Table of Contents and Abstracts

A 4-year-old intact female dachshund dog was presented in shock after a traumatic event. The dog had sustained hemoperitoneum and pulmonary contusions. Veterinary point-of-care ultrasound revealed reverberation artifacts inside the liver. Abdominal ultrasonography and computed tomography identified these as lesions of hepatic emphysema. Biochemical analysis showed marked elevation of liver enzymes. Treatments included S-adenosylmethionine and broad-spectrum antibiotics, among others. Two weeks following trauma, alanine aminotransferase was near normal and there was almost complete resolution of the hepatic lesions on abdominal ultrasonography. This case report is the first to describe the medical management and time course of parenchymal hepatic emphysema in a dog following trauma. It also focuses on the diagnosis of hepatic emphysema using various imaging modalities.

Key clinical message:
Hepatic parenchyma emphysema can develop following blunt abdominal trauma and appears as bright, hyperechoic foci with reverberation artifacts that can be easily observed with veterinary point-of-care ultrasonography or complete abdominal ultrasonography. Hepatic emphysema does not always require surgical treatment. Monitoring biochemical abnormalities and lesions with various imaging modalities, along with providing supportive treatments, can sometimes be sufficient.

Half of all epilepsy cases in both humans and canines are identified as idiopathic. Of these cases, 30 to 40% remain treatment-refractory to antiepileptic medications. Several human and dog studies have demonstrated low-carbohydrate diets and dietary medium-chain triglyceride (MCT) supplementation are effective for seizure reduction, with some patients achieving a seizure-free status. Recent evidence suggests the gut-brain axis has an important role in the pathology of neurological disease among both humans and dogs. Altered gut microbiota may have a major role in treatment-refractory epilepsy. This case report describes a dog with treatment-refractory epilepsy experiencing cluster seizures triggered by an altered gut microbiome despite therapeutic drug concentrations of multiple agents. Consideration of an underlying gastrointestinal disorder should be investigated in patients with treatment-refractory epilepsy, despite therapeutic concentrations of several antiepileptic medications. Dietary and gastrointestinal health-promoting interventions for epilepsy should also be considered before add-on pharmacotherapy or euthanasia. For difficult epilepsy cases, we suggest exploring the role of a limited-ingredient, low-carbohydrate diet, MCT supplementation, and/or pre/probiotics to augment pharmacotherapeutic strategies. This information may be critically valuable in designing high-quality, diet-based therapies for epileptic dogs.

Key clinical message:
Gastrointestinal workup, dietary changes to a low-carbohydrate diet, supplementation with MCTs, and addition of pre/probiotics could be considered to augment pharmacotherapeutic strategies in treatment-refractory epilepsy cases in dogs.

A 1-year-old intact male American pit bull experienced a ruptured right femoral artery without trauma or coagulopathy. The dog was presented with right pelvic limb lameness and progressive subcutaneous swelling and bruising. Radiographs of the region identified soft-tissue swelling in the right thigh musculature. Bloodwork monitoring consisted of packed cell volume and total solids, which continued to decrease during hospitalization. A CT scan showed a non-contrast-enhancing possible mass effect in the region. Multiple blood and plasma transfusions were instituted while the dog was in hospital and in preparation for amputation of the limb due to concern for a neoplastic process. During surgery, upon removal of a blood clot, profuse hemorrhage from a branch of the femoral artery was noted. The artery was ligated and amputation completed without complication. After surgery, the packed cell volume returned to normal and no additional bruising was noted. Histopathologic examination of the amputated limb showed extensive subacute hemorrhage and hematoma formation. No evidence of neoplasia or inflammatory foci was noted. At a 2-week recheck, all bruising had resolved and the dog was walking well.

Key clinical message:
This case report describes the first diagnosis and treatment of a suspected spontaneous femoral artery rupture in veterinary medicine.

A 3-year-old female dromedary camel was referred as an urgent case for evaluation of chronic weight loss, facial deformity, and hind-limb lameness. On initial examination, the camel was emaciated, with bilateral masses protruding from the maxillary and mandibular bones and extending into the oral cavity; the lameness could not be assessed due to recumbency. Clinical pathology and fecal flotation findings were consistent with secondary nutritional hyperparathyroidism, hypovitaminosis D, marked anemia, hypoproteinemia, and parasitism. The camel was euthanized based on the presumptive diagnosis of fibrous osteodystrophy, which was confirmed on postmortem examination. Preventative strategies were recommended for future care of dromedaries and included camel husbandry with adequate ultraviolet light exposure, adequate nutrition, appropriate anthelmintic control programs, and vitamin D supplementation.

Key clinical message:
The cause of fibrous osteodystrophy in camels can be multifactorial and include secondary nutritional hyperparathyroidism, hypovitaminosis D due to inadequate exposure to ultraviolet light or intake, and parasitism. Specific nutrient requirements, sun exposure, and anthelmintic protocols are essential for camels living in North America.

A 2-year-old male Abyssinian cat was presented with a left head tilt, lethargy, compulsive walking with a left-circling tendency, medial strabismus, a delayed pupillary light reflex, abdominal papules, and severe pruritus that began at 4 mo of age. Imaging revealed mineral opacity foci in the left ear, and magnetic resonance imaging confirmed heterogeneous signal changes, suggesting a diagnosis of otitis interna. No abnormal findings were observed on cerebrospinal fluid tests. Treatment with prednisolone, antibiotics, a hypoallergenic diet, and probiotics led to the resolution of skin issues and neurological improvement. Despite a persistent head tilt after more than 5 mo, there was no recurrence of severe neurological symptoms during the tapering off of prednisolone treatment.

Key clinical message:
This is the first case report illustrating the potential impact of feline atopic syndrome on the central nervous system. It emphasizes the importance of viewing feline atopic syndrome as more than just a skin disorder.

This report describes the case of a 5-year-old spayed female munchkin cat that was presented with respiratory distress. Thoracic radiography revealed pleural effusion with a diffuse interstitial lung pattern. Echocardiography identified a mass compressing the left atrium, accompanied by a turbulent jet-like flow from the pulmonary veins, with a velocity of 1.6 m/s. Computed tomography revealed a diffuse, homogenous mediastinal mass compressing the dorsal border of the left atrium and surrounding the ascending aorta and the pulmonary arteries and veins. The distal caudal pulmonary veins were dilated, indicating pulmonary vein stenosis secondary to the mediastinal mass. The caudodorsal ostium was stenotic due to the mediastinal mass compression. In addition, bilateral adrenomegaly and multifocal masses were evident in the kidneys, stomach, and cecum. Lymphoma was diagnosed in the cecal mass using cytology and PCR for antigen receptor rearrangements (PARR). This case describes clinically significant acquired pulmonary vein stenosis secondary to a mediastinal mass, which was likely responsible for the respiratory distress and pleural effusion.

Key clinical message:
To our knowledge, this is the first report of acquired pulmonary vein stenosis secondary to a mediastinal mass in a cat. Computed tomography could be helpful in confirming pulmonary vein stenosis and identifying its etiology.

Background
Checklists are widely recognized as safety measures in both aviation and human medicine, effectively preventing omissions caused by memory failures.

Objective
To assess whether a pre-induction safety checklist completed by veterinary students during a spay/neuter laboratory minimized the number of incomplete pre-induction tasks.

Participants and procedure
Third-year veterinary students (N = 53) managed the anesthesia of dogs and cats admitted for spay/neuter surgery under supervision. The use of a pre-induction checklist was mandatory to ensure appropriate preparation before anesthesia induction. Differences in checklist completeness between the 1st and 2nd wk of the spay/neuter laboratory were compared using Fisher’s exact test.

Results
Over 2 wk, 83 anesthesia procedures were completed. Use of the pre-induction checklist identified at least 1 omitted pre-induction task in 67.5% (56/83) of anesthesia procedures. The number of incomplete pre-induction tasks identified through use of the checklist decreased significantly from the 1st (82.9%, 34/41) to the 2nd (52.4%, 22/42) wk (odds ratio: 4.4, 95% CI: 1.7 to 11; P = 0.0046). The most frequently missed item was premeasuring the endotracheal tube insertion depth (42.2%, 35/83), followed by failure to leak-test the endotracheal tube cuffs and not having gauze available (15.7%, 13/83 for each). Finally, the checklist identified closed adjustable pressure-limiting valves in 4.8% (4/83) of cases.

Conclusion and clinical relevance
The pre-induction checklist was effective in ensuring that veterinary students completed relevant pre-induction tasks during a spay/neuter laboratory. Results suggested the pre-induction checklist was a valuable tool that improved patient safety and prevented life-threatening equipment errors such as closed adjustable pressure-limiting valves.

Background
Contact networks influence infectious disease risk and transmission.

Objective
To evaluate dog contact numbers and exposure to higher-risk activities (e.g., day care) in dogs from Canada and the United States.

Animals and procedure
Dog owners were recruited to participate in a survey about their dogs’ contacts with other dogs and participation in selected activities.

Results
Data were obtained for 1058 dogs: 829 from a commercial survey group and 329 from a social media recruitment group. Median numbers of dog contacts in the preceding 24 h, 7 d, and 14 d were 1, 3, and 4, respectively, in the social media group, and 2 for each time period in the commercial survey group. In the commercial survey group, dogs had a median of 1 type of queried contact (e.g., day care) (range: 0 to 10). In the social media group, 16% dogs had no reported contacts with any other dogs in the preceding 24 h, whereas 5.2% had no contacts in the preceding week and 3.0% had no contacts over the preceding 2 wk.

Conclusion and clinical relevance
Dog contact activities are variable and influenced by many factors. Understanding this is important for disease modeling, development of infection-control interventions, and assessment of risk.

Objective and animals

Mycobacterium avium subsp. paratuberculosis (Map) has been identified in a wide range of domestic and wild ruminants. Captive wildlife, including Bison spp., can experience Johne’s disease-related epidemiological scenarios similar to those seen in cattle. To date, there is no epidemiological information about Map in captive wood bison (Bison bison athabascae) herds. The objective of this study was to examine age, sex, and location-specific density as potential risk factors associated with Map positivity in a captive wood bison herd located in Alberta.

Procedure and results
Fecal samplings were obtained from October 2021 to October 2022, DNA was extracted, and qPCR targeting IS900 and F57 followed by liquid culture confirmation was completed. Within-herd prevalence of IS900/F57 qPCR in October 2021 was 4.7%; prevalence of IS900 qPCR with culture confirmation was 6.8%. Regression analysis using 3 different outcomes based on different diagnostic approaches was employed: “base scenario” (positive result by fecal IS900 qPCR with culture confirmation of IS900/F57 qPCR), “scenario 1” (positive result by fecal IS900 qPCR with culture confirmation of IS900 qPCR), and “scenario 2” (positive result by fecal F57 qPCR with culture confirmation of F57 qPCR). Wood bison in the age group ≥ 6 to 9 y were more likely to be Map-positive in all scenarios. Location B (higher animal density) was significantly associated with animals being Map-positive in base scenario and scenario 1.

Conclusion and clinical relevance
This study identified risk factors related to Johne’s disease in a captive wood bison herd. The findings can be used to initiate more studies in both the commercial and wild wood bison herds.

Objective
Antimicrobial resistance is a serious threat in human and veterinary medicine. Among the most problematic resistant organisms are the extended-spectrum β-lactamase (ESBL)-producing Enterobacterales, which are resistant to the 3rd-generation cephalosporins. The purpose of this study was to determine the frequency of colonization of horses admitted to the Western College of Veterinary Medicine with resistant Escherichia coli.

Animals and procedure
Rectal swabs were collected from 60 horses admitted between November 2021 and March 2022. Swabs were selectively cultured for E. coli, which was identified using standard biochemical tests. The antimicrobial susceptibility of isolates was determined, and resistant isolates were screened using PCR for the presence of ESBL.

Results
Escherichia coli was isolated from all 60 horses. Although pansusceptibility was the most commonly identified phenotype, multidrug-resistant isolates possessing a CTX-M-type ESBL were recovered from 1 horse. Resistance to trimethoprim + sulfamethoxazole was the most commonly encountered resistant phenotype.

Conclusion and clinical relevance
Although resistance was uncommon, the identification of ESBL-producing isolates highlighted the importance of continued surveillance to monitor the emergence of resistance in equine populations.

Objective
In light of growing concerns regarding potential increases in porcine circovirus type 2 (PCV2)-associated diseases in Quebec between 2021 and 2022, the objective was to characterize PCV2 genotype diversity in Canada.

Samples and procedure
A total of 54 analyzed samples (2021 to 2023) either were submitted by veterinarians to the Molecular Diagnostic Laboratory (MDL) of the Centre de Diagnostic Vétérinaire de l’Université de Montréal (CDVUM) or were collected from pigs necropsied at the Quebec Ministry of Agriculture, Fishery and Food (MAPAQ) laboratories. The sick pigs from which samples were collected had various clinical signs, including those of PCV2-associated diseases. Whole-genome sequencing for PCV2 was done either by Sanger sequencing from 2 PCR amplicons covering the entire viral genome or by high-throughput sequencing.

Results
The main PCV2 subtype identified as circulating in Canada was PCV2d (48.1%). Only 1 strain clustered into the PCV2e subtype (1.9%). In previous reports, PCV2b was the main subtype present in the field. However, only 5 PCV2b sequences (9.3%) were identified in 2022 and 2023.

Conclusion and clinical relevance
This is apparently the first official identification of PCV2d and 2e genotypes in diseased Canadian pigs. Results also provided an overview of PCV2 strains now circulating in Canada compared to reports from 2007 to 2008.

Background
Salmonella enterica subsp. enterica serovar Dublin (Salmonella Dublin) is a Gram-negative bacterium of increasing importance to the Canadian cattle sector.

Objective, animal, and procedure
The objective of this narrative literature review was to provide an overview of the epidemiology of Salmonella Dublin in cattle, highlight risk factors associated with infection, discuss diagnostic methods, and review prevention and control strategies, with a specific focus on the Canadian context.

Results
Approximately 3 to 30% of dairy farms are positive for Salmonella Dublin, depending on the province. This bacterium can cause high levels of morbidity and mortality and is best controlled by preventing carrier cattle from gaining access to uninfected farms.

Conclusion and clinical relevance
Salmonella Dublin is an emerging pathogen and action is necessary to control its spread.