The need for a cross-species approach to the study of pain in animals

Evaluation of intramuscular ketoprofen and butorphanol as analgesics in chain dogfish (Scyliorhinus retifer)

“…Comparisons were not made between butorphanol and ketoprofen in unanesthetized individuals, but might have yielded interesting results. Accurate assessment of pain in animals remains quite difficult [Morton and Griffiths, 1986;Paul-Murphy et al, 2004]. Unlike inhalation anesthesia, which is easily titrated, MS-222 is more difficult to titrate, and animals were moved from one concentration to the next in increments of 20 ppm.…”

“…However, little documentation of pain perception and its mediation with analgesic medications in teleosts or elasmobranchs is available. Fish possess many of the same anatomic and biochemical structures responsible for the transmission, mediation, and central processing of nociceptive stimuli in mammals [Beitz, 1992;Paul-Murphy et al, 2004], and research has shown that pain perception is likely to be similar to that of mammals [Pert et al, 1974;Kavaliers, 1988;Gregory, 1999;Stoskopf, 1999;Machin, 2001]. Although fish have been shown to avoid known sources of noxious stimuli [Stoskopf, 1999], some researchers contend that lack of a cerebral cortex prevents ''awareness'' of pain in fish [LaChat, 1996;Rose, 2002].…”

Applied Animal Behaviour: Assessment, Pain and Aggression

“…The International Association for the Study of Pain defines pain as 'an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage' (Paul-Murphy et al 2004). Pain is a potent negative affective state that focuses an animal's attention and biases its behaviour.…”

“…These assessment protocols have been criticised not only for the large variation between different observers, but also for their lack of sensitivity (Mathews 2000). Numeric scales rating pain between 0 and 10, and visual analogue scales marking pain on a ruler on which 0 = No Pain Present and 100 = Worst Pain Imaginable, are generally considered to provide better sensitivity and reliability (Mathews 2000;Paul-Murphy et al 2004). However, the validity of these systems may be questioned owing to a lack of transparency regarding pain parameters considered by observers, and these are weighted in the final score.…”

A Tale of Two Worlds: Public Health Management Decisions in Human Rabies Prevention

“…Pain and stress should be viewed as a continuum across species [10]. It is clear that vertebrates other than humans experience unpleasant sensory stimuli associated with tissue damage.…”