assessment of behavioural expressions in pigs: first explorations of a novel methodology for integrative animal welfare measurement. Applied Animal Behaviour Science 67: 193–215CrossRefGoogle ScholarPubMed
Wiepkema, P R and Koolhaas, J M 1993 Stress and animal welfare. Animal Welfare 2: 195–218Google Scholar
Wiseman, M L, Nolan, A M, Reid, J and Scott, E M 2001 Preliminary study on owner-reported behaviour changes associated with chronic pain in dogs. Veterinary Record 149: 423–424CrossRefGoogle Scholar
Wood, G N, Molony, V, Fleetwood-Walker, S M, Hodgson, J C and Mellor, DJ 1991 Effects of local anaesthesia and intravenous naloxone on the changes in behaviour and plasma concentrations of Cortisol produced by castration and tail docking with tight rubber rings in young lambs. Research in Veterinary Science 51: 193–199CrossRefGoogle ScholarPubMed
Woolley, S C and Gentle, M J 1987 Physiological and behavioural responses in the hen (Gallus domesticus) to nociceptive stimulation. Comparative Biochemistry and Physiology A — Physiology 88: 27–31CrossRefGoogle ScholarPubMed
Wylie, L M and Gentle, M J 1998 Feeding-induced tonic pain suppression in the chicken: reversal by naloxone. Physiology & Behavior 64: 27–30CrossRefGoogle ScholarPubMed
Wyn-Jones, G 1988 Equine Lameness. Blackwell Science: Oxford, UKGoogle Scholar
Zimmermann, M 1983 Ethical guidelines for investigations of experimental pain in conscious animals. Pain 16: 109–110CrossRefGoogle ScholarPubMed
Zimmermann, M 1986 Behavioural investigations of pain in animals. In: Duncan, I J H and Molony, V (eds) Assessing Pain in Farm Animals pp 16–27. Commission of the European Communities: LuxembourgGoogle Scholar