Table of Contents and Abstracts

A 10-month-old male castrated beagle dog, without prior history of ocular disease, was referred for a corneal mass of the right eye. A non-painful raised mass with frond-like projections originated from the dorsotemporal paraxial cornea of the right eye. In addition, a plaque-like conjunctival lesion and several raised, smooth masses of the eyelid were noted around the right eye. An incisional biopsy of the corneal mass and an excisional biopsy of the conjunctival mass were performed. Histopathology confirmed the clinical diagnosis of viral papilloma. Conservative management with monitoring was elected, and the lesion self-resolved 3 mo after initial appearance.

Key clinical message:
This case suggests that monitoring is appropriate for corneal lesions definitively diagnosed as viral papillomas, as they may be self-limiting.

Within 16 d, a small farrow-to-finish operation and 2 sow herds broke with the same strain of porcine reproductive and respiratory syndrome (PRRS) virus. Although no certainty could be obtained, based on the epidemiological investigation that was undertaken, we inferred that the most plausible source of contamination was aerosol, over a distance of at least 6.1 km.

A 13-year-old spayed female Labrador retriever cross dog was referred to the Foster Hospital for Small Animals at Tufts University for evaluation of a metastatic carcinoma discovered at the site of a previous tibial plateau leveling osteotomy (TPLO). The dog was previously evaluated at the primary care veterinarian for a complaint of lameness, and radiographs of the previous TPLO site revealed bony lysis associated with the TPLO plate. Surgical exploration of the site by the primary veterinarian provided evidence of osteolysis. The lytic area of the proximal tibia was biopsied, and a metastatic carcinoma was confirmed. The patient was referred for further evaluation. Following consultation and examination, a full body computed tomography (CT) scan was performed to determine the source of the carcinoma. A well-defined soft tissue attenuating mass effacing the right thyroid gland was located, along with 3, well-defined soft tissue attenuating nodules within the pulmonary parenchyma, consistent with metastatic disease. The previously diagnosed osteolytic, aggressive bone lesion of the proximal left tibia was visualized. Following the CT scan, palliative left hind-limb amputation via coxofemoral disarticulation was performed. Histological examination of the hind limb revealed neoplastic epithelial cells admixed with reactive bone. Neoplastic cells were arranged in packets with rare colloid-filled microfollicles consistent with a diagnosis of metastatic thyroid carcinoma. To the authors’ knowledge, this is the first clinical report of metastatic thyroid carcinoma in the appendicular skeleton and TPLO site of a dog.

Key clinical message:
Our findings emphasized that thyroid carcinoma may metastasize to the appendicular skeleton, and causes other than osteomyelitis or implant-associated osteosarcoma should be considered when evaluating osteolytic lesions at a TPLO site.

The techniques and clinical outcomes of laparoscopic or laparoscopic-assisted cystopexy in 3 dogs diagnosed with pelvic bladder are reported herein.

The medical records of 2 dogs with pelvic bladder which underwent laparoscopic cystopexy, and 1 dog which underwent laparoscopic-assisted cystopexy were reviewed. Data retrieved included signalment, clinical signs, diagnostic imaging, surgical technique, and clinical outcome. Long-term follow-up was obtained by verbal interviews with owners.

Laparoscopic or laparoscopic-assisted cystopexy was successfully performed to reposition the urinary bladder within the abdominal cavity in all dogs. An intracorporeal suture technique was used in 2 dogs, whereas an extracorpreal technique was used in 1 dog. Two dogs with stranguria experienced complete resolution immediately following surgery and remained disease-free at 18 mo after cystopexy. A third dog with urinary incontinence subjectively improved (according to the owner) but had not resolved completely 2 d following surgery.

Key clinical message:
Laparoscopic or laparoscopic-assisted cystopexy may be an effective treatment for pelvic bladder in dogs and may offer a minimally invasive alternative to laparotomy. Male dogs with stranguria as the primary clinical sign may experience complete resolution following cystopexy.

Objective
The objective of this report is to describe the technique and diagnostic utility of indirect lymphography (IL) using water-soluble contrast for sentinel lymph node (SLN) mapping in dogs with mast cell tumors.

Animals
Fifty-three dogs with 59 mast cell tumors were included.

Procedure
Medical records were retrieved for dogs with a cytological diagnosis of mast cell tumor which also had IL performed for lymph node mapping. Dogs were excluded when surgery had been performed before presentation. Images were reviewed by a Board-certified radiologist for uptake of contrast within the sentinel lymph node.

Results
Lymphography studies from 34 tumors (57.6%) were diagnostic (clearly identifiable lymphatics and sentinel lymph node). Lymphography studies from 12 tumors (20.3%) were partially diagnostic (identifiable lymphatics, but sentinel lymph node not highlighted). Lymphography studies from 13 tumors (22%) were non-diagnostic. Indirect lymphography studies were interpreted as either diagnostic or partially diagnostic in 77.9% of tumors.

Conclusion
The results indicate that IL is a simple, available technique to allow for identification of a sentinel lymph node in dogs with mast cell tumors.

Clinical relevance
Indirect lymphography is a simple and widely accessible technique for SLN mapping in dogs with mast cell tumors, particularly for the general practice environment.

Data on dogs and cats that underwent surgery for a traumatic diaphragmatic hernia were retrospectively collected and analyzed, with an objective to identify factors that influenced the survival rate. Forty-nine dogs and 48 cats were included. The predominant respiratory clinical sign was dyspnea, and the interval from trauma to development of clinical signs did not influence patient survival. Concurrent orthopedic and/or soft tissue injuries were identified in 48.45% of the animals. Intraoperative complications occurred in 14 dogs and 5 cats, and postoperative complications in 7 dogs and 6 cats. Intraoperative death occurred in 6.2% and postoperative death in 8.3% from 1 h to 10 d after surgery. Animals that received surgical treatment within 48 h after diagnosis had a lower risk of death. Conversely, concurrent injuries and intraoperative and postoperative complications were the main factors associated with a higher risk of death.

Objective
To retrospectively evaluate complication rates following bilateral tibial plateau leveling osteotomy (TPLO) as well as owner assessment of outcomes and post-operative management.

Methods
Medical records of dogs presenting with bilateral cranial cruciate ligament (CCL) disease that underwent single-session bilateral TPLO from 2015 to 2019 in 1 referral practice were retrospectively reviewed. A non-validated questionnaire was sent to the owners to assess their ability to cope during the rehabilitation period, as well as procedure outcome.

Results
In total, 127 dogs were included for analysis. The overall complication rate was 16.5% (minor complication rate 9.4% and major complication rate 10.2%). Of the 50 owners that answered the questionnaire, 31 (62%) did not need to use sling support at home at any time and 10 (20%) used sling support for < 1 wk. Furthermore, only 1 owner indicated that they would not choose to do a bilateral TPLO surgery again.

Clinical significance
Bilateral single-session TPLO surgery performed by an experienced surgeon had a similar outcome and complication rate to that of unilateral TPLO surgery. Most owners reported that postoperative care of their dog was not difficult.

Background
In both human and veterinary medicine, it is recommended that an anesthetic machine checkout procedure (pre-use check) be performed daily, with some items tested before each case, to confirm safe function and the check results recorded.

Objective
The objective of this prospective study was to evaluate anesthetic machines in private veterinary clinics in Alberta (Canada) using a standardized checkout procedure.

Animals and procedures
One-hundred consecutive anesthetic machines were assessed. For each item of the checkout procedure, a “pass,” “fail,” or “not applicable” score was awarded. “Not applicable” indicated an item that could not be evaluated.

Results
Few machines (10%) evaluated had a secondary oxygen supply, no machines had an oxygen supply pressure alarm, and leaks were identified in 31 and 17% of rebreathing and non-rebreathing systems, respectively. Thirty-nine percent of machines did not have a high-pressure circuit alarm, 86% of machines were attached to an active scavenging system, although it was improperly connected in 56% of cases, and only 2% of machines were accompanied by a checkout log.

Conclusion and clinical relevance
There was widespread variation in anesthetic machine standards and function, highlighting the value of performing a regular machine checkout procedure in creating a foundation for safe anesthetic practice.

Objective
Risk factors for the development of canine appendicular osteosarcoma (OSA) have been investigated in numerous studies, but with contradictory results. The aim of this study was to analyze weight, age, breed, sex, neuter status, body condition score, and previous lameness in a population of large and giant breed dogs in western Canada with and without appendicular OSA.

Animals and procedure
Medical records of 227 large or giant breed dogs diagnosed with appendicular OSA were compared to records from a control population of 454 large and giant breed dogs from the years 2000 to 2020.

Results
Gonadectomized dogs, body condition score (BCS), and a history of lameness condition(s) (other than OSA) were associated with increased odds for presentation with OSA. Breeds shown to have increased odds for appendicular OSA occurrence included Rottweilers and Great Danes relative to Labrador retrievers.

Conclusion and clinical relevance
Obesity and lameness appear to be independently associated with appendicular osteosarcoma. This study demonstrated that spayed females had the greatest risk compared to other sex and neuter status combinations; further investigation of these factors would be beneficial.

Objectives
The primary goals of this retrospective study were to describe a population of dogs with portal hypertension secondary to liver disease, and to assess whether prognosis could be inferred from historical, clinical, and clinicopathological data.

Animals and procedures
Dogs (N = 76) diagnosed with intrahepatic portal hypertension between 2011 and 2020 were included; dogs with known congenital hepatic anomalies were excluded. Effect on survival was assessed using univariable and multivariable Cox proportional hazards models for historical, clinical, and clinicopathological variables.

Results
Dogs survived for a median of 14 d (range: 0 to 2028 d), with 31.6% being euthanized within 2 d of diagnosis and 23.7% surviving longer than 2 mo. Presence of jaundice and duration of clinical signs, expressed in days, were significantly associated with outcome in the univariable analysis (HR = 1.846, 95% CI: 1.094 to 3.117, P = 0.02; HR = 0.995, 95% CI: 0.990 to 1.000, P = 0.033, respectively). However, only presence of jaundice was significantly associated with increased hazard of death in the multivariable analysis.

Conclusion
Results of this study show that portal hypertension is associated with a poor prognosis; however, some dogs can show prolonged survival.

Clinical relevance
Clinical data can guide decision-making for clinicians and owners.

Over a 5-month period, 7 Holstein heifer calves on a farm in Drumbo, Ontario were discovered to have bilateral cataracts, 5 of which were considered acquired (versus congenital). Although the inciting cause remains unknown, extensive testing ruled out several possible causes, including bovine viral diarrhea virus (BVDV), Mycoplasma bovis, and Leptospira sp. infection, and nutritional factors.