Table of Contents and Abstracts

This report describes 2 spayed female dogs, aged 3 and 14 y, that were presented for chronic, nonhealing wounds after a dog bite and mass removal, respectively. Each case was initially managed on systemic antibiotics and prednisone before referral due to chronic, nonhealing wounds. Fungal cultures were negative for growth, and pythium serology was negative. Computed tomographic imaging of the head, neck, and chest was performed in each case to determine extent of disease and guide surgical debridement. Definitive diagnosis was made by mycobacterial culture, revealing growth of Mycobacterium abscessus. Both dogs were treated with a combination of radical surgical excision and open-wound management, topical amikacin, and systemic antibiotics, including clarithromycin, based on susceptibility testing. These cases demonstrated the diagnostic challenges, utility of surgical excision and open-wound management, and necessity of multidrug therapeutic approaches related to treating M. abscessus in dogs. To the authors’ knowledge, this is the first report of successful treatment of M. abscessus in dogs and may help guide future treatment and clinical awareness of mycobacterial disease in dogs.

Key clinical message:
Mycobacterium abscessus is a multiresistant bacterium complex with emerging incidence worldwide; multimodal treatment, including systemic multidrug therapy and radical surgical excision or debridement, should be considered for management. These cases highlight the importance of a thorough diagnostic workup, open-wound management, and long-term, multidrug antimicrobial therapy as key components of successful treatment.

A 5-year-old spayed female domestic shorthair cat was referred to the Clinical Nutrition Service at the Ontario Veterinary College (Guelph, Ontario) for management of chronic, nonresponsive enteropathy and recently diagnosed diabetes mellitus. The cat was presented with persistent diarrhea, perianal ulceration, weight loss, and poor glycemic control despite treatment with prednisolone, cobalamin injections, a hydrolyzed diet, and short antimicrobial trials. Once hospitalized, the cat was transitioned to a high-protein, low-carbohydrate commercial veterinary therapeutic diet containing mixed protein sources. Nutritional support was initiated via a nasogastric tube but discontinued after 48 h when voluntary oral intake resumed. Clinical signs improved gradually over 5 d, blood glucose stabilized below the renal threshold, and insulin therapy was discontinued at discharge after 6 d of hospitalization. The commercial veterinary therapeutic diet was maintained, and psyllium husk was later added to improve stool quality. Soft stools persisted for several months, with normalization occurring only after targeted fiber supplementation was introduced alongside ongoing medical management. This case highlights the importance of individualized nutritional management in chronic enteropathy, as clinical response to dietary intervention may evolve over time and long-term stabilization may require alternative strategies beyond hydrolyzed-protein diets.

Key clinical message:
Dietary responsiveness in feline chronic enteropathy is highly individualized. Hydrolyzed-protein diets are commonly recommended, but responses may vary between cases. Sequential and sustained dietary trials, guided by clinical response, may be necessary to achieve durable remission.

A 2-month-old Boer doeling weighing 13 kg that was intended for show and breeding was evaluated because of a 2-week history of right hind-limb lameness following suspected trauma sustained during an exhibition. Physical examination revealed a grade 4/5 lameness, stifle instability, and abnormal reciprocal apparatus function consistent with peroneus tertius (PT) rupture. Radiographs showed soft-tissue swelling without fracture. Ultrasonography identified synovial proliferation and a defect at the origin of the PT tendon compared with the contralateral limb. Synovial fluid analysis supported a traumatic inflammatory process. A diagnosis of PT tendon rupture with mild stifle sprain was made, and conservative management, including nonsteroidal anti-inflammatory therapy, antimicrobial administration, stall rest, and physical therapy, was initiated.

The doeling was re-presented 2 wk later with worsening hind-limb lameness, new forelimb lameness, joint effusion, and respiratory abnormalities. Ultrasonography demonstrated abnormal joint effusion and diffuse pulmonary artifacts with mild pleural effusion. Arthrocentesis of the stifle and glenohumeral joints confirmed septic arthritis affecting multiple joints, suspected to be a result of hematogenous spread secondary to bronchopneumonia. Due to a poor prognosis for long-term soundness and productivity, euthanasia was elected.

Key clinical message:
This case documents an uncommon PT rupture in a goat and highlights the diagnostic value of ultrasonography, the risk of systemic disease complicating orthopedic injury, and the need for further characterization of prognosis and management of tendon injuries in small ruminants.

A 1-year-old Maine coon cat was presented with acute onset of central vestibular syndrome and recurrent generalized tonic-clonic seizures. Computed tomographic imaging of the head revealed a left-sided intracranial lesion consistent with an abscess, associated with bilateral otitis media/interna, with more severe involvement of the left tympanic bulla. Based on clinical and imaging findings, the cat underwent surgical intervention consisting of a left temporal burr-hole craniotomy for abscess drainage combined with a unilateral ventral bulla osteotomy. Purulent material was collected during surgery and submitted for bacterial culture, which yielded Staphylococcus aureus sensitive to amoxicillin-clavulanic acid and metronidazole. Postoperative management included intravenous antimicrobial therapy followed by oral treatment after discharge. Transient vestibular dysfunction and Horner’s syndrome were observed after surgery and resolved completely within 3 mo. At a long-term follow-up, the cat was neurologically normal. This case highlights the successful surgical management of an otogenic intracranial abscess in a cat and supports unilateral surgical treatment guided by clinical and imaging findings.

Key clinical message:
Intracranial abscesses secondary to otogenic infection should be considered in cats that have central vestibular clinical signs and seizures. A combined surgical approach using burr-hole craniotomy and ventral bulla osteotomy, guided by imaging findings, can result in favorable clinical outcomes.

Objective
The objective of this study was to evaluate whether diagnostic interval is associated with tumor stage in dogs with malignant nasal tumors and whether intranasal bacterial infection contributes to delayed diagnosis.

Animals and procedure
Medical records of 96 dogs with histopathologically confirmed malignant nasal tumors were retrospectively reviewed. Data included diagnostic interval, clinical stage, results of intranasal bacterial culture, and prior antimicrobial administration. Associations were analyzed using non-parametric tests.

Results
The median diagnostic interval was 83 d (range: 8 to 995 d). Dogs with Stage I tumors had a significantly shorter diagnostic interval than those with Stages II to IV disease (50.0 versus 89.5 d; P = 0.022). When stratified by the overall median interval (≤ 83 versus > 83 d), advanced-stage tumors (Stages III to IV) were more common in dogs with longer intervals (P = 0.014). Bacterial culture was positive in 33 of 57 tested dogs and was not associated with diagnostic interval or tumor stage. Prior antimicrobial therapy (62.5%) was not associated with stage or culture status.

Conclusion and clinical relevance
A longer diagnostic interval was associated with more advanced tumor stage. Intranasal bacterial infection did not explain delayed diagnosis. Persistent nasal signs should prompt further diagnostic evaluation to determine the underlying cause, including neoplasia.

Objective
Our objective was to identify factors associated with the occurrence of surgical wound complications in dogs and cats undergoing soft tissue surgeries; particularly, intraoperative fluid administration and postoperative body weight changes.

Animals and procedure
Forty-seven client-owned animals (35 dogs, 12 cats) underwent laparotomy, thoracotomy, or other soft tissue procedures with skin incisions at the Okayama University of Science Veterinary Medical Teaching Hospital (Imabari, Japan) (2021 to 2024). All surgeries were conducted by the same veterinarian specializing in soft tissue surgery. Surgical wound complications were defined as inflammation, infection, or suture-associated granuloma. Variables assessed included duration of anesthesia, intraoperative fluid administration, and changes in body weight between the preoperative period and postoperative Day 1. Statistical significance was defined as P < 0.05.

Results
Complications occurred in 21 of 47 animals (44.7%). Median duration of anesthesia was significantly longer in animals with complications compared to those without. Intraoperative fluid administration did not differ significantly between groups. However, postoperative body weight increase was significantly associated with the occurrence of wound complications, with multivariate analysis identifying body weight increase as a significant, associated factor (odds ratio: 1.31, 95% CI: 1.02 to 1.69). The incidence of wound complications showed a significant increase in relation to postoperative body weight increase (P = 0.0315).

Conclusion
Increased postoperative body weight, but not intraoperative fluid administration, was associated with the occurrence of surgical wound complications. Prolonged duration of anesthesia was also correlated with complication risk.

Clinical relevance
Monitoring postoperative body weight may serve as a simple and practical method to predict wound complications after soft tissue surgery in dogs and cats. Prospective studies with larger cohorts are warranted to confirm these findings.

Background
Natural bobtail phenotypes, mostly caused by a mutation in the T-box transcription factor T-gene, occur in several dog breeds. Although generally considered benign, reduced tail length may co-occur with structural changes in the lumbosacral spine, raising potential welfare concerns.

Objective
The objective of this study was to investigate whether natural bobtail phenotypes (short- and stump-tails) are associated with the occurrence of lumbosacral transitional vertebra (LTV) in Brittany dogs and Danish-Swedish Farmdogs.

Animals and procedures
This retrospective, cross-sectional study included 1679 dogs [Brittany dogs (n = 744); Danish-Swedish Farmdogs (n = 935)] screened through the Norwegian Kennel Club’s hip dysplasia program. Standardized ventrodorsal pelvic radiographs were evaluated for LTV and tail phenotypes. Associations were assessed using chi-square tests, odds ratios (OR) with 95% confidence intervals (CI), and post-hoc standardized residuals. Tail phenotypes were analyzed as a binary variable (bobtail versus normal) in both breeds and as a 3-category variable (stump, short, normal) in Brittany dogs.

Results
Lumbosacral transitional vertebra prevalence was 47.8% in Brittany dogs and 14.9% in Danish-Swedish Farmdogs, whereas the natural bobtail phenotype (stump + short) occurred in 26.7% of Brittany dogs and 11.0% (short) of Danish-Swedish Farmdogs. In Brittany dogs, bobtailed dogs had significantly increased odds of being LTV-positive compared with dogs having a tail of normal length (OR = 2.04, 95% CI: 1.47 to 2.85; P < 0.001), with the strongest association observed in stump-tailed individuals. In Danish-Swedish Farmdogs, the association was weaker and did not reach statistical significance (OR = 1.66, 95% CI: 0.99 to 2.76; P = 0.05).

Conclusions and clinical relevance
Natural bobtail phenotypes are associated with LTV in Brittany dogs, with stump-tailed dogs showing the strongest association. A similar, non-significant trend was observed in Danish-Swedish Farmdogs.

Background and objectives
Septic arthritis is a common cause of lameness in calves and may be linked to radiographic signs of bone involvement, traditionally considered a poor prognostic factor. The aims of this retrospective study were to identify clinical and treatment-related factors that affected survival in calves with septic arthritis and to determine whether radiographic bone involvement adversely affected outcome.

Animals and procedure
Medical records of 46 calves diagnosed with septic arthritis were reviewed. Data collected included signalment, clinical findings, synovial fluid analysis, radiography, antimicrobial use, and treatment interventions. Calves were categorized as either euthanized at admission or treated in the hospital. Survival and prognostic factors were evaluated in treated calves (n = 29).

Results
Radiographic bone involvement was identified in 22/29 treated calves (76%) and was not associated with decreased survival. Synovial fluid total protein and total nucleated cell count were numerically higher in calves with bone involvement but were not significantly associated with outcome. However, increasing treatment score, reflecting cumulative treatment intensity, was associated with improved survival (OR = 2.42; P = 0.014). In addition, repeated joint lavage was also associated with increased survival, whereas single interventions were not. Prior antimicrobial use on the farm did not significantly influence outcome.

Conclusion and clinical relevance
We inferred that radiographic bone involvement should not be considered an automatic negative prognostic factor in calves with septic arthritis. However, the retrospective design and relatively small sample size of this study limited the strength of these conclusions. Instead, treatment intensity and a multimodal therapeutic approach appeared to have a more important role in determining outcome.

Objectives
The objectives of this work were to assess if the Western Canadian Animal Health Network (WeCAHN) has been able to leverage existing data sources to provide actionable intelligence to stakeholders over the initial 5 y, and to identify potential method enhancements or directions for future surveillance activities.

Animals and procedure
This work involved beef and dairy cattle, sheep and goats, poultry, and horses. Quarterly clinical impressions surveys completed by veterinary practitioners and anonymized diagnostic laboratory data were the primary data sources used to detect signals in selected examples of 3 WeCAHN surveillance goals: i) support for the demonstration of freedom from disease, ii) identification of trends in prioritized production-limiting diseases, and iii) recognition of emerging syndromes. Data interpretation was enhanced through network discussions among veterinarians, diagnosticians, and stakeholders.

Results
Integrating veterinary practitioner observations with laboratory data consistently supported early recognition and validation of potential animal health surveillance signals. No signals of vesicular disease compatible with foot and mouth disease were detected, and practitioner surveys documented ongoing client-awareness discussions. Increasing Johne’s disease detections were identified in both practitioner surveys and laboratory data, prompting collaboration with industry stakeholders on targeted knowledge translation activities. A new syndrome of neonatal hepatic necrosis in beef calves was identified. A case definition was drafted, and recommended regional diagnostic guidelines were shared.

Conclusion and clinical relevance
Assessment of WeCAHN’s data synthesis demonstrated that combining practitioner, laboratory, and discussion-based interpretation effectively converted large, heterogeneous datasets into actionable regional animal health intelligence. These collaborative methods offer a foundation for enhanced future surveillance and signal detection across western Canada.

A 3-year-old Holstein cow was presented with generalized cutaneous plaques and nodules after receiving topical eprinomectin at 136 days in milk. The cow’s health was otherwise normal, she was seronegative for bovine leukemia virus, and her lesions regressed by 200 days in milk. The cutaneous form of sporadic bovine T-cell leukosis was diagnosed.

Key clinical message:
This report describes a case of sporadic bovine cutaneous T-cell lymphosarcoma.