Our ability to assess pain in animals in clinical situations is slowly developing, but remains very limited. In order to develop appropriate pain scoring schemes, numerous practical problems need to be overcome. In addition, we need to appraise realistically our current poor state of knowledge. Development of new scoring systems must be coupled with the increased education and training of those responsible for pain management, so that both the assessment and the alleviation of pain are steadily improved.

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.

A survey was undertaken to evaluate how animal discomfort, pain, suffering and distress are recognised and assessed in UK scientific procedure establishments. In total, twenty-eight establishments were visited between 1999 and 2001 and 137 people participated, including animal technicians, veterinarians and scientists. The full results, conclusions and recommendations of the survey have been published elsewhere (Hawkins 2002). The study showed that people are concerned about animal suffering, want to be able to prevent and alleviate it, and are aware that there are a number of practical problems that need to be overcome. These include animals concealing clinical signs, which leads to difficulties in detecting incipient discomfort and distress, and human subjectivity when assessing animals. The clinical signs used as indicators of potential pain, suffering and distress are largely subjective. Participants at all establishments agree that a ‘team’ approach to animal monitoring is the best way to ensure consistency and effectiveness. All twenty-eight establishments use clinical observation sheets to assist with animal assessment and monitoring, nine also use score sheets and seven use computerised data management systems. This paper concludes with recommendations based on the survey findings, with respect to monitoring techniques, assessment protocols and training issues, which aim to facilitate more effective animal assessment and monitoring.

Lameness is an indicator of pain and suffering, which has substantial animal welfare and economic impact on the dairy industry. Subjective locomotion scoring is unreliable for detecting mild cases of lameness in dairy herds. Undetected lameness can progress to a more serious and painful state with unfavourable prognosis. The aim of this study was to conduct an investigation on the use of a pressure plate for early detection of lameness in dairy heifers compared to a subjective visual scoring system. Seven heifers deemed sound, on the basis of a visual scoring system, were walked through a chute where a pressure plate was disguised on the floor. Claws were then inspected during trimming and revealed no lesions (n = 3) and hairy heel warts on at least one hind claw (n = 4). Peak vertical force (PVF) and right-left hind limb PVF symmetry were calculated. Sound heifers demonstrated significantly higher PVF and better right-left hind limb symmetry than those with hairy heel warts. Using a pressure plate, gait abnormalities from foot lesions that were undiagnosed using a subjective lameness scoring system, were detected. Early detection of lameness is vital to reduce dairy industry losses and to improve animal welfare.

Piglets on commercial pig farms are often tail-docked to reduce the incidence of tail-biting. While this is a painful procedure, piglets are often not provided analgesia or anaesthesia for pain relief. The objectives of this study were to assess a multimodal approach to managing tail-docking pain in piglets, using 0.4 mg kg-1 meloxicam (MEL), 0.04 mg kg-1 buprenorphine (BUP), and Maxilene® (MAX), a topical anaesthetic. The effectiveness of each drug and drug combination was evaluated using behavioural indicators, vocalisation, and facial grimace analysis. This study also assessed whether male and female piglets responded differently to pain or pain treatments. Piglets were randomly assigned to one of six possible treatments: MEL, BUP, MEL + BUP, MEL + BUP + MAX, no treatment (tail-docked control), or sham (non-tail-docked control). Vocalisations were recorded at initial handling, injection, and tail-docking. Piglets administered MEL + BUP and BUP demonstrated significantly fewer pain behaviours than piglets in the MEL and no treatment group. MEL + BUP + MAX and BUP piglets displayed significantly lower facial grimace scores than piglets in the no treatment group. There were no significant differences in emitted vocalisations between the analgesia-treated piglets and the no treatment group and both injection and tail-docking elicited piglet vocalisations of similar frequency, power, and energy. There were no significant differences in behaviour, facial grimacing or emitted vocalisations between male and female piglets. All treatment groups with buprenorphine were able to alleviate tail-docking-associated pain, suggesting that opioid administration is highly effective for managing piglet pain.

Captive bears are prone to developing dental pathology for reasons including longevity in captivity, inappropriate diet, trauma, and stereotypical bar biting. If not detected, this can cause pain and suffering, with negative welfare consequences. As animals cannot verbally express feelings, objective methods are required to detect pain. Some methods of pain assessment can be invasive and impractical but behavioural observations offer a non-invasive alternative. Behavioural assessment for the detection of pain has been described in some domestic species but little published research has applied this to wild animal species. Eight Malayan sun bears (Helarctos malayanus) required dental extractions under anaesthesia. Their behaviour was observed, alongside a control cohort with no visible disease, pre-operatively and at one, two and four weeks post-operatively, when it was assumed the pain had resolved from the original pathology and surgery performed. Behavioural indices measured included general activity, social behaviours, stereotypies, eating-related behaviours and oro-facial behaviours hypothesised to be affected by dental pain. Bears that had received treatment took significantly longer to eat hard sugarcane pre-operatively compared to four weeks post-operatively, and took longer to eat soft porridge one week post-operatively compared to four weeks post-operatively. Untreated bears tended to be more active outdoors one week postoperatively compared to the treatment cohort. Results suggest that using hard foods and assessing the duration of eating behaviours could be useful to indicate dental pain in sun bears. General behavioural assessment of dental pain in sun bears is unlikely to be effective as a single diagnostic tool, but may be combined with other methods of assessment, and further research into this area is warranted.

Surgical castration of piglets is a routine procedure on commercial pig farms, to prevent boar taint and reduce aggression. This procedure is known to cause pain, yet piglets are often not provided appropriate analgesia for relief. The objective of this study was to assess a multimodal approach to managing post-castration pain in piglets, using 0.4 mg kg-1 meloxicam (MEL), 0.04 mg kg-1 buprenorphine (BUP), and Maxilene® (MAX). Efficacy was evaluated using behavioural indicators, vocalisation, and facial grimace analysis. Male piglets were randomly assigned to one of ten possible treatments (n = 15 piglets per treatment group): MEL + BUP + MAX (castrated or uncastrated); MEL + BUP (castrated or uncastrated); BUP + MAX (castrated or uncastrated); MEL + MAX (castrated or uncastrated); saline (castrated control); or sham (uncastrated control). Castrated piglets in the MEL + BUP + MAX, MEL + BUP, and BUP + MAX treatment groups displayed significantly fewer pain behaviours than piglets administered saline. MEL + MAX was insufficient in reducing surgical castration pain behaviours. At 24 h post-procedure, saline and MEL + MAX-castrated piglets displayed significantly more pain behaviours than all other treatment groups and time-points. Facial grimace analysis indicated that MEL + MAX-castrated piglets had significantly higher grimace scores than MEL + BUP (castrated and uncastrated) and BUP + MAX-uncastrated. There were no significant differences in emitted vocalisations between the analgesia-treated and saline-castrated piglets. All treatment groups with buprenorphine were effective in alleviating castration-associated pain behaviours, suggesting that opioid administration is beneficial for managing piglet castration pain.

Stockpeoples’ ability to recognise pain in their livestock, and to respond appropriately, is of utmost importance for animal welfare. Assessment of pain is complex, and attitudes and empathy are thought to play a role in peoples’ responses to the sight of pain. In a separate paper we investigated the dimensionality of Norwegian dairy goat stockpeoples’ goat-oriented attitudes and empathy. This paper investigates how the stockpeople assess and manage pain and disease in goats. The interrelationships between pain perception and provision of veterinary attention were explored, as well as how these two measures are associated with demographics, attitudes and empathy. Pain assessment scores for individual conditions ranged across most of the picture-based pain assessment scale. Dystocia, gangrenous mastitis and the neurological form of caprine arthritis encephalitis were considered most painful. Linear regression showed that one attitude dimension was positively associated with mean pain assessment score (mPAS), while growing up on a goat farm, having farming as main income and having seen a large number of the conditions were negatively associated with mPAS. Cluster analysis on reported frequency of contacting veterinary surgeons for ten conditions revealed two distinct groups of stock-people. Logistic regression showed that females, older stockpeople and stockpeople who grew up in a rural district were significantly more likely to be in the group that more frequently contacted veterinary surgeons. We conclude that training of stockpeople needs to focus on evaluation and management of pain to ensure a high standard of animal welfare.

Given that surgical castration is a painful practice performed on millions of pigs every year, a need to identify novel reliable pain assessment tools exists in order to test anaesthetic and analgesic protocols that may reduce related pain. Two treatments were considered: handling (H) and surgical castration (C). Physiological (cortisol, lactate, glycaemia, rectal and eye temperature) and behavioural variables (latency to move after treatment and alterations in posture and walking) were analysed. Cortisol showed the greatest level in C piglets within 20 min after the surgical procedure and a positive correlation with glucose concentration. Eye temperature was higher in C piglets, and the same difference was detected for rectal temperature 3 h after castration. Behavioural parameters revealed that C piglets had longer latency to move and a higher percentage of them showed alterations in posture and walking. Results of this study showed that, in castrated piglets behavioural and physiological alterations occur mainly in the first 3 h from treatment. Latency to move, alterations in posture and walking, and eye temperature appear to give additional and useful information in piglet pain assessment. However, differently from the behavioural parameters considered, eye temperature involves several manipulations of the animals and a long process to acquire the data.

A research study was conducted at the radiation oncology department of a large teaching hospital in Ghana, to determine whether the use of a pain questionnaire would facilitate a contribution by the radiation therapists (RTs) to the management of pain in the patients undergoing external beam radiotherapy. The rationale for the study was to test the pain questionnaire as a tool for routine use by RTs and to increase the knowledge and skill of the RTs with regard to pain assessment in order that they could have an effective role in the multidisciplinary approach to pain management.

The pain questionnaire for administration by RTs was adapted as a tool for assessing pain. The tool and the process were tested in a prospective study of 90 participants who willingly consented to participate. The data was analysed as a means of evaluating the questionnaire and learning about pain in this group of cancer patients. The results of this analysis were integrated with the findings from textual data published in a previous paper.

Findings revealed that RTs could administer a limited pain questionnaire and use this for clinical assessment of patients with pain, refer patients who need urgent medical attention to the doctors, monitor the patients receiving radiotherapy and adjuvant chemotherapy as well as provide meaningful suggestions to the multidisciplinary team on the management of pain.

Through this reflective process it is recommended that because RTs have daily contact with patients during external beam radiotherapy treatment and because the majority of cancer patients in the study population experience pain, the RTs should enhance their knowledge of pain and participate in routine pain assessment. Through engagement in this role development the quality of care to the patient population in Ghana will be improved.

The aim of this case study is to critically explore the holistic care of a patient who requires pain management in the Post Anaesthetic Care Unit (PACU). The development of chronic pain can have a significant psychological impact as well as a debilitating physical effect. The article examines pain assessment tools used in the PACU as well as barriers to their implementation. Finally, both pharmacological and non-pharmacological holistic care interventions are examined.

Several lines of evidence suggest that mental motor imagery is subserved by the same cognitive operations and brain structures that underlie action. Additionally, motor imagery is informed by the anticipated sensory consequences of action, including pain. We reasoned that motor imagery could provide a useful measure of chronic leg or foot pain. Forty subjects with leg pain (19 bilateral, 11 right, and 10 left leg pain), 42 subjects with chronic pain not involving the legs, and 38 controls were shown 12 different line drawings of the right or left foot and asked to indicate which foot was depicted. Previous work suggests that subjects perform this task by mentally rotating their foot to match the visually presented stimulus. All groups of subjects were slower and less accurate with stimuli that required a greater degree of mental rotation of their foot. Subjects with leg pain were both slower and less accurate than normal and pain control subjects in responding to drawings of a painful extremity. Furthermore, subjects with leg pain exhibited a significantly greater decrement in performance for stimuli that required larger amplitude mental rotations. These data suggest that motor imagery may provide important insights into the nature of the pain experience. (JINS, 2010, 16, 603–612.)