Pain detection and amelioration in animals on the farm: issues and options

Pain in nonhuman animals is a difficult concept to identify and measure. This article briefly describes the consequences of pain in animals on the farm and explains the reasons for the minimal use of analgesics in farmed animals. Pain can have implications for both animal welfare and economics. The reasons for a low use of analgesics in farmed animals include the lack of recognition of animal pain owing to the apparent lack of anthropomorphically identifiable behavioral changes, concern over human food safety, and lack of research efforts to develop safe analgesics for farm use. Treatment cost relative to the benefits expected is another hindering factor. Interventions to minimize pain must begin with developing objective and practical measures for pain identification and measurement at the farm level. A suggested use of a combination of different behavioral and physiological indicators would help to identify pain in animals. To facilitate continued usage of the methodologies on the farm it also is necessary to evaluate the economic implication of the pain alleviation intervention.     

Identifying and preventing pain during and after surgery in farm animals

Pain research in farm animals has focused on routine husbandry procedures such as dehorning; much less known about the pain associated with the other surgeries such as those required for displaced abomasum and caesarean delivery. We review the literature on pain in farm animals due to non-routine procedures including laporatomy, caesarean sections, ovariectomy and ovariohysterectomy, displaced abomasums, cannulations, vasectomy and claw removal. Where there are gaps in the farm animal literature, we describe relevant studies on wildlife, companion and lab animals. This review addresses both pain responses during surgery and the pain that animals experience in the hours and days that follow. Surgical procedures sometimes cause pain responses due to damage of somatic tissues (skin, muscle, joints, etc.) and the viscera, and there is some evidence that these pain responses differ. Overall conclusions from this review are that surgical pain in farm animals is under studied, and the resulting lack of knowledge, awareness, assessment tools and treatment protocols means that both intra-operative and post-operative pain are often under treated.     

Identifying and monitoring pain in farm animals: a review

One important objective for animal welfare is to maintain animals free from pain, injury or disease. Therefore, detecting and evaluating the intensity of animal pain is crucial. As animals cannot directly communicate their feelings, it is necessary to identify sensitive and specific indicators that can be easily used. The aim of the present paper is to review relevant indicators to assess pain in several farm species. The term pain is used for mammals, birds and fish, even though the abilities of the various species to experience the emotional component of pain may be different. Numerous behavioural changes are associated with pain and many of them could be used on farms to assess the degree of pain being experienced by an animal. Pain, as a stressor, is associated with variations in the hypothalamic–pituitary–adrenal axis as well as in the sympathetic and immune systems that can be used to identify the presence of pain rapidly after it started. However, most of these measures need sophisticated equipment for their assessment. Therefore, they are mainly adapted to experimental situations. Injuries and other lesional indicators give information on the sources of pain and are convenient to use in all types of situations. Histopathological analyses can identify sources of pain in experimental studies. When pronounced and/or long lasting, the pain-induced behavioural and physiological changes can decrease production performance. Some indicators are very specific and sensitive to pain, whereas others are more generally related to stressful situations. The latter can be used to indicate that animals are suffering from something, which may be pain. Overall, this literature review shows that several indicators exist to assess pain in mammals, a few in birds and very few in fish. Even if in some cases, a single indicator, usually a behavioural indicator, may be sufficient to detect pain, combining various types of indicators increases sensitivity and specificity of pain assessment. Research is needed to build and validate new indicators and to develop systems of pain assessment adapted to each type of situation and each species.     

Companion-Animals’ Effectiveness in Managing Chronic Pain in Adult Community Members

ABSTRACT

Therapy animals have been found to alleviate pain in healthcare settings, but companion-animal owners report greater discomfort and use more analgesics than people who do not own one or more companion animals. To investigate this anomaly, 173 adults completed an online survey that included questions about themselves and any companion animal they owned, the Depression Anxiety and Stress Scales, the Numeric Pain Rating Scale, and a modified version of the Chronic Pain Coping Inventory-42. Participants were also invited to contact the researchers to expand on their responses in a semi-structured interview, to which seven owners responded. There was no significant difference between reported pain levels in owners versus non-owners. However, companion-animal owners who reported actively using human–animal interactions to manage their pain rated this as moderately helpful and reported lower pain levels than other owners. There were also no significant differences between owners’ and non-owners’ anxiety or stress levels. Companion-animal owners reported more depressive symptoms than non-owners, but owners with animals perceived as more friendly reported fewer depressive symptoms. Dog owners comprised most of the sample and, for these participants, there was a negative association between perceived dog friendliness and levels of depression and anxiety. Those with more disobedient dogs also experienced greater stress. Interviewees reported that their companion animals helped them cope with pain in many ways, including provision of social and emotional support and by providing a sense of purpose in life. These findings indicate that some, but not all, companion animals may be beneficial for participants with chronic pain. Since the benefits appear to be associated with the species and personality of the animal, and with whether the person actively uses human–animal interactions as a pain-coping mechanism, care should be taken before recommending companion-animal ownership to persons suffering from chronic pain.     

Genetic Engineering and Other Factors That Might Affect Human-Animal Interactions in the Research Setting

Evidence exists, particularly in the welfare literature of nonhuman animals on the farm, that the interaction between nonhuman animals and the personnel who care for them can have a strong effect on the animals' behavior, productivity, and welfare. Among species commonly used for biomedical research, mice appear to be the least-preferred species in animal care facilities. A review of the literature and observations of animal care staff interacting with mice indicated that the following factors may influence this: their small size, their particular behavioral characteristics, and husbandry constraints (such as housing in ventilated racks). In addition, this study questioned whether animal care personnel have a different perception of genetically engineered animals and whether this, in turn, has an effect on their interactions with these animals. The ability to carefully observe an animal's behavior is key in carrying out an animal-wellness assessment and in minimizing pain and distress. Attention to human-animal interactions in the research setting represents an opportunity for refinement for large numbers of animals and potentially for reduction of animal use.     

Genetic engineering and other factors that might affect human-animal interactions in the research setting

Evidence exists, particularly in the welfare literature of nonhuman animals on the farm, that the interaction between nonhuman animals and the personnel who care for them can have a strong effect on the animals' behavior, productivity, and welfare. Among species commonly used for biomedical research, mice appear to be the least-preferred species in animal care facilities. A review of the literature and observations of animal care staff interacting with mice indicated that the following factors may influence this: their small size, their particular behavioral characteristics, and husbandry constraints (such as housing in ventilated racks). In addition, this study questioned whether animal care personnel have a different perception of genetically engineered animals and whether this, in turn, has an effect on their interactions with these animals. The ability to carefully observe an animal's behavior is key in carrying out an animal-wellness assessment and in minimizing pain and distress. Attention to human-animal interactions in the research setting represents an opportunity for refinement for large numbers of animals and potentially for reduction of animal use.     

Barriers to assessment and treatment of pain in laboratory animals

Pain is an undesirable potential consequence of many of the procedures conducted on animals in the course of scientific research, and in most cases it is unnecessary. The US Congress, the public, and laboratory animal medical professionals have indicated that pain should be prevented or minimized in laboratory animals, yet there is ample evidence to suggest that unalleviated pain is still a problem for some laboratory animals. This evidence is circumstantial to some extent but has its basis in problematic issues of pain control in both veterinary and human medicine. The author attempts to identify specific barriers to reduction of pain in laboratory animals. She then seeks to determine the relative importance of each obstacle and to develop approaches to overcoming each obstacle.     

Animal board invited review: OneARK: Strengthening the links between animal production science and animal ecology

Wild and farmed animals are key elements of natural and managed ecosystems that deliver functions such as pollination, pest control and nutrient cycling within the broader roles they play in contributing to biodiversity and to every category of ecosystem services. They are subjected to global changes with a profound impact on the natural range and viability of animal species, the emergence and spatial distribution of pathogens, land use, ecosystem services and farming sustainability. We urgently need to improve our understanding of how animal populations can respond adaptively and therefore sustainably to these new selective pressures. In this context, we explored the common points between animal production science and animal ecology to identify promising avenues of synergy between communities through the transfer of concepts and/or methodologies, focusing on seven concepts that link both disciplines. Animal adaptability, animal diversity (both within and between species), selection, animal management, animal monitoring, agroecology and viability risks were identified as key concepts that should serve the cross-fertilization of both fields to improve ecosystem resilience and farming sustainability. The need for breaking down interdisciplinary barriers is illustrated by two representative examples: i) the circulation and reassortment of pathogens between wild and domestic animals and ii) the role of animals in nutrient cycles, i.e. recycling nitrogen, phosphorus and carbon through, for example, contribution to soil fertility and carbon sequestration. Our synthesis identifies the need for knowledge integration techniques supported by programmes and policy tools that reverse the fragmentation of animal research toward a unification into a single Animal Research Kinship, OneARK, which sets new objectives for future science policy. At the interface of animal ecology and animal production science, our article promotes an effective application of the agroecology concept to animals and the use of functional diversity to increase resilience in both wild and farmed systems. It also promotes the use of novel monitoring technologies to quantify animal welfare and factors affecting fitness. These measures are needed to evaluate viability risk, predict and potentially increase animal adaptability and improve the management of wild and farmed systems, thereby responding to an increasing demand of society for the development of a sustainable management of systems.     

Use of behavior analysis to recognize pain in small mammals

The minimization of pain in laboratory animals is a gold standard with implications for improvements in both animal welfare and research quality. Changes in behavioral parameters may indicate that an animal is in pain, but in order to effectively use behavioral change to assess pain, the observer must be familiar with normal behaviors. The author discusses normal and pain-related behaviors exhibited by rodents, rabbits, and ferrets.     

Next generation behavioral sequencing for advancing pain quantification

With symptoms such as spontaneous pain and pathologically heightened sensitivity to stimuli, chronic pain accounts for about 20% of physician visits and up to 2/3 of patients are dissatisfied with current treatments. Much of our knowledge on pain processing and analgesics has emerged from behavioral studies performed on animals presenting the same symptoms under pathological conditions. While humans can verbally describe their pain, studies on rodents have relied on behavioral assays providing non-exhaustive characterization or altering animals’ original sensitivity through repetitive stimulations. The emergence of what we term “next-generation behavioral sequencing” is now permitting us to quantitatively describe behavioral features on millisecond to minutes long timescales that lie beyond easy detection with the unaided eye. Here, we summarize emerging videography and computational based behavioral approaches that have the potential to significantly improve pain research.     

Nest Building as an Indicator of Health and Welfare in Laboratory Mice

The minimization and alleviation of suffering has moral and scientific implications. In order to mitigate this negative experience one must be able to identify when an animal is actually in distress. Pain, illness, or distress cannot be managed if unrecognized. Evaluation of pain or illness typically involves the measurement of physiologic and behavioral indicators which are either invasive or not suitable for large scale assessment. The observation of nesting behavior shows promise as the basis of a species appropriate cage-side assessment tool for recognizing distress in mice. Here we demonstrate the utility of nest building behavior in laboratory mice as an ethologically relevant indicator of welfare. The methods presented can be successfully used to identify thermal stressors, aggressive cages, sickness, and pain. Observation of nest building behavior in mouse colonies provides a refinement to health and well-being assessment on a day to day basis.     

Comparative mapping in farm animals.

This paper summarises the current status of comparative mapping in farm animals. For most of the major farm animal species, a wide range of genomic tools are now available to create high-resolution genetic and physical maps of the genome. For many farm animals, the use of radiation hybrid panels and sequence data from expressed sequence tag (EST) projects has accelerated the development of high-resolution comparative maps, with human--the model species for farm animals. These tools and comparative maps are being used to map and identify the genes at the loci for simple and complex traits. The development of detailed physical maps in farm animals based on radiation hybrid panels and bacterial artificial chromosome (BAC) contigs provides a direct link between the 'information-poor' maps of farm animals and the 'information-rich' genomes of human and other model organisms.     

Thirty years after Brambell: whither animal welfare science?

It has been just over 30 years since the Brambell Committee issued its clarion call for research on the welfare of animals used in agriculture. What progress has farm animal welfare science made in those 30 years, and what challenges will it face in the next 30? In this article, I discuss the ways in which the Brambell report, with its emphasis on behavioral needs and suffering, both propelled and constrained the development of animal welfare science. The role that economic factors play and the ways in which they have imposed other kinds of constraints on scientists working with farm animals are also mentioned. Despite these constraints, animal welfare science has contributed to a number of significant improvements in the welfare of farm animals. There is, however, a growing sense that animal welfare science has reached an impasse and that ethical and scientific questions about animal welfare have become hopelessly entangled. In this context, I address what I view to be the principal challenge facing farm animal welfare science, namely to move the issue of beyond suffering to an evaluation of broader quality-of-life questions and their application to improvements in welfare.     

Animal cloning applications and issues

Significant progress in the field of biotechnology has allowed for the use of cloning in animals which is being used: to improve genetic makeup, to rescue endangered species, in tissue engineering and to increase farm animal population. Unfortunately, cloning has been met with failure due to a variety of reasons namely early and late abortions, compromised immune systems, circulatory and respiratory problems and a high rate of fetal death. The reasons of these problems are unknown, but may research groups are attempting to understand the underlying molecular and cellular mechanisms involved in cloning efficiency. Atypical epigenetic re-programming appears to be the primary cause of ineffective cloning. Understanding molecular mechanisms involving key regulatory proteins is pivotal in the success of animal cloning. This review shows the current paradigm involving animal cloning efficiency, and also further elucidates applications to improve animal cloning efficiency.     

Expression stability of commonly used reference genes in canine articular connective tissues

Background

Pain of mild to moderate grade is difficult to detect in laboratory mice because mice are prey animals that attempt to elude predators or man by hiding signs of weakness, injury or pain. In this study, we investigated the use of telemetry to identify indicators of mild-to-moderate post-laparotomy pain.

Results

Adult mice were subjected to laparotomy, either combined with pain treatment (carprofen or flunixin, 5 mg/kg s/c bid, for 1 day) or without pain relief. Controls received anesthesia and analgesics or vehicle only. Telemetrically measured locomotor activity was undisturbed in all animals, thus confirming that any pain experienced was of the intended mild level. No symptoms of pain were registered in any of the groups by scoring the animals' outer appearance or spontaneous and provoked behavior. In contrast, the group receiving no analgesic treatment after laparotomy demonstrated significant changes in telemetry electrocardiogram recordings: increased heart rate and decreased heart rate variability parameters pointed to sympathetic activation and pain lasting for 24 hours. In addition, core body temperature was elevated. Body weight and food intake were reduced for 3 and 2 days, respectively. Moreover, unstructured cage territory and destroyed nests appeared for 1–2 days in an increased number of animals in this group only. In controls these parameters were not affected.

Conclusion

In conclusion, real-time telemetric recordings of heart rate and heart rate variability were indicative of mild-to-moderate post-laparotomy pain and could define its duration in our mouse model. This level of pain cannot easily be detected by direct observation.     

Assessment of pain in dogs: veterinary clinical studies

Hundreds of thousands of animals are presented to US veterinarians annually for surgery or for evaluation of painful disease. This large population offers the opportunity for clinical research of both acute and chronic pain syndromes. Although there is growing interest by veterinary clinical specialists to explore the nature of animal pain and how best to treat it, this resource is relatively unknown to the pain research community. Computer-assisted collection of behavioral data has created new opportunities for characterizing the pain experience in animal species for the benefit of both animals and humans. This review describes the current state of veterinary clinical pain studies in dogs and an application of computer-assisted behavioral analysis.     

The Relationship between Empathy,Perception of Pain and Attitudes toward Pets among Norwegian Dog Owners

ABSTRACT

Anthropomorphism, attachment level, and belief in animal mind, as well as owners' level of empathy and attitudes toward their pets, are some of the factors that affect human–animal interactions. Owners' ability to identify painful conditions in their pets may have important consequences for the welfare of these animals. In addition to characterizing the typical Norwegian dog owner, the aim of this work was to study the relationship between empathy, attitudes, and perceived animal pain. A sample of 3,413 dog owners in Norway received an internet-based questionnaire (QuestBack?), to which1896 responded. The questionnaire included four parts: demographics, the Pet Attitude Scale (PAS), the Animal Empathy Scale (AES), and the Pain Assessment Instrument (PAI). For the PAI, participants were presented with 17 photos, showing dogs experiencing painful situations of varying degrees, and were asked to rate the level of pain they believed each animal was enduring, using a Visual Analogue Scale (VAS). Results showed that Norwegian dog owners had very high levels of animal-directed empathy and equally high levels of positive attitudes toward pets. There were differences based on gender, childhood pet keeping, income and education. Differences were also found rooted in owners' use of their dog, whether kept for companionship or hunting, as well as household size, an indication of human social relations. A strong, positive correlation (r = 0.58) was found between animal-directed empathy and positive attitudes toward pets. Empathy was found to be the best predictor of how people rated pain in dogs. The correlations were, however, moderate, indicating that other processes are also involved when observing animals in pain.     

Ethics and invertebrates: a cephalopod perspective

This paper first explores 3 philosophical bases for attitudes to invertebrates, Contractarian/Kantian, Utilitarian, and Rights-based, and what they lead us to conclude about how we use and care for these animals. We next discuss the problems of evaluating pain and suffering in invertebrates, pointing out that physiological responses to stress are widely similar across the animal kingdom and that most animals show behavioral responses to potentially painful stimuli. Since cephalopods are often used as a test group for consideration of pain, distress and proper conditions for captivity and handling, we evaluate their behavioral and cognitive capacities. Given these capacities, we then discuss practical issues: minimization of their pain and suffering during harvesting for food; ensuring that captive cephalopods are properly cared for, stimulated and allowed to live as full a life as possible; and, lastly, working for their conservation.     

宠物的福利和管理

＂家庭动物＂或＂伴侣动物＂的提法较＂宠物＂而言,更为确切并规范。伴侣动物往往因为种种原因成为城镇的流浪动物,在一定程度上,已经成为社会问题。遗弃宠物的原因尽管多种多样,深层次原因主要还是伦理道德的缺失。流浪动物日益泛滥,正在拷问人类的精神文明,有必要引起全社会的关注。动物福利在当今社会已不仅仅是概念化的一般性号召,一些发达国家出版的动物法典对犬、猫的福利有专题阐述。法典不仅对伴侣动物的各种福利条件作了具体规定,同时还提出了最低标准和最佳方案。本文以犬的食物饲喂、饮水及犬舍的要求为例,逐一介绍。     

Report of the Working Group on Animal Distress in the Laboratory

Finding ways to minimize pain and distress in research animals is a continuing goal in the laboratory animal research field. Pain and distress, however, are not synonymous, and measures that alleviate one may not affect the other. Here, the authors provide a summary of a meeting held in February 2004 that focused on distress in laboratory animals. They discuss the difficulties associated with defining 'distress,' propose methods to aid in recognizing and alleviating distressful conditions, and provide recommendations for animal research conduct and oversight that would minimize distress experienced by laboratory animals.