Search

This study aimed to compare the analgesic and cardiopulmonary effects of levobupivacaine with or without dexmedetomidine, in cats undergoing ovariohysterectomy. In this prospective, randomized, and blinded clinical trial, 24 healthy cats were recruited. Animals received either saline (S group; 2 mL NaCl), levobupivacaine alone (Lev; 0.35 mg/kg), or levobupivacaine with dexmedetomidine (LevDex group; 0.004 mg/kg), which was infiltrated intraoperatively into the subcutaneous tissue at various incision sites, including the right and left ovarian pedicles and the caudal aspect of the uterine body. Intraoperative analgesia was evaluated using a cumulative pain scale, while postoperative analgesia was assessed at various time points: before surgery (T b ), and at 0 (T 0 ), 1 (T 1h ), 2 (T 2h ), 4 (T 4h ), 8 (T 8h ), 12 (T 12h ), and 24 (T 24h ) hours after the procedure, using the UNESP-Botucatu multidimensional composite pain scale (MCPS). Significant decreases in heart rate, respiratory rate, and mean arterial pressure were observed in LevDex group as compared to S and Lev groups (p < 0.05). The S group required significantly more rescue morphine doses than the LevDex group (p = 0.029), but the difference was not significant when compared to the Lev group (p = 0.123). At T 1h and T 2h , the S group had significantly higher MCPS scores than both the Lev and LevDex groups (p = 0.029). However, at T 8h , no significant difference was found between the S and LevDex groups (p = 0.741). While adding dexmedetomidine to levobupivacaine may slightly prolong postoperative analgesia, this combination does not provide significant additional benefit over levobupivacaine alone in terms of response to surgical stimulation., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Pain management in amphibians is an emerging field of veterinary medicine with only a limited number of analgesics studied for their efficacy. The African-clawed frog, Xenopus laevis, is a popular animal model in research due to its oocyte morphology and embryonic development. We investigated analgesic effects of 2 formulations of meloxicam (standard and extended release [ER]) along with their pharmacokinetics and potential toxicity in this species. Adult female African-clawed frogs (n = 6/group) received either standard (0.2, 0.4, 1, or 5 mg/kg) or ER meloxicam (0.6, 1.2, 3, or 15 mg/kg) injected into the dorsal lymph sac. The acetic acid test (AAT) was performed at -1, 1, 6, 12, 24, 48, and 72 h postadministration to evaluate pain response. In addition, a subset of frogs (n = 2/group) were euthanized 72 h postinjection and submitted for necropsy. There were no significant differences in AAT with both formulations compared with saline control. No signs of meloxicam-induced toxicity with either formulation was present in histology. A pharmacokinetic study was conducted for both the standard and ER formulation of meloxicam at 5 and 15 mg/kg, respectively. Results were consistent with the fact that both formulations of meloxicam were readily absorbed with the standard plasma concentrations peaking at 20.40 µg/mL at 2 h and ER plasma concentration at 30.4 µg/mL at 12 h. The elimination half-life was only determinable for standard formulation (7.74 h). According to the AAT, both formulations of meloxicam did not provide effective analgesia in adult female Xenopus laevis despite reaching high plasma concentrations.

Objectives: The aim of the study was to determine the effects of training on inter-rater reliability and agreement of Feline Grimace Scale (FGS) scoring by small animal practitioners., Methods: Seven small animal veterinarians were asked to score a total of 50 images of cats in varying degrees of pain before and after training in FGS scoring. Participant scores were compared with those of an expert rater. Inter-rater reliability was analyzed using the intraclass correlation coefficient (ICC) before and after training (ICC <0.50 = poor reliability, 0.50-0.75 = moderate reliability, 0.76-0.90 = good reliability and >0.90 = excellent reliability). The Bland-Altman method was used to analyze the limits of agreement (LoAs) and bias between participants and the expert rater., Results: After training, the ICC classification improved for each action unit (ear position, orbital tightening, muzzle tension, whiskers change and head position). The inter-rater reliability for the total FGS ratio scores before and after the FGS training session was moderate (ICC = 0.75; 95% confidence interval [CI] 0.66-0.83) and good (ICC = 0.80; 95% CI 0.73-0.87), respectively. Before training, LoAs were -0.277 to 0.310 with a bias of 0.016. After training, LoAs were -0.237 to 0.255 with a bias of 0.008. The bias was low (<0.1) both before and after training and LoAs did not span the FGS analgesic threshold (0.39)., Conclusions and Relevance: Training in FGS scoring improved inter-rater reliability and agreement among seven small animal veterinarians and the veterinarians' skills in pain assessment., Competing Interests: Conflict of interestThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objectives: The aim of the study was to assess cat guardians' concern levels and veterinary care decisions pertaining to behaviors that might signify pain before and after receiving brief pain-related educational information. The secondary aims were to evaluate cat guardians' perceptions of the usefulness of a modified version of the Colorado State University Feline Acute Pain Scale (CSU-FAPS) in identifying their cat's pain level, determining if they should take their cat to the veterinarian and describing their cat's pain to their veterinarian., Methods: Participants were recruited through Prolific. An electronic survey was created in Qualtrics and distributed via a link offered in Prolific., Results: A total of 362 surveys were completed by participants who resided in the USA and were the primary caretaker of at least one cat. Significant differences between participants' concern levels before and after pain-related educational information were found for two of the three scenarios. Significant differences were found between participants' veterinary-related behavior choices before and after pain-related educational information for all three scenarios. The most common reasons for not seeking immediate veterinary care included elements related to cost and stress for guardian and cat during veterinary visits. The majority of participants reported finding the CSU-FAPS useful for identifying their cat's pain level (90%), determining if they should take their cat to the veterinarian (86%) and describing their cat's pain to their veterinarian (92%)., Conclusions and Relevance: Guardians' interpretations of and subsequent actions to behaviors that might suggest pain carry great implications for feline health and wellbeing. After exposure to brief pain-related educational material, guardians in our study reported significant increases in stated concern related to their cat's change in behavior and intention to seek veterinary care. These findings suggest that even very brief pain-related educational material can have a positive impact on cat guardians' perceptions of feline behavior changes and increase the possibility they obtain appropriate veterinary care., Competing Interests: Conflict of interestThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

The use of grimace scales enables the clinical identification of changes in the facial expressions of animals caused by pain. The Horse Grimace Scale (HGS) is one such tool, comprising a pain coding system based on facial expressions and assessing six Facial Action Units (FAUs). Each FAU is accompanied by descriptions and anatomical details to assist the evaluator. However, the morphological descriptions for certain FAUs in the HGS are not sufficiently detailed, potentially hindering accurate interpretation. This study is an analytical investigation aimed at enhancing the morphoanatomical details in the HGS and providing raters with more comprehensive materials for pain evaluation in horses using this scale. To achieve this, detailed anatomical analyses were conducted using established references in veterinary anatomy. Initially, we propose substituting the term 'ear' with 'auricle' or 'pinna' and replacing 'area above the eye' with 'supraorbital region' for anatomical accuracy. Additionally, we introduce detailed morphoanatomical descriptions that identify specific landmarks, with the goal of ensuring more consistent application of the HGS and reducing interpretation variability. Furthermore, this study provides an explanation of the muscles involved in the investigated FAUs. These adjustments on the descriptions and evaluations remain unverified, however it is anticipated that the descriptive enhancements lead us to understand that higher interobserver reliability can be achieved for each of the FAUs., Competing Interests: Conflict of Interest The authors declare that this study was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest., (Copyright © 2024. Published by Elsevier Ltd.)

Background: Parasympathetic tone activity (PTA) in response to nociceptive stimulus in conscious non-sedated horses is unknown., Objectives: Study PTA, heart rate (HR), and horse grimace scale (HGS) at rest and during mechanical nociceptive stimulation., Animals: Ninety healthy young adult horses (females, males): 30 each of Friesians, Quarter Horses, and Warmbloods., Methods: Prospective control study. The study consisted of habituation to equipment (Day 1), baseline recordings (Days 2 and 3), and nociceptive testing applying mild pressure to the metacarpus (Day 4). Parasympathetic tone, HR, and HGS were recorded simultaneously on Days 2 to 4. Each study lasted 30 minutes and was done in triplicate at 3 different time points per day., Results: Baseline PTA was not different among breeds. It decreased in Warmbloods and Quarter Horses during placement of the stimulus device without stimulation (P < .01). A significant decrease in PTA (P < .001) occurred during nociceptive stimulus (marked in Quarter Horses, intermediate in Warmbloods, and mild in Friesians). Heart rate and HGS increased significantly (P < .001) during the stimulus in all breeds but returned to baseline poststimulation. Friesians required higher pressure (P < .05) to elicit an aversive response to the stimulus., Conclusions: Horses' PTA, HR, and HGS change in response to a mild mechanical nociceptive stimulus with Friesians showing less variation. Stress induced a decrease in PTA in Quarter Horses and Warmbloods but not in Friesians. Friesians appeared to be more tolerant to pain based on PTA, HR, and HGS findings compared with other breeds., (© 2024 The Author(s). Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objective: To evaluate if students without training assess pain similarly to an expert, and to compare indications for analgesic intervention based on student opinions versus scale scoring., Study Design: Prospective, blind, randomized, cross-sectional study., Animals: Video recordings of a bull, horse, cat, pig and sheep., Methods: First-year veterinary medicine students assessed one video of a horse (n = 44) and one video of a bull (n = 39). Third-year veterinary medicine students assessed one video of a cat (n = 23) and one video of a pig (n = 21). Fourth-year animal science students (n = 16) assessed one video of a sheep. The species assessed by different student classes were determined randomly. Students were unaware of animal history or existing pain assessment and decided whether they would provide analgesia according to their opinion. They then scored each video using species-specific validated pain scales. Scores were compared with those of a board-certified anesthesiologist (expert). Chi-square test was used to compare students and expert., Results: Students underestimated the expert's score by 8-20%, except for the horse. There was no difference between the analgesic indication according to the assessment of the expert (143/143, 100%) and students (141/143, 98.6%) considering the defined analgesic intervention threshold for each scale (p = 0.478). The indication for analgesic intervention according to students' opinion (116/143, 81.1%) was lower than that according to their scale scores (141/143, 98.6%) (p < 0.0001)., Conclusions and Clinical Relevance: Students tended to underestimate pain; however, they detected pain that requires analgesic intervention in animals similarly to an expert. The use of scales optimized the indication for providing analgesia when animals were experiencing pain that required analgesic intervention., (Copyright © 2024 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Objective: To clinically evaluate previously developed pain scales [Donkey Chronic Pain Composite Pain Scale (DCP-CPS), Donkey Chronic Pain Facial Assessment of Pain (DCP-FAP) and combined Donkey Chronic Pain Scale (DCPS)], including behavioural and facial expression-based variables, for the assessment of chronic pain in donkeys., Study Design: Prospective, blinded clinical study., Animal: A group of 77 donkeys (34 patients and 43 healthy control animals)., Methods: Animals were assessed by two observers that were blinded to the condition of the animals., Results: Both DCP-CPS and DCP-FAP, and resulting combined DCPS scores, showed good interobserver reliability [intraclass correlation coefficient (ICC) = 0.91, 95% confidence interval (CI) = 0.86-0.95, p < 0.001; ICC = 0.71, CI = 0.50-0.83, p < 0.001 and ICC = 0.84, CI = 0.72-0.91, p < 0.001, respectively]. All scores (DCP-CPS, DCP-FAP and the resulting combined DCPS) were significantly higher for patients than for controls at all time points (p < 0.001 for all three scales). Sensitivity and specificity for identification of pain (cut-off value >3) was 73.0% and 65.1% for DCP-CPS, and 60.9% and 83.3% for DCP-FAP, respectively. For the combined DCPS, sensitivity was 87.0% and specificity 90.9% (cut-off value >6)., Conclusions and Clinical Relevance: Based on behavioural and facial expression-based variables, DCPS proved a promising and reproducible tool to assess different types of chronic pain in donkeys. The combination of behavioural and facial expression-based variables showed the best discriminatory characteristics in the current study. Further studies are needed for refinement of these tools., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Purpose: To evaluate the effect of post-surgical photobiomodulation therapy in dogs., Methods: Twenty dogs were selected for elective gastropexy and randomly divided into a control (CG, n = 10) and a PBMT group (PBMTG, n = 10). Pre‑medication consisted of medetomidine and butorphanol. Meloxicam was administered before the procedure. Induction was performed with propofol and maintained with sevoflurane. Local blocks with lidocaine were used. Incisional gastropexy was performed in all animals. PBMTG received PBMT immediately after surgery. The need for postoperative rescue analgesia, if the animal had eaten by the evaluation momen, and pain scores were collected using the Glasgow Composite Measure Pain Scale - Short Form (CMPS‑SF) at 1, 2, 4, 6, 8, 12, 16, 20, and 24 h post‑endotracheal extubation. CMPS‑SF scores were compared with the Mann-Whitney Test and proportions of animals that required rescue analgesia and had eaten with a χ 2 test. P was set at < 0.05., Results: No rescue analgesia was needed for any animal. Still, significant differences were observed in CMPS-SF scores between CG and PBMTG between 1 and 4 h post-extubation. PBMTG had a significantly higher proportion of animals eating up to the 8 h post-extubation evaluation moment., Conclusion: Adding post-surgical photobiomodulation to a standard anesthesia and analgesia protocol reduced CMPS-SF scores and increased the proportion of animals that resumed eating compared to the standard protocol alone., (© 2024. The Author(s).)

A prospective, quasi-experimental, clinical trial was performed to assess acute postoperative pain in healthy female dogs following elective ovariectomy by either laparoscopy (n=13) or laparotomy (n=14). Pain was assessed by both a veterinarian at the hospital, and by the owner once the patient was discharged. The Spanish version of the short form of the Glasgow Composite Measuring Pain Scale (CMPS-SF) was used. Pain scores were assessed by the veterinarian preoperatively and at 1, 2, 4, and 6 h after extubation, whilst owner-assessed scores were performed preoperatively and at postoperative days 0, 1, 2, 3, 5 and 7. Data were compared with Mann-Whitney-U test. Veterinarian-assessed CMPS-SF scores were different between both groups at all postoperative times but not at baseline, being below 6/24 in all dogs in the laparoscopy group, but equal to or greater than 6/24 in the laparotomy group at 1 h (n=12), and 4 h (n=4) (P<0.001 and P=0.029, respectively). There were also differences in pain scores between both groups at 2 h (P=0.012) and 6 h (P=0.007), being below 6/24 in all of them. However, there were no differences in owner assessments between groups. In conclusion, ovariectomy performed by laparoscopy induced lower pain scores that were below the pain threshold set by the CMPS-SF during the first 6 h postoperatively. After discharge, and up to one week later, ongoing owner-assessed scores suggest no pain was induced with neither of the techniques. Owners were proactive allowing real-time pain assessment to be reported. The development and validation of instruments for acute pain assessment by owners is warranted, as these tools are currently lacking., Competing Interests: Declaration of Competing Interest None of the authors has any financial or personal relationships that could inappropriately influence or bias the content of the paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Bovine pain assessment relies on validated behavioral scales related to normal and pain-related behaviors. This study investigated the reliability and applicability of real-time and video-recorded pain assessment, and their agreement, in young, adult bulls undergoing surgical castration. Ten Nelore and nine Angus bulls underwent general anesthesia and surgical castration. Three-minute real-time observations and simultaneous videos were recorded at - 48 h (M0), before sedation, under fasting (M1), after surgery, 3 h after sternal recumbency (M2), after rescue analgesia (M3) and at 24 h (M4). Animals received morphine (after M2), dipyrone (after M3), and flunixin meglumine after surgical castration (M4). Two trained evaluators assessed real-time (n = 95) and video-recorded time-points (n = 95) using the Unesp-Botucatu Cattle Pain Scale (UCAPS). Both assessment methods inferred 'very good' reliability (≥ 0.81) with minimal bias, however, video-recorded assessment (4.33 ± 2.84) demonstrated slightly higher scores compared to real-time (3.08 ± 2.84). The results from this study suggest that UCAPS can be used in real-time or video-recorded to assess pain and guide analgesic therapy in cattle., (© 2024. The Author(s).)

Background: Grapiprant is a novel anti-inflammatory drug approved for the treatment of pain associated with osteoarthritis in dogs., Objective: Compare the efficacy of grapiprant vs meloxicam for the management of postoperative joint pain in dogs., Animals: Forty-eight dogs presented with cranial cruciate ligament disease and treated by tibial plateau leveling osteotomy (TPLO) between May 2020 and May 2022., Methods: In this randomized, double blinded, prospective clinical trial, client-owned dogs with naturally occurring unilateral cruciate ligament rupture were enrolled on the day of surgery. The day after surgery, all animals received a subcutaneous injection of 0.2 mg/kg of meloxicam and were randomly assigned to receive either oral grapiprant (2 mg/kg) or meloxicam (0.1 mg/kg), once a day for 14 days, in a blinded manner. The primary endpoint of the study was the pain severity (PSS) and interference (PIS) scores, assessed by the Canine Brief Pain Inventory (CBPI) at day 3, 7, 10 and 15 after the surgery., Results: Three days after surgery, grapiprant treated dogs had lower PSS compared to meloxicam treated dogs with a mean ± SD of 2.76 ± 0.18 vs 3.25 ± 0.23, respectively (difference of -0.49 [95% CI -0.94 to -0.04], P = .032). Pain Interference Score was also lower in grapiprant group at day 3 (4.11 ± 0.18 vs 4.69 ± 0.16 in meloxicam group [difference of -0.58 {95% CI -1.03 to -0.13}, P = .013]) and at day 10 (2.23 ± 0.13 vs 2.72 ± 0.28 [difference of -0.49 {95% CI -0.92 to -0.01}, P = .049])., Conclusions and Clinical Importance: Our study supports the use of grapiprant as an alternative analgesic to meloxicam for management of postoperative joint pain in dogs., (© 2024 The Author(s). Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Objective: To describe the effect of two doses of maropitant on pain scores, food intake, and fecal output in domestic rabbits (Oryctolagus cuniculus) undergoing elective ovariohysterectomy or orchiectomy., Animals: 26 (11 female, 15 male) rabbits from three institutions., Procedures: Rabbits were randomly assigned to one of three treatment groups: low-dose maropitant (LDM; 2 mg/kg SC once; n=8), moderate-dose maropitant (MDM; 4 mg/kg SC once; n=10), and control (saline equivalent to 4 mg/kg maropitant SC once; n=8), administered prior to surgery. Following surgery, all rabbits were provided buprenorphine (0.06 mg/kg q 8 hours) and meloxicam (1 mg/kg q 24 hours) intramuscularly. Rabbits were monitored using video surveillance postoperatively until 24 hours after surgery or discharge from the hospital, whichever came first. Pain scores were assessed by three blinded observers, and results were grouped into early (0-4 hours), mid (5-8 hours), and late (12-24 hours) time frames. Food intake and fecal output were compared between groups. Statistical analysis was performed using Chi square, Fisher's exact tests, and a mixed model approach., Results: There were no adverse effects with maropitant administration. Rabbits that received MDM had significantly lower pain scores in the mid-time frame and behavior scores in the late-time frame compared to controls. Male rabbits consumed more food than females and rabbits hospitalized longer than 12 hours consumed more food than those that were discharged prior. No significant differences were detected in facial grimace scale scores, food intake, or fecal production among treatment groups., Conclusions and Clinical Relevance: Moderate dose maropitant decreased pain related behaviors in the mid-time frame and behavior scores in the late-time frame after surgery. Further studies are necessary to better characterize the potential use of maropitant in postoperative analgesia., Competing Interests: Declaration of competing interest The authors have no conflicts of interest., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Facial expressions have increasingly been used to assess emotional states in mammals. The recognition of pain in research animals is essential for their well-being and leads to more reliable research outcomes. Automating this process could contribute to early pain diagnosis and treatment. Artificial neural networks have become a popular option for image classification tasks in recent years due to the development of deep learning. In this study, we investigated the ability of a deep learning model to detect pain in Japanese macaques based on their facial expression. Thirty to 60 min of video footage from Japanese macaques undergoing laparotomy was used in the study. Macaques were recorded undisturbed in their cages before surgery (No Pain) and one day after the surgery before scheduled analgesia (Pain). Videos were processed for facial detection and image extraction with the algorithms RetinaFace (adding a bounding box around the face for image extraction) or Mask R-CNN (contouring the face for extraction). ResNet50 used 75% of the images to train systems; the other 25% were used for testing. Test accuracy varied from 48 to 54% after box extraction. The low accuracy of classification after box extraction was likely due to the incorporation of features that were not relevant for pain (for example, background, illumination, skin color, or objects in the enclosure). However, using contour extraction, preprocessing the images, and fine-tuning, the network resulted in 64% appropriate generalization. These results suggest that Mask R-CNN can be used for facial feature extractions and that the performance of the classifying model is relatively accurate for nonannotated single-frame images.

While rodents are used extensively for studying pain, there is a lack of reported direct comparisons of thermal and mechanical pain testing methods in rats of different genetic backgrounds. Understanding the range of interindividual variability of withdrawal thresholds and thermal latencies based on these testing methods and/or genetic background is important for appropriate experimental design. Testing was performed in two common rat genetic backgrounds: outbred Sprague-Dawley (SD) and inbred Fischer 344 (F344). Male and female, 10- to 14-wk-old F344 and SD rats were used to assess withdrawal thresholds in 3 different modalities: the Randall-Selitto test (RST), Hargreaves test (HT), and tail flick test (TFT). The RST was performed by using an operator-controlled handheld instrument to generate a noxious pressure stimulus to the left hind paw. The HT and the TFT used an electronically controlled light source to deliver a noxious thermal stimulus to the left hind paw or tail tip, respectively. Rats of each sex and genetic background underwent one type of test on day 0 and day 7. Withdrawal thresholds and thermal latencies were compared among tests. No significant differences were observed. Our findings can serve as a guide for researchers considering these nociceptive tests for their experiments.

Objectives: To evaluate analgesia, sedation and adverse effects of two doses of subcutaneous methadone in dogs undergoing tibial plateau levelling osteotomy., Materials and Methods: Seventeen client-owned dogs undergoing unilateral tibial plateau levelling osteotomy were randomly allocated to receive either 0.25 mg/kg methadone (eight dogs) or 0.5 mg/kg methadone (nine dogs). All dogs were premedicated with methadone and 2 to 6 mcg/kg dexmedetomidine subcutaneously. They were induced and maintained on a standard protocol. All animals received a second dose of methadone subcutaneously 4 hours after premedication and a 4.4 mg/kg dose of carprofen subcutaneously at 8 hours after premedication. During surgery, blood pressure, heart rate and temperature were assessed every 5 minutes. Postoperatively, sedation scores, temperature, heart rate and Glasgow composite modified pain score - short form were assessed for 12 hours postoperatively., Results: One of 17 (5.9%) dogs had intraoperative hypotension, nine of 17 dogs had intra-operative bradyarrhythmias and 17 of 17 dogs had intra-operative hypothermia. No dogs required intra-operative rescue. Composite modified pain score - short form scores were below the threshold for intervention in 16 of 17 (94.1%) animals. Only one of 17 (5.9%) dogs required rescue analgesia. Median sedation score was 0 by the T8 time point. Adverse events were rare in both groups with only vocalisation and hypothermia reported commonly postoperatively., Clinical Significance: Two doses of methadone at either 0.25 or 0.5 mg/kg administered via subcutaneous injections pre-operatively and 4 hours later, along with 4.4 mg/kg carprofen subcutaneously 8 hours after the first methadone dose appear to provide sufficient pain control for up to 12 hours in dogs undergoing tibial plateau levelling osteotomy., (© 2024 British Small Animal Veterinary Association.)

Background: This study aimed to investigate the possible presence of maladaptive pain in the thoracic limbs of dogs with elbow osteoarthritis (OA) using an electronic von Frey aesthesiometer (eVFA)., Methods: Twenty-eight client- and staff-owned dogs (OA, n = 14; controls, n = 14) were enrolled in the study. Every dog underwent a full orthopaedic examination, and then five von Frey measurements were obtained from each carpal pad of each dog. A maximum test threshold of 400 g was set and approved by an ethics committee., Results: eVFA thresholds were significantly lower (p < 0.001) in dogs with OA (median 248 g, range 128-369 g) than in control dogs (median 390 g, range 371-400 g). In the OA group, the sensory threshold was significantly lower (p = 0.048) in the more severely affected limb than the less severely affected limb., Limitation: The low maximum threshold required for ethical approval may influence the variability in the control group., Conclusions: Dogs with elbow OA had significantly lower sensory thresholds than control dogs, which is compatible with the presence of maladaptive pain, potentially due to central sensitisation. Further research is required to evaluate the potential use of the eVFA for monitoring clinical progression and treatment response in dogs with elbow OA., (© 2024 The Authors. Veterinary Record published by John Wiley & Sons Ltd on behalf of British Veterinary Association.)

Objective: To measure interobserver agreement for 4 functional tasks and their summed geriatric functional score (GFS) and correlate tasks and GFS with client-specific outcome measurements (CSOMs): Canine Brief Pain Inventory (CBPI) pain severity, CBPI pain interference, and Liverpool Osteoarthritis in Dogs., Animals: 89 geriatric dogs were recruited between April and September 2023 from staff, friends, and clients of the Cornell University College of Veterinary Medicine with a median age of 11.0 years and weight of 26.4 kg., Methods: Dogs underwent 4 sequential functional tests: timed up and go (TUG), cavallettis, figure 8s, and down to stands. Two observers independently scored each dog. The GFS was calculated based on the summed scores of the individual tests. Additional information collected included signalment, weight, measurements reflecting the comorbidities of aging (body condition score and muscle condition score), and CSOMs., Results: Strong interrater agreement was found for all functional tests. The TUG in seconds (sTUG) and figure 8s demonstrated significant (P < .05) moderate to strong correlations to all CSOMs. The GFS showed similar significant correlations with all CSOMs except CBPI pain severity; however, when correlating individual tests to CSOMs, only figure 8s and TUG were significantly contributing to GFS results. Receiver operating characteristic curve analysis defined highly functional dogs as those completing the sTUG in under 3.83 seconds. The sTUG represented the best test for geriatric function given it was objective, reliable, correlated well to CSOMs, and could help identify highly functioning dogs., Clinical Relevance: The sTUG appears to be the first practical and reliable functional test of canine geriatric mobility.

Quantitative sensory testing (QST) allows the study of pain mechanisms, patient phenotyping, and response to therapy. The goals of this study were to conduct a systematic review of the use of QST in dogs with musculoskeletal disease including osteoarthritis (OA), and to assess, by means of a meta-analysis, the ability of QST to differentiate affected dogs from healthy controls. The study protocol was registered; three bibliographic databases were screened. Studies involving QST in healthy dogs and those with musculoskeletal disease were included. Data were extracted using a standardized form. Assessment of quality and risk of bias were performed using the CAMARADES critical assessment tool. Twenty-nine articles met the inclusion criteria [systematic review (n = 11); meta-analysis (n = 28)]. In the systematic review, ten studies performed static QST: mechanical [punctate tactile (n = 6); mechanical pressure (n = 5)]; thermal [cold (n = 3); hot (n = 4)]; electrical (n = 1); and one study performed dynamic QST [conditioned pain modulation (n = 1)]. Most studies were of good scientific quality and showed low to moderate risk of bias. A meta-analysis was not possible due to numerous and severe issues of heterogeneity of data among studies. Methods to reduce risk of bias and use of reporting guidelines are some of the most needed improvements in QST research in dogs. Standardization of QST methodology is urgently needed in future studies to allow for data synthesis and a clear understanding of the sensory phenotype of dogs with and without chronic pain including OA., Competing Interests: Conflict of Interest Statement None of the authors has any financial or personal relationships that could inappropriately influence or bias the content of the paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study addresses the refinement and revalidation of a composite pain scale that focuses on equine facial expressions and behavioural indicators as exhibitions of ophthalmic pain. This scale included only Behavioural and Facial and Ocular expression indicators and, compared to the first version of Equine Ophthalmic Pain Scale (EOPS), item descriptors and related ratings were changed. Thirteen horses with ocular diseases that required medical or surgical treatment were enroled (group P). In each animal, the refined EOPS (R-EOPS) was applied prior to any treatment (T0) and one week later (T7). The R-EOPS was applied twice, 7 days apart, to 16 healthy control horses (group C). Two 30-second videos were recorded each time to allow the retrospective analysis by eight observers. Inter-observer reliability of items was moderate or substantial (Krippendorff's alpha, Kα>0.40) while their intra-observer reliability was substantial or almost perfect for most items (Kα ≥0.61). Both inter- and intra-observer reliability of Total Score (TS) were however excellent (Intraclass Correlation Coefficients, ICC>0.75). The TS also showed good reproducibility (Kendall coefficient=0.786, ICC=0.684) and high consistency of its items (Cronbach's α=0.847). The comparison between groups as well as the sensitivity and specificity values supported the validity of the R-EOPS. In particular, for each extra point added to the TS, the risk of the horse having pain increased by more than two times (Odds Ratio=2.079, 95%CI=1.542-2.804; P<0.001). The Receiver Operating Characteristic analysis identified 6 as the threshold value of R-EOPS for discriminating horses with ocular pathology (sensitivity=83%, specificity=100%). This scale may be an effective tool for reliably assessing the pain level in horses with ophthalmic diseases and potentially guiding pain management although it still requires large-scale application and external validation., Competing Interests: Declaration of Competing Interest None of the Authors has any financial or personal relationship that could inappropriately influence or bias the content of the paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: The aim of the study was to evaluate reproducibility and practicality of the German version of the Glasgow composite measured pain scale - feline, during its implementation into a German veterinary hospital., Material and Methods: The study comprised of 2 parts. Participation of veterinary professionals was voluntary. During part 1, 15 staff members (all rater=AR) with variable clinical experience (nurses, interns, junior clinician, senior clinicians), from 4 disciplines (anesthesia, internal medicine, surgery, neurology), and one main investigator (AC), pain scored 45 diseased cats and 10 healthy cats. Part 2 was an online survey, evaluating the practical experience of participants during part 1 and asking for suggestions to improve the scale and process of pain assessment. For part 1 normal distribution of data was tested by Shapiro-Wilk-Test and histograms. Intrarater and interrater reliability were evaluated by calculating the intraclass-correlation. Statistical analysis of part 2 used descriptive methods., Results: The interrater reliability was moderate (ICC AR : 0.59) and the intrarater reliability was good (ICC AC : 0.88). The pain scores of cats with medical (AR: 3.06±2.33, AC 3.52±2.34) and surgical disease (AR: 3.78±2.38, AC: 4.02±2.72) showed no significant difference. All healthy cats were classified as "not painful" (AR: 0.77±0.67, AC: 1.09±0.83). Clinical experience of the rater did not significantly influence pain scores. The GCMPS-F was judged as easy to use and as helpful tool for cats with unclear pain conditions., Conclusion: The GCMPS-F had a good acceptance and moderate interrater reliability., Clinical Relevance: Using the German version of the GCMPS-F, veterinary professionals from different disciplines and with different grades of specialisation can reliably assess pain levels in cats without prior extensive training., Competing Interests: Für keine der Autorinnen liegt ein Interessenkonflikt vor., (Thieme. All rights reserved.)

A number of facial expressions are associated with pain in horses, however, the entire display of facial activities during orthopedic pain have yet to be described. The aim of the present study was to exhaustively map changes in facial activities in eight resting horses during a progression from sound to mild and moderate degree of orthopedic pain, induced by lipopolysaccharides (LPS) administered in the tarsocrural joint. Lameness progression and regression was measured by objective gait analysis during movement, and facial activities were described by EquiFACS in video sequences (n = 348, total length 892.5 min) of the horses obtained when resting in their box stalls. Predictive modeling identified 16 action units and action descriptors, related to ears, eyes, and lower face. Lower lip depressor (AU16), lips part (AU25), half blink (AU47), single ear forward (SEAD101) and single ear rotator (SEAD104) were selected as co-occurring significantly more in horses with pain than in horses without pain. The major change in co-occurring facial activities occurred in the transition from no pain to mild pain. In conclusion, resting horses with induced orthopedic pain showed a dynamic upper and lower facial repertoire and the relationship between level of pain intensity and facial activity appears complex., (© 2023. The Author(s).)

Objective: To use a previously validated veterinary clinical examination sheet, Liverpool Osteoarthritis in Dogs (LOAD) questionnaire, combined with kinetic and kinematic gait analysis in dogs with/without mobility problems to demonstrate the capacity of a novel clinical metrology instrument ("GenPup-M") to detect canine mobility impairments., Design: Quantitative study., Animals: 62 dogs (31 with mobility impairments and 31 without mobility impairments)., Procedure: The dogs' clinical history was obtained from owners and all dogs underwent a validated orthopaedic clinical examination. Mobility impairments were diagnosed in the mobility impaired group based on clinical history and orthopaedic examination. Owners were asked to complete GenPup-M along with a previously validated mobility questionnaire (Liverpool Osteoarthritis in Dogs (LOAD)) to identify construct validity. As a test of criterion validity, the correlation between instrument scores and the overall clinical examination scores, along with force-platform obtained peak vertical forces (PVF) were calculated. GenPup-M underwent internal consistency and factor analysis. Spatiotemporal parameters were calculated for dogs with/without mobility impairments to define the gait differences between these two groups., Results: Principal Component Analysis identified GenPup-M had two components with Eigenvalues >1 ("stiffness/ease of movement" and "willingness to be active/exercise"). Cronbach's α was used to test internal consistency of GenPup-M and was found to be "good" (0.87). There was a strong, positive correlation between GenPup-M and LOAD responses (r2 = 0.69, p<0.001) highlighting construct validity. Criterion validity was also shown when comparing GenPup-M to clinical examination scores (r2 = 0.74, p<0.001) and PVF (r2 = 0.43, p<0.001). Quantitative canine gait analysis showed that there were statistically significant differences between peak vertical forces (PVF) of mobility impaired and non-mobility impaired dogs (p<0.05). Analyses of PVF showed that non-mobility impaired dogs more evenly distributed their weight across all thoracic and pelvic limbs when compared to mobility impaired dogs. There were also consistent findings that mobility impaired dogs moved slower than non-mobility impaired dogs., Conclusion and Clinical Relevance: GenPup-M is a clinical metrology instrument (CMI) that can be completed by dog owners to detect all mobility impairments, including those that are early in onset, indicating the versatility of GenPup-M to assess dogs with and without mobility impairments. Results of the study found that GenPup-M positively correlated with all three objective measures of canine mobility and consequently showed criterion and construct validity. Owner-reported CMIs such as GenPup-M allow non-invasive scoring systems which veterinary surgeons and owners can use to allow communication and longitudinal assessment of a dog's mobility. It is anticipated that GenPup-M will be used by owners at yearly vaccinations/health checks, allowing identification of any subtle mobility changes, and enabling early intervention., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Clark et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objectives: The aim of the present study was to investigate the construct validity, responsiveness and reliability of the Feline Grimace Scale (FGS) in kittens., Methods: A total of 36 healthy female kittens (aged 10 weeks to 6 months) were included in a prospective, randomized, blinded study. Video recordings of all kittens were made before and 1 and 2 h after ovariohysterectomy using an opioid-free injectable anesthetic protocol with or without multimodal analgesia. Additional recordings were taken before and 1 h after administration of rescue analgesia (buprenorphine 0.02 mg/kg IM) to painful kittens. Screenshots of facial images were collected from the video recordings for FGS scoring. Four observers blinded to treatment groups and time points scored 111 randomized images twice with a 5-week interval using the FGS. Five action units (AUs) were scored (ear position, orbital tightening, muzzle tension, whiskers position and head position; 0-2 each). Construct validity, responsiveness, and inter- and intra-rater reliability were evaluated using linear models with Benjamini-Hochberg correction, Wilcoxon signed-rank test and single intraclass correlation coefficients (ICC single ), respectively ( P <0.05)., Results: FGS total ratio scores were higher at 1 and 2 h after ovariohysterectomy (median [interquartile range, IQR]: 0.30 [0.20-0.40] and 0.30 [0.20-0.40], respectively) than at baseline (median [IQR]: 0.10 [0.00-0.30]) ( P <0.001). FGS total ratio scores were lower after the administration of rescue analgesia (median [IQR] before and after rescue analgesia) 0.40 [0.20-0.50] and 0.20 [0.10-0.38], respectively ( P <0.001). Inter-rater ICC single was 0.68 for the FGS total ratio scores and 0.35-0.70 for all AUs considered individually. Intra-rater ICC single was 0.77-0.91 for the FGS total ratio scores and 0.55-1.00 for all AUs considered individually., Conclusions and Relevance: The FGS is a valid and responsive acute pain-scoring instrument with moderate inter-rater reliability and good to excellent intra-rater reliability in kittens., Competing Interests: Conflict of interestThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Background: Injectable non-steroidal anti-inflammatory drugs (NSAIDs) are commonly prescribed to queens undergoing ovariohysterectomy (OVH), but the requirement for postoperative administration is unclear and practices vary. Existing studies assessing efficacy rely on pain scoring by experienced clinicians. However, following OVH, most cats are discharged within hours of recovery., Methods: Cats undergoing OVH were randomly assigned to two treatment groups: MEL and ROB. Cats in the MEL group (n = 76) received meloxicam (0.2 mg/kg) and those in the ROB group (n = 65) received robenacoxib (2 mg/kg). Owners were contacted by a blinded assessor 3 days postoperatively and asked to identify physical or behavioural changes and to assign pain scores using a numerical rating scale., Results: More cats in the ROB group displayed abnormal behaviours than cats in the MEL group (p = 0.03). Most owners assigned a pain score of 0 (72%) (n = 101), but pain scores were significantly higher in the ROB group than in the MEL group (p = 0.005)., Limitation: Methods of owner assessment of pain in cats have not been validated., Conclusions: Both meloxicam and robenacoxib are effective in controlling postoperative pain. Meloxicam may have improved efficacy in certain patient populations. Applying a blanket approach to prescribing NSAIDs to cats undergoing OVH postoperatively may not be necessary. This has safety, environmental and cost implications., (© 2023 The Authors. Veterinary Record published by John Wiley & Sons Ltd on behalf of British Veterinary Association.)

Background: The objective of this study was to determine the threshold of the Bristol Rabbit Pain Scale (BRPS) indicating the need for intervention analgesia., Methods: Fourteen members of veterinary staff were recruited to rate rabbits (n = 71) in acute pain. Observers in group A (n = 7) were asked to score each rabbit using the BRPS, while observers in group B (n = 7) independently answered the question 'In your clinical capacity, do you think this animal requires analgesia?' with either 'Yes' or 'No'. The answers from the two groups were then compared., Results: Rabbits for which group B answered 'No' (n = 36) had a median BRPS score (range) of 4 (0-10), while those for which group B answered 'Yes' (n = 42) had a median BRPS score of 9 (1-18; Z = -7.48; p < 0.001). The area under the receiver operating characteristic curve was 0.85 (95% confidence interval: 0.77-0.93; p < 0.001), indicating excellent discrimination of the BRPS with a cut-off score of 5.5 (sensitivity 88.1% and specificity 69.4%). However, for practicality, a score of 5 was deemed a feasible cut-off., Limitations: The main limitations of this study are the small rabbit sample size and the subjective nature of pain scoring in animals., Conclusions: Analgesic intervention should be considered in rabbits with a pain score equal to or greater than 5 on the BRPS., (© 2023 British Veterinary Association.)

Objective: To compare pain perception between gonadectomized and intact dogs., Study Design: Blinded, prospective, cohort study., Animals: A group of 74 client-owned dogs., Methods: Dogs were divided into four groups: group 1-female/neutered (F/N), group 2-female/intact (F/I), group 3-male/neutered (M/N) and group 4-male/intact (M/I). Premedication consisted of intramuscularly administered acepromazine (0.05 mg kg -1 ) and morphine (0.2 mg kg -1 ), and subcutaneously administered carprofen (4 mg kg -1 ). Anaesthesia was induced with propofol (1 mg kg -1 intravenously and supplementary doses to effect) and maintained with isoflurane in 100% oxygen. Intraoperative analgesia was achieved with fentanyl infusion (0.1 μg kg -1 minute -1 ). Pain assessments [using the University of Melbourne Pain Scale (UMPS) and an algometer at the incision site (IS), parallel to the incision site (NIS), and on the contralateral healthy limb] were performed preoperatively, and at 1, 2, 4, 6, 9 and 20 hours after extubation. The time-standardised area under the curve (AUCst) for measurements was calculated and compared by performing a one-way multivariate analysis of variance (manova). Statistical significance was set at p < 0.05., Results: Postoperatively, F/N exhibited higher pain than F/I, with estimated marginal means (95% confidence intervals) AUCstIS Group1 909 (672-1146) versus AUCstIS Group2 1385 (1094-1675) (p = 0.014), AUCstNIS Group1 1122 (823-1420) versus AUCstNIS Group2 1668 (1302-2033) (p = 0.024) and AUCstUMPS Group1 5.30 (4.58-6.02) versus AUCstUMPS Group2 4.1 (3.2-5.0) (p = 0.041). Similarly, M/N showed higher pain than M/I with AUCstIS Group3 686 (384-987) versus AUCstIS Group4 1107 (871-1345) (p = 0.031) and AUCstNIS Group3 856 (476-1235) versus AUCstNIS Group4 1407 (1109-1706) (p = 0.026), and AUCstUMPS Group3 6.0 (5.1-6.9) versus AUCstUMPS Group4 4.4 (3.7-5.2) (p = 0.008)., Conclusions and Clinical Relevance: Gonadectomy affects pain sensitivity in dogs undergoing stifle surgery. Neutering status should be taken into consideration when planning individualized anaesthetic/analgesic protocols., (Copyright © 2023 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Over 95% of veterinarians report believing that dog breeds differ in pain sensitivity. Ratings made by veterinarians differ from those of the general public, suggesting these beliefs may be learned during veterinary training or clinical experiences. Therefore, the current study's primary objective was to evaluate dog breed pain sensitivity ratings during veterinary training and compare these ratings to those of the general public and undergraduates in animal-health related fields. Using an online survey, members of the general public, undergraduates, veterinary students across all four years, and veterinary faculty and staff rated pain sensitivity of 10 different dog breeds, identified only by their pictures. Compared to the general public and undergraduates, veterinary students rated pain sensitivity across breeds of dog more similarly to veterinary faculty and staff. Further, when undergraduates had clinical experience, they also rated certain dog breeds in a similar way to the veterinary students and professionals. Our findings suggest that veterinary education and clinical experiences influence pain sensitivity ratings across dog breeds. Future research should identify how these pain sensitivity beliefs are communicated and whether these beliefs affect recognition and treatment of pain by veterinarians., (© 2023. Springer Nature Limited.)

Objectives: Pain assessment in veterinary medicine is challenging. Uncertainty in the ability to recognise pain in animals contributes to suboptimal analgesia. Pain scales have been developed to aid in pain recognition. It is unknown if such scales are routinely utilised in veterinary practices., Materials and Methods: A survey using RedCap software was emailed to veterinarians and veterinary technicians working in practices across the USA. This study aimed to investigate whether pain scoring was routinely performed and reasons to use or not use pain scales. One hundred and forty-four participants were required to estimate prevalence (95% confidence level, 5% precision) with hypothesised prevalence of approximately 10%., Results: One hundred and forty-seven participants completed the survey. Seventy (47.6%) responded that pain scoring was performed in their practices, 24 (16.3%), reported "sometimes" and 53 (36.1%) reported pain scores were not performed. Reasons for not pain scoring included no training (51.9%) and busy caseload (48.1%). Disadvantages of pain scales were unreliability (16/82; 20%), duration required for completion (14/82; 17%) and vocalisation (14/82; 17%)., Clinical Significance: Almost 50% of the small animal practices surveyed reported the use of pain scales as part of their routine workflow. However, many practices still do not consistently utilise pain scales to assess pain in dogs and cats. Perceived unreliability and lack of compliance were reasons for this result. Improvement of training and proper pain scale introduction and implementation in small animal practices in the USA appears to be required., (© 2022 British Small Animal Veterinary Association.)

Objectives: This study compared an opioid-free injectable anaesthetic protocol with or without multimodal analgesia in kittens undergoing ovariohysterectomy., Methods: In this prospective, randomised, blinded, clinical trial, 29 healthy kittens (mean ± SD weight 1.55 ± 0.46 kg; aged 10 weeks to 6 months) were included. Anaesthesia was performed with an intramuscular injection of ketamine (4 mg/kg), dexmedetomidine (40 μg/kg) and midazolam (0.25 mg/kg). In the multimodal group (MMG), cats (n = 14) received meloxicam (0.1 mg/kg SC) and intraperitoneal bupivacaine 0.25% (2 mg/kg), whereas the same volume of saline was administered in the control group (CG; n = 15). Atipamezole (0.4 mg/kg IM) was given 15 mins after ovariohysterectomy. Postoperative pain was assessed using the UNESP-Botucatu multidimensional feline pain assessment scale - short form. Rescue analgesia (buprenorphine 0.02 mg/kg IM in MMG/CG and meloxicam 0.1 mg/kg SC in CG) was administered if pain scores were ⩾4/12. Soft food intake (after 2 and 60 mins) was evaluated at specific time points postoperatively. Statistical analyses were performed with linear models and post-hoc pairwise comparison with Benjamini-Hochberg corrections ( P <0.05)., Results: The prevalence of rescue analgesia was higher in the CG (n = 15/15) than the MMG (n = 1/14; P <0.001). Pain scores at 1 h, 2 h and 4 h postoperatively were higher in the CG (4.1 ± 2.8, 4.8 ± 3.0 and 5.3 ± 1.2, respectively) than in the MMG (1.6 ± 1.0, 1.1 ± 1.0 and 0.9 ± 0.8, respectively; P <0.001). Food intake (%) at 1 h postoperatively was higher in the MMG after 2 and 60 mins (10.4 ± 9 and 71.9 ± 29, respectively) than in the CG (1.4 ± 2 and 13.9 ± 7, respectively; P <0.001)., Conclusions and Relevance: This opioid-free protocol using multimodal analgesia produced adequate postoperative pain relief, while almost eliminating the need for rescue analgesia in kittens undergoing ovariohysterectomy. Pain decreased food intake.

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 challenging, compounded by rabbits being a prey species that display freezing behavior in the presence of unfamiliar caregivers. Here we discuss some key changes in rabbits that can be used in the assessment of pain and provide some practical suggestions to ensure that the assessment can be carried out effectively., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Recognition and accurate assessment of the severity of pain can be challenging in ferrets as they are unable to verbally communicate, and often hide their pain. Pain assessment relies on the assessment of behavioral, physiologic, and other clinical parameters that serve as indirect indicators of pain. Assessment of physiologic and clinical parameters requires handling, which results in changes in these parameters. Behavioral parameters can be assessed less invasively by observing the patient. Due to their nonspecificity, correct interpretation may be challenging. Just as in other species, a grimace scale seems to be the most helpful tool in recognizing pain in ferrets., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Ferrets often require pain management as part of comprehensive veterinary care. Recognition and objective quantification of pain, such as the ferret grimace scale, are the first steps of an analgesic plan. As in other species, a multimodal approach to pain management is preferred, which includes combining analgesic drugs of multiple classes and/or techniques to affect different areas of the pain pathway. This article reviews the current published literature on analgesic medications in domestic ferrets, including specific drugs, doses, dosing intervals, and routes of administration., Competing Interests: Disclosure The authors have nothing to disclose., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Rabbits occupy facets of veterinary medicine spanning from companion mammals, wildlife medicine, zoologic species, and research models. Therefore, analgesia is required for a variety of conditions in rabbits and is a critical component of patient care. Considerations when selecting an analgesic protocol in rabbits include timing of administration, route of administration, degree or anticipated pain, ability to access or use controlled drugs, systemic health, and any potential side effects. This review focuses on pharmacologic and locoregional management of pain in rabbits and emphasizes the need for further studies on pain management in this species., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objectives: This study aimed to investigate if cat caregivers could reliably assess acute pain using the Feline Grimace Scale (FGS), and if participant demographics could affect scores., Methods: An online survey in English and Spanish was advertised by International Cat Care and other platforms (March-May 2021) using convenience sampling. Eligible participants were caregivers >18 years old and non-veterinary health professionals. Participants and a group of eight veterinarians scored 10 images of cats with different levels of pain. Data were analysed using linear models and intraclass correlation coefficient (ICC; α <0.05). Interpretation of the ICC was <0.2 = poor; 0.21-0.4 = reasonable; 0.41-0.60 = moderate; 0.61-0.80 = good; and 0.81-1.0 = very good., Results: A total of 3039 responses were received with 1262 completed answers from 66 countries (86%, 11.1% and 2.9% identified as female, male or other, respectively). Scores for each action unit (AU; ear position, orbital tightening, muzzle tension, whiskers change and head position) and their sum (FGS score) were not significantly different between caregivers and veterinarians, except for muzzle (caregivers 0.9 ± 0.0; veterinarians 0.7 ± 0.1; P  = 0.035). The ICC single (caregivers) was 0.65, 0.69, 0.58, 0.37, 0.38 and 0.65, respectively, for AU ears, eyes, muzzle, whiskers, head and sum of scores. Demographic variables did not affect FGS scores., Conclusions and Relevance: Total FGS scores had good reliability when used by cat caregivers, regardless of demographic variables, showing the potential applicability of the instrument to improve feline pain management and welfare worldwide.

The recognition and assessment of pain in avian species are crucial tools in providing adequate supportive care in clinical, laboratory, zoologic, rehabilitation, and companion animal settings. With birds being a highly diverse class of species, there is still much to be determined regarding how to create specific criteria to recognize and assess pain in these animals. This article provides a clinical review on the physiology of pain in birds, observed behavioral and physiologic alterations with pain, how different sources and degrees of pain can alter behaviors observed, and how this information can be applied in a clinical setting., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Available methods for recognizing and assessing pain in rodents have increased over the last 10 years, including the development of validated pain assessment scales. Much of this work has been driven by the needs of biomedical research, and there are specific challenges to applying these scales in the clinical environment. This article provides an introduction to pain assessment scale validation, reviews current methods of pain assessment, highlighting their strengths and weaknesses, and makes recommendations for assessing pain in a clinical environment., (Copyright © 2023 Elsevier Inc. All rights reserved.)

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 ) in the presence and absence of an observer. Videos were assessed twice in random order by 3 evaluators who were blind to the collection time and the presence or absence of an observer. Responses to pain and analgesia were evaluated by comparing the 4 time points using the Friedman test, followed by the Dunn test. The influence of the presence or absence of the observer at each time point was evaluated using the Wilcoxon test. Intra- and interrater reliabilities were estimated using the intraclass correlation coefficient. The scale was responsive to pain, as the scores increased after surgery and had decreased by 24 h after surgery. The presence of the observer reduced significantly the RbtGS scores (median and range) at pain (present, 0.75, 0 to 1.75; absent, 1, 0 to 2) and increased the scores at baseline (present, 0.2, 0 to 2; absent, 0, 0 to 2) and 24h after surgery (present, 0.33, 0 to 1.75; absent, 0.2, 0 to 1.5). The intrarater reliability was good (0.69) to very good (0.82) and interrater reliability was moderate (0.49) to good (0.67). Thus, the RbtGS appeared to detect pain when scored from video footage of rabbits before and after orthopedic surgery. In the presence of the observer, the pain scores were underestimated at the time considered to be associated with the greatest pain and overestimated at the times of little or no pain.

Objective: To perform the initial psychometric evaluation of the Portuguese version of the Canine Brief Pain Inventory (CBPI)., Animals: A total of 100 dogs, 50 with bilateral hip osteoarthritis and 50 unaffected dogs., Procedures: The 2 groups of dogs were assessed using the CBPI. The English version of the CBPI (divided into a pain severity score and a pain interference score) was translated into Portuguese, and a copy of the translated version was completed by native Portuguese speakers' canine handlers. The results from the 2 groups were compared, and psychometric properties were evaluated. Construct validity was evaluated by assessing differences between animals with osteoarthritis and unaffected animals with the Mann-Whitney test. Further evaluation was performed with the Kaiser-Meyer-Olin measure of sampling adequacy, Eigenvalue, and scree-plot analysis. Internal consistency was tested with Cronbach α., Results: A significant difference was observed between dogs with osteoarthritis and unaffected dogs in pain severity and pain interference scores (P < .01 for both), one indication of construct validity. Cronbach α was 0.99, and a high interitem correlation was observed, showing strong internal consistency. One factor accounted for 92.3% of the total variance., Clinical Relevance: We presented the initial validation of the Portuguese version of the CBPI and its validity in the Portuguese language. It is an essential step in providing a valid tool for clinicians to assess pain in dogs with osteoarthritis. Further studies are required to determine if the present results can be replicated across samples with different characteristics and evaluate response to treatment.

Objective: To develop and begin establishing evidence for validity of an instrument to assess the quality of induction in dogs., Study Design: Cross-sectional survey and video scoring., Animals and Population: A total of 51 veterinary anesthesia personnel, four board-certified anesthesiologists and videos of induction of anesthesia in 18 dogs., Methods: In Part 1, an online survey was sent to veterinary anesthesia personnel to solicit expressions and words that they associate with induction of anesthesia. These expressions were evaluated by four anesthesiologists to create a composite scale (Auburn Induction Scale). In Part 2, 18 videos were reviewed by the same four anesthesiologists on two separate occasions. The videos were scored using the Auburn Induction Scale, a simple descriptive scale (SDS) and a visual analog scale (VAS). Intra-rater and inter-rater reliability was measured using an intraclass correlation coefficient (ICC). Significance was set at p < 0.05., Results: The survey yielded 51 responses that were condensed into 133 expressions. The four anesthesiologists created 18 items incorporating the 133 expressions. The mean ± standard deviation intra-rater reliability ICC was 0.81 ± 0.08 for the Auburn Induction Scale, 0.71 ± 0.02 for the SDS and 0.71 ± 0.08 for the VAS for all raters. The mean ± standard deviation inter-rater reliability ICC was 0.69 ± 0.04 for the Auburn Induction Scale, 0.61 ± 0.05 for the SDS and 0.60 ± 0.06 for the VAS., Conclusions and Clinical Relevance: In a research setting, widespread use of this scale may be helpful in increasing the accuracy of data and improving agreement between studies assessing induction of anesthesia in dogs. The results of this study have yielded a composite scale that is more reliable between and among raters than a unidimensional scale., (Copyright © 2022 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Background: Understanding factors influencing assessment of pain in horses will facilitate communication between veterinarians and horse owners., Objectives: To compare estimates of pain experienced by horses as provided by veterinarians and horse owners and to determine factors associated with individuals who perceive horses to be experiencing extreme pain or minimal pain., Study Design: Cross-sectional study., Methods: Internet-based questionnaires for horse owners and veterinarians included items related to recognition of pain in horses, estimated degree of pain experienced by horses, and demographic information. Variables associated with perception of a high or low degree of pain were investigated using logistic regression analyses., Results: Final data sets included responses from 553 horse owners and 263 veterinarians. Pain scores varied widely and differences in median scores from horse owners and veterinarians were small. Horse owners providing high pain ratings were more likely to have <10 horses (odds ratio [OR] = 2.0, 95% CI = 1.1-3.5) and to not have a college degree (OR = 1.5, 95% CI = 1.0-2.2). Those providing low pain ratings were less likely to own <10 horses (OR = 0.6, 95% confidence interval [CI] = 0.4-0.9). Veterinarians providing high pain ratings were more likely to be employed in a mixed animal practice (OR = 2.8, 95% CI = 1.3-5.9) and to lack board-certification in a veterinary specialty (OR = 2.1, 95% CI = 1.1-4.2). Veterinarians providing low pain ratings were more likely to be male (OR = 2.4, 95% CI = 1.3-4.2)., Main Limitations: The respondent population may be biased because of the method of questionnaire distribution and associated sampling bias. Respondents were primarily from the United States., Conclusions: Assessments of the degree of pain horses are experiencing vary widely among horse owners and equine veterinarians., (© 2022 EVJ Ltd.)

Objective: To compare the effects of hydromorphone and butorphanol in horses undergoing arthroscopy and describe the pharmacokinetics of hydromorphone in anesthetized horses., Study Design: Randomized controlled clinical trial., Animals: A total of 40 adult horses admitted for elective arthroscopy., Methods: Horses were randomly assigned to be administered intravenous hydromorphone (0.04 mg kg -1 ; group TxH; n = 19) or butorphanol (0.02 mg kg -1 ; group TxB; n = 21) prior to surgery as part of a standardized anesthetic protocol. Pain was scored by two observers unaware of group assignment using the Equine Utrecht University Scale for Facial Assessment of Pain (EQUUS-FAP) and a composite pain scale (CPS) prior to surgery (baseline), 2 hours (P2) and 4 hours (P4) following recovery from anesthesia. Blood samples were collected at various time points for determination of plasma hydromorphone concentration using liquid chromatography-tandem mass spectrometry. Data were analyzed with a mixed-effect model., Results: Median (range) baseline EQUUS-FAP was 1.2 (0.0-4.0) with no effect of group, time points or interaction. Baseline CPS was similar between groups. Group TxH baseline CPS was 2.5 (0.0-10.0), increased at P2 [4.5 (0-10.0); p = 0.046] and returned to baseline values at P4 [3.0 (0.0-11.0)]. Group TxB baseline CPS was 2.0 (0.0-8.0), increased at P2 [3.5 (0.0-11.0); p = 0.009] and P4 [5.0 (0.0-11.0); p < 0.001]. Pharmacokinetic terminal half-life was 774 ± 82.3 minutes, area under the curve was 1362 ± 314 ng minutes mL -1 , clearance was 30.7 ± 7.23 mL minute -1 kg -1 and volume of distribution at steady state was 884 ± 740 mL kg -1 ., Conclusions: Hydromorphone, but not butorphanol, decreased CPS back to baseline at P4 after recovery., Clinical Relevance: Hydromorphone may provide superior postoperative analgesia compared with butorphanol in horses undergoing arthroscopy., (Copyright © 2022 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.)

Objectives: To investigate the diagnostic value of an owner-completed canine osteoarthritis screening checklist to help identify previously undiagnosed osteoarthritis cases, and assess their response to carprofen treatment by monitoring pain and functional mobility., Materials and Methods: Dogs (n=500) whose owners reported ≥1 positive response to the osteoarthritis checklist were examined to identify dogs with previously undiagnosed osteoarthritis. Eligible dogs (n=133) were evaluated for pain and video mobility analysis by Helsinki Chronic Pain Index and visual analogue scale scores, respectively, following carprofen treatment, administered for 30 days (n=95) or up to 120 days (n=38). Dogs were filmed at clinics performing activities (walking, jogging, sitting/lying, walking up and down stairs), and scored at days 0, 30 and 120 using visual analogue scale by an independent blinded expert., Results: A diagnosis of osteoarthritis was confirmed by a veterinarian in 38% (188 of 500) of dogs. Balance of sensitivity and specificity across the original group of nine screening questions was optimised to approximately 88 and 71%, respectively, after elimination of three questions. Pain measured by Helsinki Chronic Pain Index and functional mobility improved over time in response to treatment with carprofen. Mean ability scores for activities significantly improved between days 0 and 30 for walking, jogging, sitting/lying and walking down stairs, and days 0 and 120 for sitting/lying and walking up stairs., Clinical Significance: More osteoarthritis cases were identified in study dogs than previous prevalence estimates, indicating the screening checklist's potential to help identify for further evaluation cases that could otherwise remain undiagnosed. Improvements in function were demonstrated after carprofen treatment., (© 2022 Zoetis Inc. Journal of Small Animal Practice published by John Wiley & Sons Ltd on behalf of British Small Animal Veterinary Association.)

Objective: To evaluate the duration and analgesic quality of bupivacaine mixed with dexmedetomidine (BUP-DEX) or bupivacaine liposome suspension (BLS) administered as a transverse abdominis plane (TAP) block, compared with a negative control (no TAP block; CTRL) in dogs., Animals: 26 mixed-breed shelter dogs undergoing elective ovariohysterectomy between January 28 and December 8, 2020., Procedures: Each dog was randomly assigned to receive either an ultrasound-guided TAP block with either BUP-DEX or BLS or to receive no TAP block at time 0 after induction of general anesthesia. Superficial and abdominal wall pain scores were evaluated before time 0 and at 4, 6, 12, 24, 48, 72, and 96 hours later. Additionally, sedation scores and time to return of various behaviors, such as eating or drinking, were compared., Results: The CTRL group had significantly greater pain scores than the BUP-DEX and BLS groups, but no differences were found between the BUP-DEX and BLS groups. Postoperatively, significantly more dogs needed rescue analgesia and the time to need it was shorter for the CTRL group, compared with the BUP-DEX or BLS groups. Additionally, the CTRL group had greater sedation scores than the other 2 groups. No significant differences were observed in any of the evaluated outcome variables such as eating or drinking., Clinical Relevance: A TAP block appeared to provide adequate postoperative analgesia for abdominal surgery in the dogs of the present study undergoing elective ovariohysterectomy. The BLS TAP block did not appear to provide any extra benefit beyond what BUP-DEX TAP block added under these specific conditions.

Objective: The Glasgow Feline Composite Measure Pain Scale (CMPS-F) is a validated cat pain assessment tool for clinical use. No research has examined how training impacts use of this tool. Thus, we examined whether seminar-style training improves the identification of cat pain when using the CMPS-F. Veterinarians ( n = 17) and non-veterinarian staff ( n = 33; N = 50) were recruited to participate., Procedure: Seminars included: i) pre-training use of the CMPS-F to score cat videos with varying degrees of pain; ii) cat pain assessment training; and iii) post-training use of the CMPS-F. Participant CMPS-F ratings were compared to experts' ratings of the same videos. Average CMPS-F scores and analgesic decision ratings were compared pre-and post-training., Results: Most participants were female non-veterinarian staff who had not heard of the CMPS-F. Participant and expert analgesic decision-making did not differ pre- ( P = 1.0) and post-training ( P = 0.1). In addition, analgesic decision-making was similar between participants and experts for all but 3/20 videos., Conclusion and Clinical Relevance: Seminar training may not be necessary for efficacious use of the CMPS-F. Further research is needed to explore strategies for improving awareness of cat pain assessment tools and increasing in-clinic use., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

The objective of this study was to design and assess the validity and reliability of a new feline multiparametric sedation scale (FMSS). A total of 89 household cats were recruited, enabling a total of 534 sedation assessments. Every assessment was performed by 3 blinded observers with varying expertise levels (Level 1: Student; Level 2: RVT; Level 3: ACVAA diplomate or senior resident). For comparison purposes, a visual analogue scale (VAS) and a Simple Qualitative Scale (SQS) were also used concurrently, with the VAS considered the gold standard. The new scale had excellent inter-observer agreement among experience groups with weighted Kappa scores of 0.84 (Levels 1 versus 2), 0.82 (Levels 2 versus 3), and 0.84 (Levels 1 versus 3), with P < 0.0001 for all comparisons. There was a high degree of association between FMSS and VAS ( r = 0.90, P < 0.0001) and between FMSS and SQS ( r = 0.89, P < 0.0001). Final FMSS numerical values were paired with levels of sedation with None = 0 (0 to 5), Mild = 4 (1 to 7), Moderate = 6 (2 to 10), and Profound = 12 (7 to 12); furthermore, differences were detected between pre- and post-sedation evaluations ( P = 0.001). This scale demonstrated internal consistency and sensitivity even when evaluating drugs or doses with minimal sedative effects and there was very strong interrater reliability, independent of experience level. Based on this clinical study, we concluded that the use of this sedation scale is appropriate when objective numerical sedation quantification is required, in either a clinical or research setting., (Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.)

Objectives: The aim of this study was to evaluate the use of mechanical thresholds (MT), measured with the SMALGO (Small Animal ALGOmeter), and to determine whether there was a correlation between MT and Glasgow Feline Composite Measure Pain Scale (CMPS-Feline) scores in cats undergoing ovariohysterectomy., Methods: Client-owned cats undergoing flank ovariohysterectomy were recruited. Pain scores for the pre- and postoperative periods were obtained using the CMPS-Feline in each cat by two independent investigators (A and B). Following CMPS-Feline scoring, MT were measured with the SMALGO, in the surgical area, pre- and postoperatively, only by investigator A. Each cat served as its own control for the comparison of pre- and postoperative variables. Reliability statistics were used to assess the level of inter-observer agreement (A vs B) with respect to pre- and postoperative CMPS-Feline scores, while Spearman's correlation statistics were used to analyse the relationship between MT and CMPS-Feline scores., Results: Twenty-nine cats completed the study. Preoperative MT (340 g [range 108-691]) were significantly higher than postoperatively (233 g [range 19-549]; P  = 0.001). CMPS-Feline scores were not found to differ significantly between the preoperative period (2 [range 0-7] for investigator A and 3.2 ± 2.3 for investigator B) and postoperative period (2 [range 0-10] for investigator A and 3 [range 0-8] for investigator B) for either investigator. Reliability statistics revealed that the level of inter-observer agreement with respect to CMPS-Feline was fair for the preoperative assessments but poor for the postoperative evaluations. There was no correlation between MT and CMPS-Feline scores., Conclusions and Relevance: Although there was no correlation with CMPS-Feline scores performed at the same timepoint, MT increased postoperatively vs baseline. Assuming that, despite analgesia, susceptibility of the surgical area to mechanical stimulation would increase after surgery, this finding suggests that MT might be useful to assess feline surgical pain. The poor level of inter-observer agreement with respect to postoperative CMPS-Feline scores highlights the potential limitations of this scale.

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 orthopaedic and soft tissue surgeries), 'pain' (after surgery), 'analgesia' (after analgesic), and '24h post' (24 hours after surgery). The videos were randomised and assessed twice by four evaluators, within one-month interval between evaluations. After content validation, RBPS was further refined using the criteria from the validation. According to the principal component analysis, RPBS was considered unidimensional. The intra- and inter-observer reliability was excellent (ICC>0.80) for all evaluators. There was a high Spearman's correlation of the RPBS with unidimensional scales (>0.80) and a moderate correlation with the Rabbit Grimace Scale (0.68), confirming criterion validity. According to the mixed linear model, the scale was responsive, shown by the increase in pain scores after surgery. Construct validity was confirmed by known-group approach and internal relationships among items. Adequate item-total correlation (>0.3) was observed for all items, except for the attention to the affected area (0.04). The internal consistency was very good (Cronbach's α coefficient = 0.78; Mcdonald's ω coefficient = 0.83). The cut-off score for rescue analgesia was ≥3, with an area under the curve >0.95, demonstrating a high discriminatory capacity of the instrument. Scores 3 and 4 were within the uncertainty diagnostic zone. Specificity was 87% and sensitivity was 90%. It was concluded that the RPBS presented content, criterion, and construct validities, responsiveness, and reliability to assess acute pain in rabbits submitted to orthopaedic and soft tissue surgeries. The cut-off for rescue analgesia serves as a basis for the administration of analgesics to rabbits submitted to painful procedures., Competing Interests: The authors have declared that no competing interests exist.