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Abstract

Objective—To evaluate the outcome of the application of an external skeletal fixator intramedullary pin tie-in (TIF) to tibiotarsal fractures in raptors.

Design—Retrospective case series.

Animals—Thirty-four raptors with 37 tibiotarsal fractures.

Procedures—Medical records and radiographs for raptors with tibiotarsal fractures that were treated at The Raptor Center at the University of Minnesota between 1995 and 2011 were reviewed. Descriptive statistics were generated and univariate logistic regression analyses were used to assess whether age, sex, body weight, location and nature of the fracture, and type of surgical reduction were significantly associated with whether the fracture healed following surgical reduction and TIF application.

Results—31 of 37 (84%) tibiotarsal fractures successfully healed following surgical reduction and TIF application. The mean healing time was 38 days (range, 15 to 70 days). None of the variables assessed were significantly associated with whether the tibiotarsal fracture healed. Twenty of the 34 (59%) raptors were eventually rehabilitated and released.

Conclusions and Clinical Relevance—Results indicated that most tibiotarsal fractures were successfully managed by surgical reduction and stabilization with a TIF. However, other comorbidities (eg, systemic infections and visual deficits) negatively affected the rehabilitation of raptors and sometimes resulted in euthanasia despite the fact that the tibiotarsal fracture had healed, and those comorbidities, along with the variables evaluated (eg, age, sex, and nature of the fracture), should be used as triage criteria and prognostic indicators.

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE

To evaluate the enhancement accuracy of a triple-phase abdominal CT angiography (CTA) protocol in dogs and explore the patient, scan, and contrast parameters associated with accuracy of enhancement.

ANIMALS

233 client-owned dogs that underwent routine abdominal CTA.

PROCEDURES

During each CTA study, the subjective timing accuracy (early, ideal, late) of the 3 obtained vascular phases (arterial, venous, delayed) was scored by consensus (2 reviewers) at 4 target organs (liver, pancreas, left kidney, and spleen). These scores were evaluated for statistical associations with 21 study variables (patient, scan, and contrast medium). The objective enhancement (HU) for each target organ was also compared statistically with subjective timing accuracy scores and the study variables.

RESULTS

The study protocol performed best for the pancreas, moderately for the liver, and worse for the spleen and left kidney. Measurements of scan length and time were associated positively with phase lateness for most target organs and phases. Increased heart rate was the most significant patient factor associated positively with phase lateness within the liver (all phases), pancreas (arterial and venous phases), and kidney (arterial phase). Contrast medium variables were less associated with timing accuracy in this protocol. Objective enhancement (HU) correlated poorly with subjective phase timing accuracy and study variables.

CLINICAL RELEVANCE

Scan time, scan length, and heart rate were the predominant variables contributing to lateness in this canine abdominal CTA protocol. The findings of this exploratory study may aid in protocol adjustment and choice of included anatomy for dogs undergoing routine abdominal CTA.

Open access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To identify physical examination and perioperative CBC variables in dogs with splenic hemangiosarcoma (HSA) that could aid in predicting progression-free interval (PFI) and overall survival time (OST) in affected dogs.

ANIMALS

70 client-owned dogs with splenic HSA treated with splenectomy and chemotherapy between September 2004 and October 2016.

PROCEDURES

A retrospective search of the University of Minnesota Veterinary Medical Center medical records database was performed to identify dogs with splenic HSA treated with splenectomy and with evidence in the medical records of intent to treat with chemotherapy. Data collection included dog signalment and body surface area, results from CBCs performed within 6 days before to 2 days after splenectomy, whether dogs had hemoabdomen or received transfusions, and tumor stage. Hematocrit, WBC count, and platelet count were treated as categorical variables (divided into terciles: above, within, or below reference limits) because of variation among reference intervals for the numerous analyzers used. Associations between variables and PFI or OST were investigated with Cox regression analyses, and hazard ratios (HRs) for a shorter PFI or OST were reported. Population Pearson correlation coefficient (ρ) analysis was performed to identify potential associations between variables of interest.

RESULTS

Stage 3 HSA was identified as a negative prognostic indicator of PFI (HR, 6.6) and OST (HR, 4.5). Perioperative thrombocytopenia was similarly associated with shorter PFI (HR, 2.2) and OST (HR, 2.0). Results for Hct correlated (ρ = 0.58) with those for platelet count, and although our findings did not indicate a notable association between anemia and shorter PFI, such could not be ruled out.

CONCLUSIONS AND CLINICAL RELEVANCE

The prognostic value of thrombocytopenia warrants further substantiation to understand causal and mechanistic connections, and the presence of thrombocytopenia ultimately may prove valuable in guiding treatment recommendations for dogs with splenic HSA.

Full access
in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To evaluate a method for identifying intact and degranulated eosinophils in the small intestine of dogs with inflammatory bowel disease (IBD) by use of a monoclonal antibody (mAb) against eosinophil peroxidase (EPX).

ANIMALS 11 untreated dogs with IBD, 5 dogs with IBD treated with prednisolone, and 8 control dogs with no clinical evidence of gastrointestinal tract disease and no immunosuppressive treatment.

PROCEDURES 4-μm-thick sections of paraffin-embedded tissues from necropsy specimens were immunostained with EPX mAb. Stained intact and degranulated eosinophils in consecutive microscopic fields (400X magnification) of the upper (villus tips) and lower (between the muscularis mucosae and crypts) regions of the lamina propria of the jejunum were manually counted.

RESULTS Compared with control and treated IBD dogs, untreated IBD dogs had a significantly higher number of degranulated eosinophils in the lower region of the lamina propria. However, no significant differences were detected in the number of intact eosinophils in this region among groups. In the upper region of the lamina propria, untreated IBD dogs had a significantly higher number of degranulated and intact eosinophils, compared with control and treated IBD dogs. Number of degranulated and intact eosinophils did not differ significantly between control and treated IBD dogs.

CONCLUSIONS AND CLINICAL RELEVANCE Immunohistologic analysis with EPX mAb yielded prominent granule staining that allowed reliable morphological identification of degranulated and intact eosinophils, which may provide a strategy for quantitative and selective evaluation of eosinophils in gastrointestinal biopsy specimens and a potential method to diagnose IBD and evaluate treatment outcome.

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To explore relationships between 9-axis inertial measurement unit (IMU) output and activities of varying intensity in dogs of various sizes.

ANIMALS

20 healthy, agility course–trained dogs of various ages and sizes.

PROCEDURES

Height, weight, body condition score, age, length from IMU to the ischium, and height of IMU to the floor were recorded. Dogs performed a series of activities (rest, walk, trot, and agility course) while wearing the IMU device. IMU and video output were reviewed by independent investigators. Correlations and multiple regression models were used to explore relationships between independent variables and IMU output.

RESULTS

Calibration demonstrated excellent correlation and concordance between IMUs (intraclass correlation > 0.9) and that the IMUs reliably measured a known acceleration (gravity at rest). Resultant vector magnitude {sqrt[(x^2) + (y^2) + (z^2)]} normalized to body size was calculated from the data. IMU output clearly discriminates between activities of varying intensity in the dog.

CLINICAL RELEVANCE

The inability to accurately measure chronic pain is a barrier to the development of new, or critical evaluation of, therapeutics. Activity monitors (AM) may be the ideal diagnostic target since they are small and provide objective data that can be collected while the pet remains in its natural environment. These results demonstrate the concurrent and predictive validity of the IMU tested. Our long-range goal is to validate an open-source algorithm for the IMU so activity in a pet’s natural environment can be used as an outcome measure in future studies.

Open access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To determine if dogs with neoplasia produce more coated platelets, a subpopulation of activated platelets generated by dual stimulation with thrombin and convulxin, a glycoprotein VI agonist, than healthy control dogs.

ANIMALS

Client-owned dogs diagnosed with lymphoma (n = 19) or solid tumors (14) and healthy control dogs (14).

PROCEDURES

Platelets were stimulated ex vivo with thrombin and convulxin. Flow cytometry was used to quantify the percentage of coated platelets based on high levels of surface fibrinogen. To compare the percentage of coated platelets between the three groups, an ANOVA was performed followed by pairwise 95% confidence intervals (CI) adjusted for multiple comparisons using Tukey’s method.

RESULTS

We observed a greater mean percentage of coated platelets in dogs with solid tumors, compared with healthy control dogs, by 10.9 percentage points (95% CI: −1.0, 22.8), and a mean percentage of coated platelets in dogs with lymphoma that was less than healthy control dogs by 0.3 percentage points (95% CI: −11.4, 10.8).

CLINICAL RELEVANCE

This study provides the first data-based evidence that dogs with solid tumors may have a greater mean coated platelet percentage when compared with healthy control dogs, although there is overlap between groups. Further studies are needed investigating coated platelets in specific subsets of neoplasia and investigating additional mechanisms of hypercoagulability in dogs with neoplasia.

Open access
in American Journal of Veterinary Research