Matthew C. Leach

Newcastle University | NCL · Comparative Biology Centre

As IoT becomes more and more commonplace, it is expanding into many different industries. One of these rapidly growing industries is pet tech, technologies designed to aid with the care of pets, expected to reach a market value of $3.7 billion by 2026. As with all IoT technologies, these devices introduce new security, privacy, and safety risks to...

A new, interactive framework supports the evaluation of in vivo and ex vivo research proposals from a sex inclusive research perspective delivering a traffic light classification, indicating whether a proposal is appropriate, risky, or insufficient with regards to sex inclusion. This tool is designed for use by researchers, (animal) ethical review...

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...

Killing is often an unavoidable and necessary procedure for laboratory mice involved in scientific research, and providing a humane death is vital for public acceptance. Exposure to carbon dioxide (CO 2 ) gas is the most widely used methodology despite well proven welfare concerns. Consequently, the continued use of CO 2 and its globally permitted...

Rodents are the predominant species used for scientific research and must be humanely killed upon completion of the work. In the UK this is regulated by Schedule 1 of the Animals Scientific Procedures Act 1986, which lists permitted methodologies considered capable of humane killing, including overdose of an anaesthetic, exposure to carbon dioxide...

The objective of this study was to develop a fully automated multiple-cow real-time lameness detection system using a deep learning approach for cattle detection and pose estimation that could be deployed across dairy farms. Utilising computer vision and deep learning, the system can analyse simultaneously both the posture and gait of each cow with...

Rabbits typically undergo at least one painful procedure during their lifetime and appropriate methods of assessment are essential to reduce or alleviate pain. Various methods of assessing pain in rabbits have been investigated, with the validity of spontaneous behavior and grimace scale scoring being the most studied to date. Assessment of pain is...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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...

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....

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...

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....

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...

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...

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...

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...

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...

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...

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...

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...

Horse Grimace Scale (HGS) dataset. (TXT)

Mouse Grimace Scale (MGS) dataset. (TXT)

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...

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...

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...

Observer scores for nose bulging. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)

Observer scores for ear changes. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)

Observer scores for orbital tightening. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)

Post-training observer scores for overall pain. 0 = no pain, 1 = mild pain, 2 = moderate pain, 3 = severe pain or? = missing. (XLSX)

Pre-training observer scores for overall pain. 0 = no pain, 1 = mild pain, 2 = moderate pain, 3 = severe pain or? = missing. (XLSX)

Observer scores for cheek bulging. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)

Observer scores for whisker retraction. 0 = not present, 1 = moderately present, 2 = obviously present,? = missing. (XLSX)

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...

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...

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...

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...

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...

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...

Animal welfare questionnaire designed by myself and Dr. Matt Leach , which we have used in different animal welfare projects.

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...

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 used in analysis and used to generate figures. (XLSX)

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...

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...

Rat Grimace Scale scores and behavioural dataset. (XLSX)

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...

Anymaze Data. (XLSX)

Manually Scored Data. (XLSX)

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...

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...

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...

Methodological Details. (DOCX)

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...

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...

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...

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...