Matthew C. Leach

Matthew C. Leach
Newcastle University | NCL · Comparative Biology Centre

BSc Hons, MSc, PhD

About

115
Publications
107,859
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
3,507
Citations
Citations since 2017
48 Research Items
2677 Citations
20172018201920202021202220230100200300400500
20172018201920202021202220230100200300400500
20172018201920202021202220230100200300400500
20172018201920202021202220230100200300400500
Additional affiliations
August 2012 - present
Newcastle University
Position
  • Animal Science
August 2012 - present
Newcastle University
Position
  • Assessment & alleviation of pain in animals
October 2005 - August 2012
Newcastle University
Position
  • Assessment & alleviation of pain in animals
Education
September 1998 - August 2001
University of Birmingham
Field of study
  • Laboratory Animal Welfare
September 1995 - August 1996
The University of Edinburgh
Field of study
  • Applied Animal Behaviour & Animal Welfare
September 1992 - June 1995
University of Southampton
Field of study
  • Zoology

Publications

Publications (115)
Article
Using food rewards to motivate mice is commonplace in behavioural research. Using a reward which is highly desirable is of benefit, as it can reduce the need to food restrict animals and can encourage higher levels of consumption, allowing for changes in levels of consumption following an intervention to be easily determined. Here, we aimed to dete...
Conference Paper
Full-text available
Mice are the most widely used laboratory species, with millions used annually worldwide. The vast majority of these are killed either during or after the scientific work and, according to current legislation, must be killed humanely. Exposure to a rising concentration of carbon dioxide (CO ) remains the most common method of killing laboratory rode...
Article
Full-text available
Considering the widespread use of rabbits in research that potentially causes pain and discomfort and the limited number of pain assessment validated tools in this species, we aimed to develop and validate a scale of acute postoperative pain in rabbits (RPBS). Footage of 58 rabbits from previous studies were used, recorded at 'baseline' (before ort...
Article
Background: Accurate assessment of the welfare of non-human primates (NHPs) used and bred for scientific purposes is essential for effective implementation of obligations to optimise their well-being, for validation of refinement techniques and novel welfare indicators, and for ensuring the highest quality data is obtained from these animals. Despi...
Article
Full-text available
Millions of mice are used annually in scientific research and must be humanely killed. Despite significant welfare concerns, carbon dioxide exposure remains the most common killing method, primarily because there is no practical and humane alternative. We explored whether hypobaric hypoxia via gradual decompression could induce a non-recovery state...
Article
Background: Accurate assessment of the welfare of non-human primates (NHPs) used and bred for scientific purposes is essential for effective implementation of obligations to optimise their well-being, for validation of refinement techniques and novel welfare indicators, and for ensuring the highest quality data is obtained from these animals. Despi...
Article
Full-text available
Prevention of pain in rabbits is a priority for both welfare and validity of scientific data. We aimed to determine if the rabbit grimace scale (RbtGS) could be used as a viable, rapid assessment tool in two breeds of rabbit, Dutch belted (DB) and New Zealand white (NZW), following orchidectomy, as an adjunct to behavioral analysis. All animals rec...
Article
The goal of this study was to evaluate the effect of a human observer on Rabbit Grimace Scale (RbtGS) scores. The study scored video footage taken of 28 rabbits before and after orthopedic surgery, as follows: 24 h before surgery ( baseline ), 1 h after surgery ( pain ), 3 h after analgesia administration ( analgesia ), and 24 h after surgery ( 24h...
Article
Full-text available
When we treat an animal’s welfare as an individual experience, we should consider the possibility that it may be associated with individual differences in personality. We tested for such associations in 44 socially housed rhesus macaques (Macaca mulatta) that lived at the California National Primate Research Center. For each macaque, we obtained ra...
Article
Full-text available
Despite the importance for both animal welfare and scientific integrity of effective welfare assessment in non-human primates, there has been little or no consensus as what should be assessed. A Delphi consultation process was undertaken to identify the animal- and environment-based measures of welfare for laboratory-housed macaques and to determin...
Article
Full-text available
Rabbits are widely used in studies focusing on pain. However, pain is undertreated in this species and one possible factor to explain this is the lack of evaluation methods. The objective of this study was to identify behaviours related to orthopaedic pain in rabbits and to evaluate the influence of the presence of an observer on these behaviours....
Article
Full-text available
Whether and to what extent animals experience emotions is crucial for understanding their decisions and behaviour, and underpins a range of scientific fields, including animal behaviour, neuroscience, evolutionary biology and animal welfare science. However, research has predominantly focused on alleviating negative emotions in animals, with the ex...
Article
Full-text available
The Horse Grimace Scale (HGS) is a facial-expression-based pain coding system that enables a range of acute painful conditions in horses to be effectively identified. Using valid assessment methods to identify pain in horses is of a clear importance; however, the reliability of the assessment is highly dependent on the assessors’ ability to use it....
Article
To determine whether participation in dog agility has an impact on canine arousal and welfare, this study aimed firstly to identify the effect of the competition context on arousal changes experienced by dogs, as distinct from purely physical participation in agility, and secondly to assess the handlers’ ability to recognize this. Behaviors indicat...
Conference Paper
To develop a valid, reliable, and practical welfare assessment tool, indices thought to reflect an animal’s welfare must be first be identified. Individuals may define and measure welfare differently based on their experiences; thus, using a group consensus approach such as the Delphi method can be a systematic way to identify generalizable welfare...
Article
Full-text available
Effective management of pain is critical to the improvement of animal welfare. For this to happen, pain must be recognised and assessed in a variety of contexts. Pain is a complex phenomenon, making reliable, valid, and feasible measurement challenging. The use of facial expressions as a technique to assess pain in non-verbal human patients has bee...
Article
Full-text available
Abstract This study aims to identify the most valid, reliable and practicable indicators of laboratory mouse welfare using the Delphi consultation technique. The effective assessment of laboratory mouse welfare is a fundamental legal and moral requirement as it is critical part of both maintaining and improving the welfare of the most widely used l...
Article
Effective management of pain is critical to the improvement of animal welfare. For this to happen, pain must be recognised and assessed in a variety of contexts. Pain is a complex phenomenon, making reliable, valid, and feasible measurement challenging. The use of facial expressions as a technique to assess pain in non-verbal human patients has bee...
Article
Full-text available
Being able to assess pain in nonhuman primates undergoing biomedical procedures is important for preventing and alleviating pain, and for developing better guidelines to minimise the impacts of research on welfare in line with the 3Rs principle of Refinement. Nonhuman primates are routinely used biomedical models however it remains challenging to r...
Article
Full-text available
The majority of commentaries are supportive of our position on the scepticism that muddies the waters surrounding fish pain and sentience. There is substantial empirical evidence for pain in fish. Animals' experience of pain cannot be compared to artificial intelligence (AI) because AI can only mimic responses to nociceptive input on the basis of h...
Article
Full-text available
Pain recognition is fundamental for safeguarding animal welfare. Facial expressions have been investigated in several species and grimace scales have been developed as pain assessment tool in many species including horses (HGS) and mice (MGS). This study is intended to progress the validation of grimace scales, by proposing a statistical approach t...
Data
Horse Grimace Scale (HGS) dataset. (TXT)
Data
Mouse Grimace Scale (MGS) dataset. (TXT)
Article
Full-text available
Recent empirical studies have reported evidence that many aquatic species, including fish, cephalopods and crustaceans, have the capacity for nociception and pain, and that their welfare should be taken into consideration. Some sceptics, rejecting the precautionary principle, have denied that any study demonstrates pain or other aspects of sentienc...
Article
Full-text available
Mice are the most widely used model species for drug discovery and scientific research. Consequently, it is important to refine laboratory procedures and practices to ensure high standards of welfare and scientific data quality. Recent studies have identified that the standard practice of handling laboratory mice by their tails increases behaviours...
Article
Full-text available
Reliable recognition of pain is difficult in ferrets as many currently available parameters are non-specific, inconsistent and/or impractical. Grimace scales have successfully been applied to assess pain in different animal species and might also be applicable to ferrets. To compose a Ferret Grimace Scale (FGS), we studied the facial musculature of...
Data
Observer scores for nose bulging. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)
Data
Observer scores for ear changes. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)
Data
Observer scores for orbital tightening. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)
Data
Post-training observer scores for overall pain. 0 = no pain, 1 = mild pain, 2 = moderate pain, 3 = severe pain or? = missing. (XLSX)
Data
Pre-training observer scores for overall pain. 0 = no pain, 1 = mild pain, 2 = moderate pain, 3 = severe pain or? = missing. (XLSX)
Data
Observer scores for cheek bulging. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)
Data
Observer scores for whisker retraction. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)
Article
Full-text available
Tail docking in pigs has the potential for evoking short- as well as long-term physiological and behavioural changes indicative of pain. Nonetheless, the existing scientific literature has thus far provided somewhat inconsistent data on the intensity and the duration of pain based on varying assessment methodologies and different post-procedural ob...
Article
Full-text available
Commercial pigs are frequently exposed to tail mutilations in the form of preventive husbandry procedures (tail docking) or as a result of abnormal behaviour (tail biting). Although tissue and nerve injuries are well-described causes of pain hypersensitivity in humans and in rodent animal models, there is no information on the changes in local pain...
Article
Facilities housing captive animals are full of staff who, every day, interact with the animals under their care. The expertise and familiarity of staff can be used to monitor animal welfare by means of questionnaires. It was the goal of our study to examine the association between chimpanzee (Pan troglodytes) welfare, happiness, and personality. To...
Article
Full-text available
Facial expressions are increasingly being used to assess pain in non-human species, including rodents, horses, and lambs. The development of these species-specific grimace scales has allowed for more rapid pain detection, which can lead to better animal welfare if intervention promptly occurs. For grimace scales to ever be used as a stand-alone mea...
Article
Without the ability to effectively recognise pain and assess its severity in animals, there is no way of assessing the efficacy of analgesia administered. Therefore, we have no way of ensuring that pain is adequately managed. Despite the extensive use of rodents in medical research that often involves the assessment of pain and distress, translatio...
Article
Full-text available
Animal welfare is a key issue for industries that use or impact upon animals. The accurate identification of welfare states is particularly relevant to the field of bioscience, where the 3Rs framework encourages refinement of experimental procedures involving animal models. The assessment and improvement of welfare states in animals is reliant on r...
Data
Full-text available
Animal welfare questionnaire designed by myself and Dr. Matt Leach , which we have used in different animal welfare projects.
Article
Facial expressions are routinely used to assess pain in humans, particularly those who are non-verbal. Recently, there has been an interest in developing coding systems for facial grimacing in non-human animals, such as rodents, rabbits, horses and sheep. The aims of this preliminary study were to: 1. Qualitatively identify facial feature changes i...
Article
Full-text available
Over 234,000 rats were used in regulated procedures in the UK in 2014, many of which may have resulted in some degree of pain. When using animals in research, there is an ethical and legal responsibility to alleviate or at least reduce pain to an absolute minimum. To do this, we must be able to effectively assess pain in an accurate and timely mann...
Data
Data used in analysis and used to generate figures. (XLSX)
Article
Full-text available
Many piglets are exposed to potentially painful husbandry procedures within the first week of life, including tail docking and castration, without the provision of either anesthesia or analgesia. The assessment methods used to evaluate pain experienced by piglets are often affected by low specificity and practical limitations, prompting the investi...
Article
Full-text available
Concerns over interactions between analgesics and experimental outcomes are a major reason for withholding opioids from rats undergoing surgical procedures. Only a fraction of morphine injected intravenously reaches receptors responsible for analgesia in the central nervous system. Intrathecal administration of morphine may represent a way to provi...
Data
Rat Grimace Scale scores and behavioural dataset. (XLSX)
Article
Full-text available
To manage pain effectively in people and animals, it is essential to recognise when pain is present and to assess its intensity. Currently there is very little information regarding the signs of post-surgical pain or its management in guinea pigs. Studies from other rodent species indicate that behaviour-based scoring systems can be used successful...
Data
Manually Scored Data. (XLSX)
Article
Full-text available
Acute laminitis is a common equine disease characterized by intense foot pain, both acutely and chronically. The Obel grading system is the most widely accepted method for describing the severity of laminitis by equine practitioners, however this method requires movement (walk and trot) of the horse, causing further intense pain. The recently devel...
Article
Welfare questionnaires, which allow people who are familiar with individual animals to rate the welfare of the animals, are an underutilised tool. We designed a 12-item welfare questionnaire and tested its reliability and associations with subjective well-being (SWB), locomotor stereotypy, and personality traits. The welfare questionnaire included...
Article
Full-text available
Improving laboratory animal science and welfare requires both new scientific research and insights from research in the humanities and social sciences. Whilst scientific research provides evidence to replace, reduce and refine procedures involving laboratory animals (the '3Rs'), work in the humanities and social sciences can help understand the soc...
Article
Full-text available
The assessment of nociceptive thresholds is employed in animals and humans to evaluate changes in sensitivity potentially arising from tissue damage. Its application on the intact pig tail might represent a suitable method to assess changes in nociceptive thresholds arising from tail injury, such as tail docking or tail biting. The Pressure Applica...
Conference Paper
Full-text available
Introduction: Tail biting is a global welfare problem in the pig industry leading to significant tail injury and potential carcass rejection. The temporal effects of such injuries and subsequent healing are presently unknown, although limb amputation in humans can lead to abnormal neural activity and decreased nociceptive thresholds. In order to ev...
Article
Mice used in biomedical research should have pain reduced to an absolute minimum through refinement of procedures or by the provision of appropriate analgesia. Vasectomy is a common and potentially painful surgical procedure carried out on male mice to facilitate the production of genetically modified mice. The aim of our study was to determine if...
Article
Full-text available
Pain assessment in laboratory animals is an ethical and legal requirement. The mouse grimace scale (MGS) is a new method of pain assessment deemed to be both accurate and reliable, and observers can be rapidly trained to use it. In order for a new pain assessment technique to be effective, we must ensure that the score awarded by the technique is o...
Article
Full-text available
Medical research has a heavy and continuing demand for rodent models across a range of disciplines. Behavioural assessment of pain in such models is highly time consuming, thus limiting the number of models and analgesics that can be studied. Facial expressions are widely used to assess pain in human infants. Recently the mouse grimace scale (MGS)...
Article
Full-text available
Prevention or alleviation of pain in laboratory mice is a fundamental requirement of in vivo research. The mouse grimace scale (MGS) has the potential to be an effective and rapid means of assessing pain and analgesic efficacy in laboratory mice. Preliminary studies have demonstrated its potential utility for assessing pain in mouse models that inv...
Article
Intestinal mucositis is a frequent side-effect of chemotherapy treatment. Many oncological research programs aim to identify novel treatments for this distressing condition, and these programs frequently use rat models. Little is known about the presence and progression of pain in these models and how this can best be treated by analgesic therapy....
Article
Social housing is recommended where possible for laboratory mice. In order to achieve this, mice must be individually identifiable. Although, various methods are available, permanent identification is often required, such as ear notching. This method is likely to be painful and to date there is limited literature on pain assessment and alleviation...
Article
The detection and assessment of pain in animals is crucial to improving their welfare in a variety of contexts in which humans are ethically or legally bound to do so. Thus clear standards to judge whether pain is likely to occur in any animal species is vital to inform whether to alleviate pain or to drive the refinement of procedures to reduce in...
Conference Paper
Full-text available
Background: Tail docking in pigs as a preventive measure for tail biting is a common husbandry practice that has been associated with immediate behavioural changes indicative of pain (Sutherland & Tucker, 2011). It is not known whether such an early peripheral nerve damage in the docked tail tip may lead to altered pain sensitivity later in life. I...