Objective: To determine the accuracy of 3-D and 2-D ultrasonography for quantification of tumor volume in dogs with transitional cell carcinoma (TCC) of the urinary bladder. Animals: 10 dogs with biopsy-confirmed TCC. Procedures: The urinary bladder of each dog was distended with saline (0.9% NaCl) solution (5.0 mL/kg), and masses were measured via 3-D and 2-D ultrasonography. Masses were also measured via 3-D ultrasonography after bladders were distended with 2.5 and 1.0 mL of saline solution/kg. Subsequently, the bladder was deflated and distended with CO2 (5.0 mL/kg); CT was performed after IV contrast medium administration. Tumor volumes were calculated via 3-D ultrasonography, 2-D ultrasonography, and CT (reference method) and compared via ANOVA, Deming regression, and Bland-Altman plots. Repeated-measures ANOVA was used to assess effects of bladder distension on 3-D tumor volume measurements. Repeatability of measurements was estimated via the coefficient of variation for each method. Results: Repeatability was considered good for all 3 methods. There was no significant difference in tumor volume measurements obtained via 3-D ultrasonography at different degrees of urinary bladder distension. Results of Deming regression and Bland-Altman plots indicated excellent agreement between tumor volume measurement with 3-D ultrasonography and CT, but not between 2-D ultrasonography and CT. Conclusions and Clinical Relevance: Tumor volume in dogs with TCC of the urinary bladder was accurately measured via 3-D ultrasonography. Use of 3-D ultrasonography can provide a less expensive and more practical method for monitoring response to treatment than CT and was more accurate than 2-D ultrasonography.

Objective: To examine the distribution of water in hoof wall specimens of horses via nuclear magnetic resonance (NMR) microscopy and determine changes in water distribution during hydration. Sample: 4 hoof wall specimens (2 obtained from the dorsum and 1 each obtained from the lateral quarter and lateral heel regions) of the stratum medium of healthy hooves of 1 horse. Procedures: Equine hoof wall specimens were examined via NMR microscopy. Proton density–weighted 3-D images were acquired. Changes during water absorption were assessed on sequential images. Results: The inner zone of the stratum medium had higher signals than did the outer zone. Areas of high signal intensity were evident in transverse images; these corresponded to the distribution of horn tubules. During water absorption, the increase in signal intensity started at the bottom of a specimen and extended to the upper region; it maintained the localization pattern observed before hydration. The relationship between the local maximal signals in areas corresponding to the horn tubules and minimal signal intensities in areas corresponding to the intertubular horn was similar and maintained approximately a linear distribution. Conclusions and Clinical Relevance: Based on the premise that signal intensity reflects water content, hydration in the equine hoof wall during water absorption occurred concurrently in the tubules and intertubular horn, and there was maintenance of the original water gradients. This technique can be applied for the assessment of pathophysiologic changes in the hoof wall on the basis of its hydration properties.

Objective: To noninvasively assess the influence of ingestion of a standard meal on gallbladder volume (GBV) in healthy cats. Animals: 10 healthy adult domestic shorthair cats (4 neutered females, 5 neutered males, and 1 sexually intact male). Procedures: Nonsedated cats were positioned in dorsal and left lateral recumbency to obtain ultrasonographic measurements of the gallbladder via the subcostal and right intercostal acoustic windows, respectively. Gallbladder volume was calculated from linear measurements by use of an ellipsoid formula (volume [mL] = length [mm] × height [mm] × width [mm] × 0.52). Measurements were recorded after food was withheld for 12 hours (0 minutes) and at 5, 15, 30, 45, 60, and 120 minutes after cats were fed 50 g of a standard commercial diet (protein, 44.3%; fat, 30.3%; and carbohydrate, 15.6% [dry matter percentage]). Results: Agreement between gallbladder linear measurements or GBV obtained from the subcostal and right intercostal windows was good. Feeding resulted in linear decreases in gallbladder linear measurements and GBV. Via the subcostal and intercostal windows, mean ± SD GBV was 2.47 ± 1.16 mL and 2.36 ± 0.96 mL, respectively, at 0 minutes and 0.88 ± 0.13 mL and 0.94 ± 0.25 mL, respectively, at 120 minutes. Gallbladder width most closely reflected postprandial modification of GBV. Conclusions and Clinical Relevance: Results indicated that ultrasonographic assessment (via the subcostal or right intercostal acoustic window) of postprandial changes in GBV can be used to evaluate gallbladder contractility in cats. These data may help identify cats with abnormal gallbladder emptying.

Objective: To evaluate the pharmacodynamic effects of dalteparin in dogs by means of viscoelastic coagulation monitoring with a thromboelastograph and a dynamic viscoelastic coagulometer. Animals: 6 healthy adult mixed-breed dogs. Procedures: Dalteparin (175 U/kg, SC, q 12 h) was administered for 4 days (days 1 through 4). Viscoelastic coagulation monitoring was performed hourly on the first and last days of treatment and included intermittent measurement of anti–activated coagulation factor X activity (AXA). Results: Dalteparin administration resulted in progressive hypocoagulability. On both day 1 and 4, activated clotting time and clot rate for the dynamic viscoelastic coagulometer differed significantly from baseline values, whereas the platelet function parameter did not change on day 1 but did on day 4. The R (reaction time), time from reaction time until the amplitude of the thromboelastography tracing is 20 mm, α-angle, and maximum amplitude differed from baseline values on days 1 and 4, although many thromboelastographic variables were not determined. The AXA was increased from baseline values at 3 and 6 hours after administration of the dalteparin injection on days 1 and 4, and all dogs had AXA values between 0.5 and 1.0 U/mL at 2 and 4 hours after administration. The AXA correlated well with activated clotting time (r = 0.761) and with R (r = 0.810), when values were available. Thromboelastography could not be used to distinguish AXA > 0.7 U/mL. Conclusions and Clinical Relevance: Viscoelastic coagulation monitoring with strong coagulation activators may be used to monitor treatment with dalteparin in healthy dogs.

Objective: To establish a safe anesthetic protocol with little effect on blood biochemical values and IV glucose tolerance test (IVGTT) results in Japanese black bears (Ursus thibetanus japonicus). Animals: 16 captive female Japanese black bears (5 to 17 years of age). Procedures: Bears were randomly assigned to 4 treatment groups (4 bears/group) in which various treatment combinations were administered via blow dart: tiletamine HCl and zolazepam HCl (9 mg/kg) alone (TZ), TZ (6 mg/kg) and acepromazine maleate (0.1 mg/kg), TZ (6 mg/kg) and butorphanol tartrate (0.3 mg/kg), or TZ (3 mg/kg) and medetomidine HCl (40 μg/kg). Glucose injection for the IVGTT was started 130 minutes after TZ administration. Blood samples were obtained before, at, and intermittently after glucose injection for measurement of biochemical variables as well as plasma glucose and serum insulin concentrations during the IVGTT. Rectal temperature, pulse rate, and respiratory rate were assessed every 15 minutes during the experiment. Results: Induction and maintenance of anesthesia were safely achieved with little adverse effect on cardiopulmonary function when each of the 4 anesthetic regimens was used, although mild hypothermia was induced. No difference was evident between treatment groups in blood biochemical values. Blood glucose and insulin concentration profiles during the IVGTT were similar among the bears given TZ, with or without acepromazine or butorphanol, but hyperglycemia and hypoinsulinemia developed in bears given TZ with medetomidine. Conclusions and Clinical Relevance: All 4 anesthetic regimens yielded chemical restraint without affecting clinical and biochemical values in bears, but medetomidine appeared to affect IVGTT results. For this reason, medetomidine should not be used when anesthetizing bears for IVGTTs.

Objective: To evaluate efficacy of a recombinant Moraxella bovis pilin-cytotoxin-Moraxella bovoculi cytotoxin subunit vaccine to prevent naturally occurring infectious bovine keratoconjunctivitis (IBK). Animals: 107 beef steers. Procedures: 2 groups of calves were inoculated SC with an immunostimulating complex (ISCOM) matrix adjuvant (control group; n = 54) or a recombinant M bovis pilin-cytotoxin–M bovoculi cytotoxin subunit antigen with the ISCOM matrix adjuvant (vaccine group; 53); calves received booster injections 21 days later. Calves were examined once weekly for 16 weeks. Investigators and herd managers were not aware of the inoculum administered to each calf throughout the trial. Primary outcome of interest was the cumulative proportion of calves that developed IBK. Serum samples were obtained before inoculation (day 0) and on days 42 and 112. Serum hemolysin-neutralizing titers against native M bovis and M bovoculi cytotoxin were determined. Results: No difference was detected between groups for the cumulative proportion of calves that developed IBK at weeks 8 and 16 after inoculation. Non–IBK-affected calves in the vaccine group had a significantly higher fold change in serum hemolysin-neutralizing titer against native M bovoculi cytotoxin from day 0 to 42 compared to control calves. Conclusions and Clinical Relevance: The M bovis pilin-cytotoxin-M bovoculi cytotoxin subunit vaccine with the ISCOM matrix adjuvant was not effective at preventing naturally occurring IBK. It is likely that the incorporation of additional protective antigens in a recombinant Moraxella spp subunit vaccine will be required to yield a product that can be used for effective immunization of cattle against IBK.

Objective: To determine the toxicokinetics of N-(methylsuccinimido)anthranoyllycoctonine–type low larkspur alkaloids in beef cattle. Animals: 5 Black Angus steers and 35 Swiss Webster mice. Procedures: Low larkspur (Delphinium andersonii) was collected, dried, ground, and administered to 5 steers via oral gavage to provide a dose of 12 mg of N-(methylsuccinimido)-anthranoyllycoctonine alkaloids/kg. Steers were housed in metabolism crates for 96 hours following larkspur administration; heart rate was monitored continuously, and blood samples were collected periodically for analysis of serum concentrations of 16-deacetylgeyerline, methyllycaconitine, geyerline, and nudicauline and assessment of kinetic parameters. The LD50 of a total alkaloid extract from D andersonii was determined in Swiss Webster mice. Results: The alkaloids were quickly absorbed, with a maximum serum concentration achieved within 18 hours after administration. Geyerline and nudicauline coeluted as 1 peak and were considered together for toxicokinetic analysis. Mean ± SD elimination half-life was 18.4 ± 4.4 hours, 15.6 ± 1.5 hours, and 16.5 ± 5.1 hours for 16-deacetylgeyerline, methyllycaconitine, and geyerline and nudicauline, respectively. There were significant differences in maximum serum concentration, amount absorbed, and distribution half-life among the 4 alkaloids. The mouse LD50 was 9.8 mg/kg. Conclusions and Clinical Relevance: Results suggested that clinical poisoning was likely to be most severe approximately 18 hours after exposure. Cattle should be closely monitored for at least 36 hours after initial exposure. Additionally, a withdrawal time of approximately 7 days would be required to clear > 99% of the toxic alkaloids from the serum of cattle that have ingested low larkspur.

Objective: To evaluate and compare bone modeling and remodeling in fractured and non-fractured central tarsal bones (CTBs) of racing Greyhounds. Sample: Paired cadaveric tarsi from 6 euthanized racing Greyhounds with right CTB fractures and 6 racing Greyhounds with other nontarsal injuries. Procedures: CTBs were dissected and fractured CTBs were reconstructed. Central tarsal bones were evaluated through standard and nonscreen high-detail radiography, computed tomography, and histologic examination. The bone mineral density (BMD) was calculated adjacent to fracture planes and as a gradient on sagittal computed tomographic images. Sagittal and transverse plane sections of bone were obtained and submitted for subjective histologic assessment. Linear mixed-effects models were used to compare findings. Results: Fractured right CTBs had greater BMD in the dorsal and midbody regions of the sagittal plane sections than did nonfractured CTBs. The BMD ratios from bone adjacent to the dorsal slab fracture planes were not different between fractured and nonfractured right CTBs. Conclusions and Clinical Relevance: Findings supported the existence of site-specific bone adaptation in CTBs of Greyhounds, with modeling and remodeling patterns that were unique to fractured right CTBs. The dorsal and midbody regions of fractured bones had greater BMD, and fractures occurred through these zones of increased BMD.

Objective: To describe the immunopathologic characteristics of superficial stromal immune-mediated keratitis (IMMK) immunopathologically by characterizing cellular infiltrate in affected corneas of horses. Animals: 10 client-owned horses with IMMK. Procedures: Immunohistochemical staining was performed on keratectomy samples with equine antibodies against the T-cell marker CD3 and B-cell marker CD79a (10 eyes) and the T-helper cytotoxic marker CD4 and T-cell cytotoxic marker CD8 (6 eyes). Percentage of positively stained cells was scored on a scale from 0 (no cells stained) to 4 (> 75% of cells stained). Equine IgG, IgM, and IgA antibodies were used to detect corneal immunoglobulin via direct immunofluorescence (10 eyes). Serum and aqueous humor (AH) samples from 3 horses with IMMK were used to detect circulating and intraocular IgG against corneal antigens via indirect immunofluorescence on unaffected equine cornea. Results: Percentage scores (scale, 0 to 4) of cells expressing CD3 (median, 2.35 [range, 0.2 to 3.7]; mean ± SD, 2.36 ± 1.08) were significantly greater than scores of cells expressing CD79a (median, 0.55 [range, 0 to 1.5]; mean, 0.69 ± 0.72). All samples stained positively for CD4- and CD8-expressing cells, with no significant difference in scoring. All samples stained positively for IgG, IgM, and IgA. No serum or AH samples collected from horses with IMMK reacted with unaffected equine cornea. Conclusions and Clinical Relevance: Pathogenesis of superficial stromal IMMK included cell-mediated inflammation governed by both cytotoxic and helper T cells. Local immunoglobulins were present in affected corneas; however, corneal-binding immunoglobulins were not detected in the serum or AH from horses with IMMK.

Objective: To determine whether preanalytic and analytic factors affect evaluation of the urinary protein-to-creatinine (UPC) ratio in dogs. Sample: 50 canine urine samples. Procedures: The UPC ratio was measured to assess the intra-assay imprecision (20 measurements within a single session), the influence of predilution (1:10, 1:20, and 1:100) for urine creatinine concentration measurement, and the effect of storage at room temperature (approx 20°C), 4°C, and −20°C. Results: The coefficient of variation at room temperature determined with the 1:20 predilution was < 10.0%, with the highest coefficients of variation found in samples with a low protein concentration or low urine specific gravity. This variability could result in misclassification of samples with UPC ratios close to the thresholds defined by the International Renal Interest Society to classify dogs as nonproteinuric (0.2), borderline proteinuric (0.21 to 0.50), or proteinuric (> 0.51). A proportional bias was found in samples prediluted 1:10, compared with samples prediluted 1:20 or 1:100. At room temperature, the UPC ratio did not significantly increase after 2 and 4 hours. After 12 hours at room temperature and at 4°C, the UPC ratio significantly increased. The UPC ratio did not significantly change during 3 months of storage at −20°C. Conclusions and Clinical Relevance: The intra-assay precision of the UPC ratio was sufficiently low to avoid misclassification of samples, except for values close to 0.2 or 0.5. The optimal predilution ratio for urine creatinine concentration measurement was 1:20. A 1:100 predilution is recommended in samples with a urine specific gravity > 1.030. The UPC ratio must be measured as soon as samples are collected. Alternatively, samples should be immediately frozen to increase their stability and minimize the risk of misclassification of proteinuria.