{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,29]],"date-time":"2026-10-29T01:34:59Z","timestamp":1793237699502,"version":"4.5.0"},"reference-count":143,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T00:00:00Z","timestamp":1741046400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Vet. Sci."],"abstract":"<jats:p>The growing interest in managing and recognizing pain in animals has led to the search for more sensitive methods to evaluate it, especially because some species conceal any visible changes associated with pain or are not easily assessed. Research has shown that an animal's facial expression changes when exposed to painful stimuli. Thus, developing several pain scales (grimace scales) in species such as horses, cattle, pigs, sheep, donkeys, rabbits, rats, mice, and cats has helped to improve the study of pain in veterinary medicine. The possibility of using facial expression as an indicator of pain is due to the direct relationship between the activation of different regions of the Central Nervous System such as the somatosensory cortex, prefrontal cortex, amygdala, hippocampus, and hypothalamus, and their connections with the motor cortex to elicit motor responses including the movement of facial muscles. The present review aims to discuss the neurobiological association between acute pain and facial expressions in animals. It will analyze the importance of facial expression characterization and the use of grimace scales in farm, companion, and laboratory species.<\/jats:p>","DOI":"10.3389\/fvets.2025.1546719","type":"journal-article","created":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T07:09:13Z","timestamp":1741072153000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":19,"title":["How facial expressions reveal acute pain in domestic animals with facial pain scales as a diagnostic tool"],"prefix":"10.3389","volume":"12","author":[{"given":"Daniel","family":"Mota-Rojas","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandra L.","family":"Whittaker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Genaro A.","family":"Coria-Avila","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julio","family":"Mart\u00ednez-Burnes","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Patricia","family":"Mora-Medina","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriana","family":"Dom\u00ednguez-Oliva","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ismael","family":"Hern\u00e1ndez-Avalos","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adriana","family":"Olmos-Hern\u00e1ndez","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Verduzco-Mendoza","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alejandro","family":"Casas-Alvarado","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Temple","family":"Grandin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2025,3,4]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"371","DOI":"10.1016\/S0065-3454(08)60369-1","article-title":"Welfare, stress, and the evolution of feelings","volume":"27","author":"Broom","year":"1998","journal-title":"Adv Study Behav."},{"key":"B2","doi-asserted-by":"publisher","first-page":"1726","DOI":"10.3390\/ani10101726","article-title":"Grimace scores: tools to support the identification of pain in mammals used in research","volume":"10","author":"Cohen","year":"2020","journal-title":"Animals."},{"key":"B3","doi-asserted-by":"publisher","first-page":"409","DOI":"10.14573\/altex.1607161","article-title":"Facial expression: an under-utilised tool for the assessment of welfare in mammals","volume":"34","author":"Descovich","year":"2017","journal-title":"ALTEX."},{"key":"B4","doi-asserted-by":"publisher","first-page":"451","DOI":"10.30802\/AALAS-CM-19-000042","article-title":"Review of pain assessment methods in laboratory rodents","volume":"69","author":"Turner P","year":"2019","journal-title":"Comp Med."},{"key":"B5","doi-asserted-by":"publisher","first-page":"196","DOI":"10.3390\/ani9040196","article-title":"Development of an automated pain facial expression detection system for sheep (ovis aries)","volume":"9","author":"McLennan","year":"2019","journal-title":"Animals."},{"key":"B6","doi-asserted-by":"publisher","first-page":"998","DOI":"10.1017\/S1751731112002406","article-title":"Identifying and monitoring pain in farm animals: a review","volume":"7","author":"Prunier","year":"2013","journal-title":"Animal."},{"key":"B7","first-page":"p. 329","article-title":"\u201cExpression and the nature of emotion","author":"Ekman","year":"1984"},{"key":"B8","doi-asserted-by":"publisher","first-page":"54","DOI":"10.1177\/1754073912451503","article-title":"Facial expression in nonhuman","volume":"5","author":"Waller","year":"2013","journal-title":"Animals."},{"key":"B9","doi-asserted-by":"publisher","first-page":"20","DOI":"10.1080\/23144599.2019.1641899","article-title":"Maternal behaviour in domestic dogs","volume":"7","author":"Lezama-Garc\u00eda","year":"2019","journal-title":"Int J Vet Sci Med."},{"key":"B10","doi-asserted-by":"publisher","first-page":"43","DOI":"10.1080\/23144599.2019.1680044","article-title":"Review of different methods used for clinical recognition and assessment of pain in dogs and cats","volume":"7","author":"Hernandez-Avalos","year":"2019","journal-title":"Int J Vet Sci Med."},{"key":"B11","doi-asserted-by":"publisher","first-page":"232","DOI":"10.31893\/jabb.20031","article-title":"Neurological modulation of facial expressions in pigs and implications for production","volume":"8","author":"Mota-Rojas","year":"2020","journal-title":"J Anim Behav Biometeorol."},{"key":"B12","doi-asserted-by":"publisher","first-page":"9883","DOI":"10.1038\/s41598-019-46330-5","article-title":"Geometric morphometrics for the study of facial expressions in non-human animals, using the domestic cat as an exemplar","volume":"9","author":"Finka","year":"2019","journal-title":"Sci Rep."},{"key":"B13","doi-asserted-by":"publisher","first-page":"212","DOI":"10.1002\/bies.20719","article-title":"The facial expression musculature in primates and its evolutionary significance","volume":"30","author":"Burrows","year":"2008","journal-title":"BioEssays"},{"key":"B14","doi-asserted-by":"publisher","first-page":"37","DOI":"10.1016\/j.applanim.2014.11.003","article-title":"How do humans represent the emotions of dogs? The resemblance between the human representation of the canine and the human affective space","volume":"162","author":"Konok","year":"2015","journal-title":"Appl Anim Behav Sci."},{"key":"B15","doi-asserted-by":"publisher","first-page":"252","DOI":"10.1016\/j.neubiorev.2016.02.015","article-title":"Facial expression to emotional stimuli in non-psychotic disorders: a systematic review and meta-analysis","volume":"64","author":"Davies","year":"2016","journal-title":"Neurosci Biobehav Rev."},{"key":"B16","doi-asserted-by":"publisher","first-page":"1838","DOI":"10.3390\/ani10101838","article-title":"The utility of grimace scales for practical pain assessment in laboratory animals","volume":"10","author":"Mota-Rojas","year":"2020","journal-title":"Animals."},{"key":"B17","doi-asserted-by":"publisher","first-page":"19312","DOI":"10.1038\/s41598-019-55714-6","article-title":"Differences in facial expressions during positive anticipation and frustration in dogs awaiting a reward","volume":"9","author":"Bremhorst","year":"2019","journal-title":"Sci Rep."},{"key":"B18","doi-asserted-by":"publisher","first-page":"e92281","DOI":"10.1371\/journal.pone.0092281","article-title":"Development of the horse grimace scale (HGS) as a pain assessment tool in horses undergoing routine castration","volume":"9","author":"Dalla Costa","year":"2014","journal-title":"PLoS ONE."},{"key":"B19","doi-asserted-by":"publisher","first-page":"47","DOI":"10.3390\/ani6080047","article-title":"Using the horse grimace scale (HGS) to assess pain associated with acute laminitis in horses (Equus caballus)","volume":"6","author":"Dalla Costa","year":"2016","journal-title":"Animals."},{"key":"B20","doi-asserted-by":"publisher","first-page":"25","DOI":"10.1016\/j.applanim.2015.08.023","article-title":"Pain evaluation in dairy cattle","volume":"171","author":"Gleerup","year":"2015","journal-title":"Appl Anim Behav Sci."},{"key":"B21","doi-asserted-by":"publisher","first-page":"412","DOI":"10.3390\/ani10030412","article-title":"Is the piglet grimace scale (PGS) a useful welfare indicator to assess pain after cryptorchidectomy in growing pigs?","volume":"10","author":"Vullo","year":"2020","journal-title":"Animals."},{"key":"B22","doi-asserted-by":"publisher","first-page":"92281","DOI":"10.13130\/AWIN_sheep_2015","article-title":"Using facial expression to assess pain in sheep","volume":"9","author":"AWIN","year":"2014"},{"key":"B23","doi-asserted-by":"publisher","first-page":"55","DOI":"10.1186\/1744-8069-7-55","article-title":"The rat grimace scale: a partially automated method for quantifying pain in the laboratory rat via facial expressions","volume":"7","author":"Sotocinal","year":"2011","journal-title":"Mol Pain."},{"key":"B24","doi-asserted-by":"publisher","first-page":"447","DOI":"10.1038\/nmeth.1455","article-title":"Coding of facial expressions of pain in the laboratory mouse","volume":"7","author":"Langford","year":"2010","journal-title":"Nat Methods."},{"key":"B25","doi-asserted-by":"publisher","first-page":"e44437","DOI":"10.1371\/journal.pone.0044437","article-title":"Evaluation of EMLA cream for preventing pain during tattooing of rabbits: changes in physiological, behavioural and facial expression responses","volume":"7","author":"Keating","year":"2012","journal-title":"PLoS ONE."},{"key":"B26","doi-asserted-by":"publisher","first-page":"19128","DOI":"10.1038\/s41598-019-55693-8","article-title":"Facial expressions of pain in cats: the development and validation of a feline grimace scale","volume":"9","author":"Evangelista","year":"2019","journal-title":"Sci Rep."},{"key":"B27","doi-asserted-by":"publisher","first-page":"984042","DOI":"10.3389\/fpain.2022.984042","article-title":"Pain modulation in the spinal cord","volume":"3","author":"Woolf","year":"2022","journal-title":"Front Pain Res."},{"key":"B28","doi-asserted-by":"publisher","first-page":"235","DOI":"10.1097\/01.nrl.0000138734.45742.8d","article-title":"The motor cortex and facial expression: new insights from neuroscience","volume":"10","author":"Morecraft","year":"2004","journal-title":"Neurologist."},{"key":"B29","doi-asserted-by":"publisher","first-page":"52","DOI":"10.1016\/S0278-2626(03)00008-3","article-title":"Facial expressions of emotion: a cognitive neuroscience perspective","volume":"52","author":"Erickson","year":"2003","journal-title":"Brain Cogn."},{"key":"B30","doi-asserted-by":"publisher","first-page":"645","DOI":"10.1002\/ar.21355","article-title":"Evolution of the muscles of facial expression in a monogamous ape: evaluating the relative influences of ecological and phylogenetic factors in hylobatids","volume":"294","author":"Burrows","year":"2011","journal-title":"Anat Rec."},{"key":"B31","doi-asserted-by":"crossref","first-page":"p. 88","DOI":"10.1093\/oso\/9780195112719.003.0005","volume-title":"The Expresion of the Emotions in Man and Animals. 3rd Edn","author":"Darwin","year":"1998"},{"key":"B32","doi-asserted-by":"crossref","first-page":"p. 1","DOI":"10.1079\/9781780644035.0000","volume-title":"Sentience and Animal Welfare","author":"Broom","year":"2014"},{"key":"B33","doi-asserted-by":"publisher","first-page":"501","DOI":"10.2174\/1567205013666160603010455","article-title":"Facial pain expression in dementia: a review of the experimental and clinical evidence","volume":"14","author":"Lautenbacher","year":"2016","journal-title":"Curr Alzheimer Res."},{"key":"B34","doi-asserted-by":"publisher","first-page":"260","DOI":"10.1016\/j.jnn.2022.07.025","article-title":"Facial expression as an indicator of neonatal pain in randomized clinical trials: an integrative review","volume":"29","author":"Magesti","year":"2023","journal-title":"J Neonatal Nurs."},{"key":"B35","doi-asserted-by":"publisher","first-page":"173","DOI":"10.3390\/jcm7070173","article-title":"Automatic infants' pain assessment by dynamic facial representation: effects of profile view, gestational age, gender, and race","volume":"7","author":"Zhi","year":"2018","journal-title":"J Clin Med"},{"key":"B36","doi-asserted-by":"publisher","first-page":"53","DOI":"10.1016\/j.applanim.2018.04.008","article-title":"Using qualitative behaviour assessment (QBA) to explore the emotional state of horses and its association with human-animal relationship","volume":"204","author":"Minero","year":"2018","journal-title":"Appl Anim Behav Sci."},{"key":"B37","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1079\/PAVSNNR201914028","article-title":"Facial expressions and emotions in domestic animals","volume":"14","author":"Lezama-Garc\u00eda","year":"2019","journal-title":"CAB Rev Perspect Agric Vet Sci Nutr Nat Resour."},{"key":"B38","doi-asserted-by":"publisher","first-page":"3334","DOI":"10.3390\/ani11113334","article-title":"Current advances in assessment of dog's emotions, facial expressions, and their use for clinical recognition of pain","volume":"11","author":"Mota-Rojas","year":"2021","journal-title":"Animals."},{"key":"B39","doi-asserted-by":"publisher","first-page":"1976","DOI":"10.1097\/j.pain.0000000000001939","article-title":"The revised international association for the study of pain definition of pain: concepts, challenges, and compromises","volume":"161","author":"Raja","year":"2020","journal-title":"Pain."},{"key":"B40","doi-asserted-by":"publisher","first-page":"55","DOI":"10.1016\/j.tvjl.2018.05.004","article-title":"The neurobiology of acute pain","volume":"237","author":"Bell","year":"2018","journal-title":"Vet J"},{"key":"B41","doi-asserted-by":"publisher","first-page":"703","DOI":"10.1016\/S0195-5616(08)70003-2","article-title":"Physiology of pain","volume":"30","author":"Lamont","year":"2000","journal-title":"Vet Clin North Am Small Anim Pract."},{"key":"B42","doi-asserted-by":"publisher","first-page":"63","DOI":"10.1152\/physiol.00022.2017","article-title":"Comparative physiology of nociception and pain","volume":"33","author":"Sneddon","year":"2018","journal-title":"Physiology."},{"key":"B43","doi-asserted-by":"publisher","first-page":"397","DOI":"10.1016\/j.cnc.2017.08.001","article-title":"Physiology of pain","volume":"29","author":"Ellison","year":"2017","journal-title":"Crit Care Nurs Clin North Am."},{"key":"B44","first-page":"p. 25","author":"Rosenberg","year":"2020","journal-title":"What the Face Reveals: Basic and Applied Studies of Spontaneous Expression Using the Facial Action Coding System (FACS)"},{"key":"B45","doi-asserted-by":"publisher","first-page":"201","DOI":"10.1016\/j.anbehav.2014.09.007","article-title":"Defining and assessing animal pain","volume":"97","author":"Sneddon","year":"2014","journal-title":"Anim Behav."},{"key":"B46","doi-asserted-by":"publisher","first-page":"43","DOI":"10.3389\/fnins.2014.00043","article-title":"The amygdalo-motor pathways and the control of facial expressions","volume":"8","author":"Gothard","year":"2014","journal-title":"Front Neurosci."},{"key":"B47","doi-asserted-by":"publisher","first-page":"134","DOI":"10.1002\/cne.21165","article-title":"Amygdala Interconnections with the cingulate motor cortex in the rhesus monkey","volume":"500","author":"Morecraft","year":"2007","journal-title":"J Comp Neurol."},{"key":"B48","doi-asserted-by":"publisher","first-page":"1016720","DOI":"10.3389\/fvets.2022.1016720","article-title":"The neurobiology of pain and facial movements in rodents: clinical applications and current research","volume":"9","author":"Dom\u00ednguez-Oliva","year":"2022","journal-title":"Front Vet Sci."},{"key":"B49","doi-asserted-by":"publisher","first-page":"89","DOI":"10.1126\/science.aaz9468","article-title":"Facial expressions of emotion states and their neuronal correlates in mice","volume":"368","author":"Dolensek","year":"2020","journal-title":"Science."},{"key":"B50","doi-asserted-by":"publisher","first-page":"480","DOI":"10.1016\/j.neubiorev.2020.07.013","article-title":"The development and use of facial grimace scales for pain measurement in animals","volume":"116","author":"Mogil","year":"2020","journal-title":"Neurosci Biobehav Rev."},{"key":"B51","doi-asserted-by":"publisher","first-page":"104371","DOI":"10.1016\/j.beproc.2021.104371","article-title":"Identifying facial expressions in dogs: a replication and extension study","volume":"186","author":"Bloom","year":"2021","journal-title":"Behav Processes."},{"key":"B52","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.beproc.2013.02.010","article-title":"Classifying dogs' (Canis familiaris) facial expressions from photographs","volume":"96","author":"Bloom","year":"2013","journal-title":"Behav Processes."},{"key":"B53","volume-title":"Veterinary Pain Management","author":"Gaynor","year":"2008"},{"key":"B54","doi-asserted-by":"publisher","first-page":"103","DOI":"10.1111\/vaa.12212","article-title":"An equine pain face","volume":"42","author":"Gleerup","year":"2015","journal-title":"Vet Anaesth Analg."},{"key":"B55","doi-asserted-by":"publisher","first-page":"615","DOI":"10.1111\/jsap.12283","article-title":"Evaluation of facial expression in acute pain in cats","volume":"55","author":"Holden","year":"2014","journal-title":"J Small Anim Pr."},{"key":"B56","doi-asserted-by":"publisher","first-page":"5262","DOI":"10.1038\/s41598-021-84696-7","article-title":"Agreement and reliability of the feline grimace scale among cat owners, veterinarians, veterinary students and nurses","volume":"11","author":"Evangelista","year":"2021","journal-title":"Sci Rep."},{"key":"B57","first-page":"231","article-title":"Identifying pain behaviors in dairy cattle functions and effects of pain","volume":"29","author":"Gleerup","year":"2017"},{"key":"B58","doi-asserted-by":"publisher","first-page":"e0251435","DOI":"10.1371\/journal.pone.0251435","article-title":"Measurement properties of pain scoring instruments in farm animals: a systematic review protocol using the COSMIN checklist","volume":"16","author":"Tomacheuski","year":"2021","journal-title":"PLoS ONE."},{"key":"B59","doi-asserted-by":"publisher","first-page":"66","DOI":"10.1016\/j.applanim.2017.01.005","article-title":"Development and application of CatFACS: are human cat adopters influenced by cat facial expressions?","volume":"189","author":"Caeiro","year":"2017","journal-title":"Appl Anim Behav Sci."},{"key":"B60","doi-asserted-by":"publisher","first-page":"e697","DOI":"10.1097\/j.pain.0000000000002474","article-title":"Measurement properties of grimace scales for pain assessment in nonhuman mammals: a systematic review","volume":"163","author":"Evangelista","year":"2022","journal-title":"Pain."},{"key":"B61","doi-asserted-by":"publisher","first-page":"2739","DOI":"10.1111\/jvim.17174","article-title":"Parasympathetic tone activity, heart rate, and grimace scale in conscious horses of 3 breeds before, during, and after nociceptive mechanical stimulation","volume":"38","author":"Flores","year":"2024","journal-title":"J Vet Intern Med."},{"key":"B62","doi-asserted-by":"publisher","first-page":"e82","DOI":"10.1002\/vetr.82","article-title":"Towards an improved pain assessment in castrated horses using facial expressions (HGS) and circulating miRNAs","volume":"188","author":"Dalla Costa","year":"2021","journal-title":"Vet Rec."},{"key":"B63","doi-asserted-by":"publisher","first-page":"104970","DOI":"10.1016\/j.applanim.2020.104970","article-title":"Use of the horse grimace scale to identify and quantify pain due to dental disorders in horses","volume":"225","author":"Marcantonio Coneglian","year":"2020","journal-title":"Appl Anim Behav Sci."},{"key":"B64","doi-asserted-by":"publisher","first-page":"781","DOI":"10.3390\/ani10050781","article-title":"Does thirty-minute standardised training improve the inter-observer reliability of the horse grimace scale (HGS)? A case study","volume":"10","author":"Dai","year":"2020","journal-title":"Animals."},{"key":"B65","doi-asserted-by":"publisher","first-page":"129","DOI":"10.1038\/s41598-023-50383-y","article-title":"Changes in the equine facial repertoire during different orthopedic pain intensities","volume":"14","author":"Ask","year":"2024","journal-title":"Sci Rep."},{"key":"B66","doi-asserted-by":"publisher","first-page":"1623","DOI":"10.3390\/ani13101623","article-title":"Horse grimace scale does not detect pain in horses with equine gastric ulcer syndrome","volume":"13","author":"Ferlini Agne","year":"2023","journal-title":"Anim an open access J from MDPI"},{"key":"B67","doi-asserted-by":"publisher","first-page":"106054","DOI":"10.1016\/j.applanim.2023.106054","article-title":"Work it out: investigating the effect of workload on discomfort and stress physiology of riding school horses","volume":"267","author":"Ijichi","year":"2023","journal-title":"Appl Anim Behav Sci."},{"key":"B68","doi-asserted-by":"publisher","first-page":"104411","DOI":"10.1016\/j.jevs.2023.104411","article-title":"109 Use of the horse grimace scale to evaluate markers of stress in horses involved in equine assisted activities","volume":"124","author":"Paladino","year":"2023","journal-title":"J Equine Vet Sci."},{"key":"B69","doi-asserted-by":"publisher","first-page":"105203","DOI":"10.1016\/j.jevs.2024.105203","article-title":"Welfare assessment of stabled horses in five equestrian disciplines","volume":"143","author":"Jovanovi\u0107","year":"2024","journal-title":"J Equine Vet Sci."},{"key":"B70","doi-asserted-by":"publisher","first-page":"175","DOI":"10.1016\/j.tvjl.2016.08.004","article-title":"Monitoring acute equine visceral pain with the equine utrecht university scale for composite pain assessment (EQUUS-COMPASS) and the equine utrecht university scale for facial assessment of pain (EQUUS-FAP): a validation study","volume":"216","author":"VanDierendonck","year":"2016","journal-title":"Vet J."},{"key":"B71","doi-asserted-by":"publisher","first-page":"85","DOI":"10.1016\/j.tvjl.2019.02.001","article-title":"Pain assessment in horses after orthopaedic surgery and with orthopaedic trauma","volume":"246","author":"van Loon","year":"2019","journal-title":"Vet J."},{"key":"B72","doi-asserted-by":"publisher","first-page":"105418","DOI":"10.1016\/j.rvsc.2024.105418","article-title":"Anatomical and functional basis of facial expressions and their relationship with emotions in horses","volume":"180","author":"Zimmermann","year":"2024","journal-title":"Res Vet Sci."},{"key":"B73","doi-asserted-by":"publisher","first-page":"1411","DOI":"10.3390\/ani10081411","article-title":"Development of a donkey grimace scale to recognize pain in donkeys (Equus asinus) post castration","volume":"10","author":"Orth","year":"2020","journal-title":"Animals."},{"key":"B74","doi-asserted-by":"publisher","first-page":"51","DOI":"10.3389\/fvets.2017.00051","article-title":"Development of a piglet grimace scale to evaluate piglet pain using facial expressions following castration and tail docking: a pilot study","volume":"4","author":"Viscardi A","year":"2017","journal-title":"Front Vet Sci."},{"key":"B75","doi-asserted-by":"publisher","first-page":"100","DOI":"10.3389\/fvets.2016.00100","article-title":"The assessment of facial expressions in piglets undergoing tail docking and castration: toward the development of the piglet grimace scale","volume":"3","author":"Di Giminiani","year":"2016","journal-title":"Front Vet Sci."},{"key":"B76","doi-asserted-by":"publisher","first-page":"108","DOI":"10.3389\/fvets.2016.00108","article-title":"A review of pain assessment in pigs","volume":"3","author":"Ison","year":"2016","journal-title":"Front Vet Sci"},{"key":"B77","doi-asserted-by":"publisher","first-page":"105720","DOI":"10.1016\/j.applanim.2022.105720","article-title":"Evaluating the utility of a CO2 surgical laser for piglet tail docking to reduce behavioral and physiological indicators of pain and to improve wound healing: a pilot study","volume":"254","author":"Lou","year":"2022","journal-title":"Appl Anim Behav Sci."},{"key":"B78","doi-asserted-by":"publisher","first-page":"2113","DOI":"10.3390\/ani10112113","article-title":"Development of a facial expression scale using farrowing as a model of pain in sows","volume":"10","author":"Navarro","year":"2020","journal-title":"Animals."},{"key":"B79","doi-asserted-by":"publisher","first-page":"108346","DOI":"10.1016\/j.compag.2023.108346","article-title":"ASPP-YOLOv5: a study on constructing pig facial expression recognition for heat stress","volume":"214","author":"Nie","year":"2023","journal-title":"Comput Electron Agric."},{"key":"B80","doi-asserted-by":"publisher","first-page":"e0175839","DOI":"10.1371\/journal.pone.0175839","article-title":"The sheep grimace scale as an indicator of post-operative distress and pain in laboratory sheep","volume":"12","author":"H\u00e4ger","year":"2017","journal-title":"PLoS ONE."},{"key":"B81","doi-asserted-by":"publisher","first-page":"70","DOI":"10.25271\/sjuoz.2024.12.1.1185","article-title":"Using sheep facial grimace scale, infrared thermography and cortisol hormone to measure pain in sheep infected with mastitis disease","volume":"12","author":"Hussein","year":"2024","journal-title":"Sci J Univ Zakho."},{"key":"B82","doi-asserted-by":"publisher","first-page":"27","DOI":"10.1159\/000526058","article-title":"Postoperative severity assessment in sheep","volume":"64","author":"Zentrich","year":"2023","journal-title":"Eur Surg Res."},{"key":"B83","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1007\/978-3-319-95369-4_9","article-title":"\u201cEstimation of Pain in Sheep Using Computer Vision","volume-title":"Handbook of Pain and Palliative Care","author":"Mahmoud","year":"2018"},{"key":"B84","doi-asserted-by":"publisher","first-page":"394","DOI":"10.1109\/FG.2017.56","article-title":"Estimating sheep pain level using facial action unit detection","volume":"2017","author":"Yiting","year":"2017","journal-title":"IEEE Conf Proc."},{"key":"B85","doi-asserted-by":"publisher","first-page":"49","DOI":"10.1016\/j.beproc.2016.09.010","article-title":"Coding and quantification of a facial expression for pain in lambs","volume":"132","author":"Guesgen","year":"2016","journal-title":"Behav Processes."},{"key":"B86","doi-asserted-by":"publisher","first-page":"106163","DOI":"10.1016\/j.applanim.2024.106163","article-title":"Ranking bovine pain-related behaviors using a logistic regression algorithm","volume":"271","author":"Trindade","year":"2024","journal-title":"Appl Anim Behav Sci."},{"key":"B87","doi-asserted-by":"publisher","first-page":"105258","DOI":"10.1016\/j.applanim.2021.105258","article-title":"Pain assessment based on facial expression of bulls during castration","volume":"236","author":"Yamada","year":"2021","journal-title":"Appl Anim Behav Sci."},{"key":"B88","doi-asserted-by":"publisher","first-page":"60","DOI":"10.1016\/j.jveb.2019.07.007","article-title":"Facial expression of pain in nellore and crossbred beef cattle","volume":"34","author":"M\u00fcller","year":"2019","journal-title":"J Vet Behav."},{"key":"B89","doi-asserted-by":"publisher","first-page":"3143","DOI":"10.3390\/ani12223143","article-title":"Limited effects of pain control treatments on behaviour and weight gain of pure and crossbred nellore heifer calves when subjected to hot-iron branding","volume":"12","author":"Hernandez","year":"2022","journal-title":"Animals."},{"key":"B90","doi-asserted-by":"publisher","first-page":"105951","DOI":"10.1016\/j.applanim.2023.105951","article-title":"A six-step process to explore facial expressions performances to detect pain in dairy cows with lipopolysaccharide-induced clinical mastitis","volume":"264","author":"Ginger","year":"2023","journal-title":"Appl Anim Behav Sci."},{"key":"B91","doi-asserted-by":"publisher","first-page":"226","DOI":"10.1016\/j.applanim.2011.10.018","article-title":"Addressing the pain associated with disbudding and dehorning in cattle","volume":"135","author":"Stafford","year":"2011","journal-title":"Appl Anim Behav Sci."},{"key":"B92","doi-asserted-by":"publisher","first-page":"3602","DOI":"10.3168\/jds.2010-3114","article-title":"Noninvasive assessment of autonomic activity for evaluation of pain in calves, using surgical castration as a model","volume":"93","author":"Stewart","year":"2010","journal-title":"J Dairy Sci."},{"key":"B93","doi-asserted-by":"publisher","first-page":"3287","DOI":"10.3168\/jds.S0022-0302(02)74417-2","article-title":"Responses to tail docking in calves and heifers","volume":"85","author":"Schreiner","year":"2002","journal-title":"J Dairy Sci."},{"key":"B94","doi-asserted-by":"publisher","first-page":"25620","DOI":"10.1038\/s41598-024-77147-6","article-title":"Development of the calf grimace scale for pain and stress assessment in castrated angus beef calves","volume":"14","author":"Farghal","year":"2024","journal-title":"Sci Rep."},{"key":"B95","doi-asserted-by":"publisher","first-page":"1223","DOI":"10.3390\/ani13071223","article-title":"The importance of animal models in biomedical research: current insights and applications","volume":"13","author":"Dom\u00ednguez-Oliva","year":"2023","journal-title":"Animals."},{"key":"B96","doi-asserted-by":"publisher","first-page":"673","DOI":"10.3390\/ani11030673","article-title":"Methods used and application of the mouse grimace scale in biomedical research 10 years on: a scoping review","volume":"11","author":"Whittaker","year":"2021","journal-title":"Animals."},{"key":"B97","first-page":"42","article-title":"Using the mouse grimace scale to reevaluate the efficacy of postoperative analgesics in laboratory mice","volume":"51","author":"Matsumiya","year":"2012","journal-title":"J Am Assoc Lab Anim Sci."},{"key":"B98","doi-asserted-by":"publisher","first-page":"359","DOI":"10.1038\/s41598-018-36897-w","article-title":"Evaluating analgesic efficacy and administration route following craniotomy in mice using the grimace scale","volume":"9","author":"Cho","year":"2019","journal-title":"Sci Rep."},{"key":"B99","doi-asserted-by":"publisher","first-page":"e35656","DOI":"10.1371\/journal.pone.0035656","article-title":"The assessment of post-vasectomy pain in mice using behaviour and the mouse grimace scale","volume":"7","author":"Leach","year":"2012","journal-title":"PLoS ONE."},{"key":"B100","doi-asserted-by":"publisher","first-page":"e0136000","DOI":"10.1371\/journal.pone.0136000","article-title":"The mouse grimace scale: a clinically useful tool?","volume":"10","author":"Miller","year":"2015","journal-title":"PLoS ONE."},{"key":"B101","doi-asserted-by":"publisher","first-page":"1648","DOI":"10.3390\/ani10091648","article-title":"Reliability of the mouse grimace scale in C57BL\/6JRj mice","volume":"10","author":"Hohlbaum","year":"2020","journal-title":"Animals."},{"key":"B102","doi-asserted-by":"publisher","first-page":"117","DOI":"10.1177\/0023677214559084","article-title":"Using the mouse grimace scale to assess pain associated with routine ear notching and the effect of analgesia in laboratory mice","volume":"49","author":"Miller","year":"2015","journal-title":"Lab Anim."},{"key":"B103","doi-asserted-by":"publisher","first-page":"100312","DOI":"10.1016\/j.mlwa.2022.100312","article-title":"Face detection and grimace scale prediction of white furred mice","volume":"8","author":"Vidal","year":"2022","journal-title":"Mach Learn with Appl."},{"key":"B104","doi-asserted-by":"publisher","first-page":"83","DOI":"10.1177\/0023677219881655","article-title":"Improvement of the mouse grimace scale set-up for implementing a semi-automated mouse grimace scale scoring (part 1)","volume":"54","author":"Ernst","year":"2020","journal-title":"Lab Anim."},{"key":"B105","doi-asserted-by":"publisher","first-page":"e0228059","DOI":"10.1371\/journal.pone.0228059","article-title":"Towards a fully automated surveillance of well-being status in laboratory mice using deep learning: starting with facial expression analysis","volume":"15","author":"Andresen","year":"2020","journal-title":"PLoS ONE."},{"key":"B106","doi-asserted-by":"publisher","first-page":"13894","DOI":"10.1038\/s41598-018-32297-2","article-title":"Grading facial expression is a sensitive means to detect grimace differences in orofacial pain in a rat model","volume":"8","author":"Sperry","year":"2018","journal-title":"Sci Rep."},{"key":"B107","doi-asserted-by":"publisher","first-page":"e97882","DOI":"10.1371\/journal.pone.0097882","article-title":"Psychometric assessment of the rat grimace scale and development of an analgesic intervention score","volume":"9","author":"Oliver","year":"2014","journal-title":"PLoS ONE."},{"key":"B108","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1038\/srep31667","article-title":"Real-time application of the rat grimace scale as a welfare refinement in laboratory rats","volume":"6","author":"Leung","year":"2016","journal-title":"Sci Rep."},{"key":"B109","first-page":"34","article-title":"Use of the rat grimace scale to evauate neuropathic pain in a model of cervical radiculopathy","volume":"67","author":"Philips","year":"2017","journal-title":"Comp Med."},{"key":"B110","doi-asserted-by":"publisher","first-page":"13","DOI":"10.1016\/j.ynpai.2017.10.001","article-title":"The grimace scale reliably assesses chronic pain in a rodent model of trigeminal neuropathic pain","volume":"2","author":"Akintola","year":"2017","journal-title":"Neurobiol Pain."},{"key":"B111","doi-asserted-by":"publisher","first-page":"e0209467","DOI":"10.1371\/journal.pone.0209467","article-title":"Comparing the rat grimace scale and a composite behaviour score in rats","volume":"14","author":"Klune","year":"2019","journal-title":"PLoS ONE."},{"key":"B112","doi-asserted-by":"publisher","first-page":"18859","DOI":"10.1038\/s41598-023-46123-x","article-title":"An automated rat grimace scale for the assessment of pain","volume":"13","author":"Arnold","year":"2023","journal-title":"Sci Rep."},{"key":"B113","doi-asserted-by":"publisher","first-page":"3161","DOI":"10.3390\/ani13203161","article-title":"Rat grimace scale as a method to evaluate animal welfare, nociception, and quality of the euthanasia method of wistar rats","volume":"13","author":"Dom\u00ednguez-Oliva","year":"2023","journal-title":"Animals."},{"key":"B114","doi-asserted-by":"publisher","first-page":"e0166652","DOI":"10.1371\/journal.pone.0166652","article-title":"The influence of isoflurane anaesthesia on the rat grimace scale","volume":"11","author":"Miller","year":"2016","journal-title":"PLoS ONE."},{"key":"B115","doi-asserted-by":"publisher","first-page":"782486","DOI":"10.3389\/fvets.2022.782486","article-title":"Evaluating pain and analgesia effectiveness following routine castration in rabbits using behavior and facial expressions","volume":"9","author":"Miller","year":"2022","journal-title":"Front Vet Sci"},{"key":"B116","doi-asserted-by":"publisher","first-page":"e0221377","DOI":"10.1371\/journal.pone.0221377","article-title":"Reliability and construct validity of a composite pain scale for rabbit (CANCRS) in a clinical environment","volume":"15","author":"Banchi","year":"2020","journal-title":"PLoS ONE."},{"key":"B117","doi-asserted-by":"publisher","first-page":"282","DOI":"10.12968\/vetn.2020.11.6.282","article-title":"Assessing pain in rabbits: how well does the rabbit grimace scale work in the veterinary practice?","volume":"11","author":"Shaw","year":"2020","journal-title":"Vet Nurse."},{"key":"B118","doi-asserted-by":"publisher","first-page":"e0187986","DOI":"10.1371\/journal.pone.0187986","article-title":"The composition and initial evaluation of a grimace scale in ferrets after surgical implantation of a telemetry probe","volume":"12","author":"Reijgwart","year":"2017","journal-title":"PLoS ONE."},{"key":"B119","doi-asserted-by":"publisher","first-page":"2","DOI":"10.1093\/emph\/eoy035","article-title":"Tinbergen's four questions: two proximate, two evolutionary","volume":"2019","author":"Nesse","year":"2018","journal-title":"Evol Med Public Heal."},{"key":"B120","doi-asserted-by":"publisher","first-page":"445","DOI":"10.1177\/1098612X18771206","article-title":"Recognising and assessing feline emotions during the consultation History, body language and behaviour","volume":"20","author":"Ellis","year":"2018","journal-title":"J Feline Med Surg."},{"key":"B121","doi-asserted-by":"publisher","first-page":"e8967","DOI":"10.7717\/peerj.8967","article-title":"Clinical applicability of the feline grimace scale: real-time versus image scoring and the influence of sedation and surgery","volume":"8","author":"Evangelista","year":"2020","journal-title":"PeerJ."},{"key":"B122","doi-asserted-by":"publisher","first-page":"1098612X231211765","DOI":"10.1177\/1098612X231211765","article-title":"Construct validity, responsiveness and reliability of the feline grimace scale in kittens","volume":"25","author":"Cheng","year":"2023","journal-title":"J Feline Med Surg"},{"key":"B123","doi-asserted-by":"publisher","first-page":"2914","DOI":"10.3390\/ani12212914","article-title":"The effects of sedation with dexmedetomidine\u2013butorphanol and anesthesia with propofol\u2013isoflurane on feline grimace scale\u00a9 scores","volume":"12","author":"Watanabe","year":"2022","journal-title":"Animals."},{"key":"B124","doi-asserted-by":"publisher","first-page":"1098612X221145499","DOI":"10.1177\/1098612X221145499","article-title":"Can cat caregivers reliably assess acute pain in cats using the feline grimace scale? A large bilingual global survey","volume":"25","author":"Monteiro","year":"2023","journal-title":"J Feline Med Surg"},{"key":"B125","doi-asserted-by":"publisher","first-page":"e11225","DOI":"10.7717\/peerj.11225","article-title":"Clinical validation of the short and long UNESP-Botucatu scales for feline pain assessment","volume":"9","author":"Belli","year":"2021","journal-title":"PeerJ."},{"key":"B126","doi-asserted-by":"publisher","first-page":"e13134","DOI":"10.7717\/peerj.13134","article-title":"Multilingual validation of the short form of the Unesp-Botucatu Feline Pain Scale (UFEPS-SF)","volume":"10","author":"Luna","year":"2022","journal-title":"PeerJ."},{"key":"B127","doi-asserted-by":"publisher","first-page":"167","DOI":"10.1163\/156853964X00012","article-title":"Facial expression in primates with remarks on a parallel development in certain carnivores","volume":"22","author":"Bolwing","year":"1964","journal-title":"Behav."},{"key":"B128","doi-asserted-by":"publisher","first-page":"1011","DOI":"10.2460\/javma.256.9.1011","article-title":"Comparison of liposomal bupivacaine and 0","volume":"256","author":"Reader","year":"2020","journal-title":"J Am Vet Med Assoc."},{"key":"B129","first-page":"294","article-title":"Prevalence and management of pain in dogs in the emergency service of a veterinary teaching hospital","volume":"61","author":"Rousseau-Blass","year":"2020","journal-title":"Can Vet J"},{"key":"B130","doi-asserted-by":"publisher","first-page":"8","DOI":"10.1111\/eve.4_13534","article-title":"Comparison of the horse grimace scale (hgs), the composite pain scale (cps) and the equine utrecht university scale for composite pain assessment (EQUUS-COMPASS SCALE) for assessment of colic patients","volume":"33","author":"Rosenzweig","year":"2021","journal-title":"Equine Vet Educ."},{"key":"B131","doi-asserted-by":"publisher","first-page":"e4800","DOI":"10.1002\/vetr.4800","article-title":"Application of the horse grimace scale in horses with dental disease: preliminary findings","volume":"9","author":"Sidwell","year":"2024","journal-title":"Vet Rec."},{"key":"B132","doi-asserted-by":"publisher","first-page":"112","DOI":"10.1016\/j.jevs.2019.02.005","article-title":"Interobserver reliability of the animal welfare indicators welfare assessment protocol for horses","volume":"75","author":"Czycholl","year":"2019","journal-title":"J Equine Vet Sci."},{"key":"B133","doi-asserted-by":"publisher","first-page":"302","DOI":"10.3389\/fvets.2020.00302","article-title":"Inter-rater reliability of the feline grimace scale in cats undergoing dental extractions","volume":"7","author":"Watanabe","year":"2020","journal-title":"Front Vet Sci."},{"key":"B134","doi-asserted-by":"publisher","first-page":"1098612X231194423","DOI":"10.1177\/1098612X231194423","article-title":"Inter-observer reliability of three feline pain scales used in clinical practice","volume":"25","author":"Adami","year":"2023","journal-title":"J Feline Med Surg."},{"key":"B135","first-page":"201","article-title":"\u201cRecognition and assessment of pain in cats.\u201d","author":"Monteiro","year":"2015"},{"key":"B136","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1079\/PAVSNNR201914013","article-title":"Meconium aspiration syndrome in mammals","volume":"14","author":"Mart\u00ednez-Burnes","year":"2019","journal-title":"CAB Rev."},{"key":"B137","doi-asserted-by":"publisher","first-page":"e2023ss01","DOI":"10.31893\/jabb.23ss01","article-title":"Neurobiology of emotions in animal relationships: facial expressions and their biological functions in mammals","volume":"11","author":"Mota-Rojas","year":"2023","journal-title":"J Anim Behav Biometeorol."},{"key":"B138","doi-asserted-by":"publisher","first-page":"106223","DOI":"10.1016\/j.tvjl.2024.106223","article-title":"Enhancing the horse grimace scale (HGS): proposed updates and anatomical descriptors for pain assessment","volume":"307","author":"Werner","year":"2024","journal-title":"Vet J."},{"key":"B139","doi-asserted-by":"publisher","first-page":"28","DOI":"10.1016\/j.applanim.2007.05.010","article-title":"Visual acuity of pigs at different light intensities","volume":"111","author":"Zonderland","year":"2008","journal-title":"Appl Anim Behav Sci."},{"key":"B140","doi-asserted-by":"publisher","first-page":"847","DOI":"10.3390\/agriculture11090847","article-title":"Towards facial expression recognition for on-farm welfare assessment in pigs","volume":"11","author":"Hansen","year":"2021","journal-title":"Agriculture."},{"key":"B141","doi-asserted-by":"publisher","first-page":"1944","DOI":"10.3390\/ani12151944","article-title":"The application of 3d landmark-based geometric morphometrics towards refinement of the piglet grimace scale","volume":"12","author":"Lou","year":"2022","journal-title":"Animals."},{"key":"B142","doi-asserted-by":"publisher","first-page":"178","DOI":"10.30802\/AALAS-JAALAS-18-000044","article-title":"Influence of rater training on inter- and intrarater reliability when using the rat grimace scale","volume":"58","author":"Zhang","year":"2019","journal-title":"J Am Assoc Lab Anim Sci."},{"key":"B143","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1177\/1098612X241275284","article-title":"Effects of training on feline grimace scale scoring for acute pain assessment in cats","volume":"26","author":"Robinson","year":"2024","journal-title":"J Feline Med Surg"}],"container-title":["Frontiers in Veterinary Science"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fvets.2025.1546719\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,3,4]],"date-time":"2025-03-04T07:09:23Z","timestamp":1741072163000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fvets.2025.1546719\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,3,4]]},"references-count":143,"alternative-id":["10.3389\/fvets.2025.1546719"],"URL":"https:\/\/doi.org\/10.3389\/fvets.2025.1546719","relation":{},"ISSN":["2297-1769"],"issn-type":[{"value":"2297-1769","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,3,4]]},"article-number":"1546719"}}