American journal of veterinary research最新文献

Objective: The objectives of this study were to evaluate whether the topical application of a maternal bovine (Bos taurus)-appeasing substance (mBAS) to laboratory dogs (Canis familiaris) would affect barking intensity, alter the prevalence of loud barking, or have adverse effects.

Methods: A controlled experiment with a repeated-measures design was performed with a convenience sample of 12 dogs from an existing research colony. The room housing the dogs served as the experimental unit across two 5-day treatment periods (one period for control and one for mBAS). A decibel meter recorded sound levels every 30 s to quantify barking intensity. Dogs with clinical signs of illness were excluded.

Results: A total of 22,502 decibel readings were recorded, and mBAS did not significantly affect decibel levels regardless of time of day or research day. Additionally, mBAS did not significantly affect loud barking. No adverse effects were noted, and no dogs were excluded from the study.

Conclusions: Our results suggest that mBAS does not meaningfully reduce vocalizations in kenneled laboratory dogs nor does it offer welfare benefits to dogs or human caretakers. The substance is well tolerated in this species and may be considered for future research endeavors in interspecies pheromonal communication.

Clinical relevance: Species-specific maternal pheromones can reduce stress-associated behaviors in animals, including vocalization intensity and frequency in dogs. Existing research suggests that interspecies pheromone use is beneficial, and while our data did not support this hypothesis, they contribute to the scientific understanding of this underexplored research area.

Objective: To measure intersegmental movement in the sagittal, dorsal, and transverse planes of the cranial thoracic to caudal thoracic, caudal thoracic to lumbar, and lumbar to sacral segments using range of motion and angular velocity as measures of quality of movement.

Methods: 6-degrees-of-freedom spinal motion was measured at the walk and trot in 3 sound Thoroughbred and Thoroughbred cross horses, and the data were pooled, giving a total of 54 gait cycles at walk and 33 at trot. These were compared against 8 cycles at walk and 13 at trot from 1 Thoroughbred horse that was confirmed as having moderate to severe impact and push-off lameness in the right hind limb.

Results: Both joint angles and angular velocities detected differences between the sound horses and the lame horse, with angular velocity showing notably greater differences in absolute values and percentages compared with joint angles.

Conclusions: The between-group differences indicated decreased quality of movement/control in the lame horse, and this was most apparent when trotting.

Clinical relevance: Intersegmental angular velocity is measured noninvasively and may be used to assess the quality of intersegmental movement in horses as it does in humans. Further investigation to assess angular velocity throughout treatment of topline dysfunction of the horse and its association with different lameness patterns is warranted.

Objective: To develop vertebral heart size (VHS) and vertebral left atrial size (VLAS) reference intervals in sighthounds.

Methods: Electronic medical records of IDEXX Telemedicine Consultants were searched for Rhodesian Ridgebacks, Borzois, Afghan Hounds, Salukis, and Basenjis undergoing thoracic radiography from January 1, 2021, through April 30, 2023. All measurements of VHS and VLAS were performed by the same board-certified cardiologist.

Results: 920 sighthounds (225 Rhodesian Ridgebacks, 196 Borzois, 190 Afghan Hounds, 159 Salukis, and 150 Basenjis) were identified, and 240 (56 Rhodesian Ridgebacks, 47 Borzois, 44 Afghan Hounds, 44 Salukis, and 49 Basenjis) met the inclusion criteria. The remaining 680 dogs were excluded because of malpositioning or incomplete radiographic studies (n = 456), extracardiac disease (139), or cardiac disease (85). The overall reference intervals for all 240 sighthounds were 9.0 to 11.2 vertebrae (v) for VHS and 1.7 to 2.6v for VLAS. Reference intervals were further determined by breed: Rhodesian Ridgeback, 9.3 to 11.5v for VHS and 1.8 to 2.4v for VLAS; Borzois, 8.8 to 10.9v for VHS and 1.7 to 2.3v for VLAS; Afghan Hound, 9.0 to 11.5v for VHS and 1.8 to 2.5v for VLAS; Salukis, 9.4 to 11.8v for VHS and 1.6 to 2.6v for VLAS; and Basenjis, 9.0 to 11.6v for VHS and 1.7 to 2.5v for VLAS.

Conclusions: Sighthounds have breed-specific VHS and VLAS reference intervals.

Clinical relevance: The reference ranges presented here could be a diagnostic aid to screen for cardiomegaly in these breeds.

Objective: To evaluate the current euthanasia procedures of Flemish veterinarians in companion animal veterinary practice.

Methods: An online survey was distributed to veterinarians in Flanders (Belgium) through social media, veterinary websites, and email. The questionnaire included multiple-choice, Likert-scale, and open questions about the demographics, veterinarian-client communication, and euthanasia procedure.

Results: 512 veterinarians completed the survey. Participants indicated that they (almost) always explain the euthanasia procedure to the owner and discuss potential side effects of the medication used. Overall, 93.5% indicated that communication with the owner throughout the procedure is (almost) always easy, and 76.4% indicated that they can (almost) always deal easily with the owner's emotions. Medetomidine and ketamine were most often used to sedate and anesthetize the animal, followed by an IV lethal dose of pentobarbital sodium. The euthanasia procedure was mainly learned from other veterinarians after graduation. Unwanted adverse effects were generally rare, but a painful injection and vomiting were commonly reported as possible side effects. Several veterinarians reported a need for more education.

Conclusions: A wide range of different euthanasia procedures was found, which may be linked to limited education on this subject in the veterinary curriculum.

Clinical relevance: Further in-depth research into the occurrence of adverse events during pet euthanasia is warranted to ensure the well-being of all stakeholders.

Objective: To evaluate the accuracy of recordings of atrial and ventricular depolarizations in 9-lead ECG of cats, with V1 placed at the right first intercostal space at the costochondral junction and V2 and V4 at the fifth or the sixth intercostal space (adjacent to the sternum and at the costochondral junction), and to assess the effect of age-related cardiac positional changes on ECG parameters.

Methods: 60 healthy client-owned cats were planned to be enrolled from January 1, 2024, through December 31, 2024. Each cat underwent physical examination, thoracic radiography, 9-lead ECG, and echocardiography. Cats were age-grouped (< 5, 5 to 10, and > 10 years). The radiographic heart-sternum angle (HSA) in right lateral view was measured and correlated with ECG findings.

Results: The V1 location enabled recording of negative P waves and QRS complexes with R/S ≤ 1, with significant intergroup differences (0.68 ms [IQR, 0.42], 0.37 ms [IQR, 0.32 ms], and 0.48 ms [IQR, 0.65 ms]; P = .04). In V2 and V4 in both sites, P waves were predominantly positive, and QRS complexes showed R/S > 1, with minimal intergroup differences. Aging was associated with a significant HSA reduction (r = -0.72) but did not affect any clinically relevant ECG variables.

Conclusions: This 9-lead system, with V1, V2, and V4 positioned as in dogs, enabled accurate P waves and QRS recording in cats. Aging reduced HSA without major effects on wave morphology.

Clinical relevance: This system will support detailed arrhythmias analysis in feline patients.

Objective: To investigate factors influencing pulsed-wave Doppler transmitral flow profiles and evaluate their diagnostic value in dogs with myxomatous mitral valve disease (MMVD).

Methods: Dogs with MMVD underwent echocardiography; thoracic radiography; blood analysis, including N-terminal pro-B-type natriuretic peptide; and clinical staging. Dogs were divided into mitral E/A peak (E/A) reversal and no reversal groups. Correlations of E-wave velocity (E-vel) and peak velocity (P-vel; higher of E or A wave) with MMVD indices were analyzed, and receiver operating characteristic curves assessed diagnostic performance.

Results: Of 61 dogs, 25 dogs were assigned to the no reversal group and 36 to the reversal group. No significant differences were identified between the groups in most variables. E-wave velocity correlated strongly with left ventricular dilation indices (vertebral heart size, left ventricular end-diastolic diameter in diastole normalized for body weight), whereas P-vel correlated more with left atrial (LA) enlargement indices (vertebral LA size, LA-to-aorta ratio, LA fractional shortening) and N-terminal pro-B-type natriuretic peptide. Peak velocity also showed closer association with International Small Animal Cardiac Health Council class than E-vel. Receiver operating characteristic analysis demonstrated E-vel effectively identified LV dilation, whereas P-vel was superior for detecting LA enlargement.

Conclusions: E-vel may reflect LV dilation, whereas P-vel better may represent LA enlargement and functional burden, particularly in dogs with altered transmitral flow profiles.

Clinical relevance: Incorporating both E-vel and P-vel provides a more comprehensive assessment of cardiac remodeling in MMVD, supporting improved staging and monitoring in clinical practice.

Objective: To train a deep learning-based markerless gait analysis model from random initialization, tailored for canine gait analysis, in clinical settings and to validate against 2-D marker-based systems.

Methods: This prospective observational study used 408 client-owned dogs of more than 30 breeds, ranging from small to large body types. Dogs walked or trotted a 3.3-m straight walkway and were recorded via a lateral single-camera setup using a smartphone camera (1080p resolution, 30 frames/s). Of these, 374 dogs contributed 20,000 markerless images for model training. For model validation and testing, 34 dogs (20 for the validation set and 14 for the test set) were recorded with physical markers that were directly attached to specific bony landmarks by a veterinarian to generate ground-truth data, and each subset included 10 breeds representing a range of sizes and morphologies. The ViTPose-L model was further trained from random initialization on the canine-specific dataset. Accuracy was evaluated using the Common Objects in Context (COCO)-style mean average precision, normalized keypoint error, and percentage of correct keypoints.

Results: The markerless model achieved high accuracy, with a mean average precision of 96.6%, mean normalized keypoint error of 2.29 and percentage of correct keypoints at 0.05 of 92.62%. The model's performance exceeded previously reported benchmarks on public datasets.

Conclusions: A deep learning-based markerless gait analysis system shows promising but early-stage accuracy for canine landmark localization compared with 2-D marker-based data.

Clinical relevance: This system may offer clinical utility for canine gait assessment, but further validation across breeds and environments is needed before routine use.

Objective: To report the radiographic quadriceps angle (Q-angle) in a cat population and to determine the repeatability and reproducibility of the method of measurement.

Methods: A population of client-owned cats presented to a single referral center from October 2024 through April 2025 was submitted to a radiographic study. Cats anesthetized for any procedure and free of orthopedic and neurologic conditions affecting the hind limbs were included. Orthopedic Foundation for Animals guidelines were used for positioning. Radiographs were reviewed, and the Q-angle was calculated. The repeatability and reproducibility of the method were subsequently determined.

Results: 27 cats were included for radiographic study. The mean Q-angle was 15.7 ± 1.1° (95% CI, 12.6° to 18.7°). There was no significant correlation between the Q-angle value and the age, sex, or breed of cats. The intraclass correlation coefficient for interobserver agreement was 0.63. Intraclass correlation coefficients for intraobserver agreement were 0.90, 0.88, and 0.94.

Conclusions: The mean radiographic Q-angle in this cat population was 15.7 ± 1.1° (95% CI, 12.6° to 18.7°). Inter- and intraobserver agreement evaluations were consistent, with moderate reproducibility and good to excellent repeatability of the method of measurement.

Clinical relevance: To our knowledge, this is the first study reporting the radiographic Q-angle in a population of cats. It can be used as a supplementary tool for anatomic evaluation. Further studies are needed to determine its usefulness, especially in the planning of corrective surgeries.

Objective: To characterize the distribution and genetic location of antimicrobial resistance genes (ARGs) in Escherichia coli isolated from pig slaughterhouses in Banten Province, Indonesia.

Methods: 20 E coli isolates were collected from effluent and floor swabs in 10 slaughterhouses. Whole-genome sequencing was performed using Oxford Nanopore technology. Antimicrobial resistance genes were identified using AMRFinderPlus, and plasmid replicons were detected with PlasmidFinder.

Results: ARGs representing 12 antibiotic classes were detected, including aminoglycosides, β-lactamases, colistin, fosfomycin, macrolides, phenicols, quinolones, sulfonamides, tetracyclines, and trimethoprim. Floor isolates carried 28 ARGs, whereas effluent isolates carried 23. β-Lactamase genes showed the greatest diversity (11 types), dominated by blaEC. Many ARGs were plasmid-borne, and 65% of isolates exhibited multidrug resistance potential.

Conclusions: Pig slaughterhouse E coli harbor diverse, plasmid-associated ARGs, indicating active dissemination potential and emphasizing the importance of genomic surveillance.

Clinical relevance: Although this study did not involve clinical patients, the findings are highly relevant to veterinary and public health practice. The detection of diverse, plasmid-associated ARGs in slaughterhouse E coli highlights the need for antimicrobial stewardship and biosecurity measures in pig production systems to mitigate transmission risks to animals, workers, and consumers.