Breast tumors are the most common tumors in dogs and the study of disease prognostic factors is important for establishing the appropriate treatment protocols. The purpose of this study was to clinically stage mammary tumors of bitches and correlate the stages with histological type and grade. The tumors of 63 dogs were clinically staged based on the findings of tumor sizing, lymph node evaluation, and radiographic examination. After surgical excision, the tumors were classified histologically and graded. The relationship between the tumor grade, stage, and histological type was evaluated using a binomial test. Stage I tumors were the most numerous (31.75%), followed by tumors at stages II, III, IV, and V. Animals with histological grade I carcinomas presented stage I, II, or III tumors more frequently and stage IV and V tumors less frequently. The number of animals with simple carcinomas that were at stage I of the disease was greater than that at stage V. Carcinomas in the mixed tumors were less aggressive; however, the small number of animals in stage V of the disease made any statistical association impossible. The complex carcinomas presented with the invasion of the lymph nodes and less cellular differentiation in a larger number of animals than did simple carcinomas. Histological grading proved to be the best parameter for the prognostic evaluation of the breast carcinomas.

OBJECTIVE To characterize the elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate (CSH) beads in vitro. SAMPLE 60 carboplatin-impregnated CSH beads and 9 CSH beads without added carboplatin (controls). PROCEDURES Carboplatin-impregnated CSH beads (each containing 4.6 mg of carboplatin [2.4 mg of platinum]) were placed into separate 10-mL plastic tubes containing 5 mL of PBSS in groups of 1, 3, 6, or 10; 3 control beads were placed into a single tube of PBSS at the same volume. Experiments were conducted in triplicate at 37°C and a pH of 7.4 with constant agitation. Eluent samples were collected at 1, 2, 3, 6, 12, 24, and 72 hours. Samples were analyzed for platinum content by inductively coupled plasma–mass spectrometry. RESULTS The mean concentration of platinum released per carboplatin-impregnated bead over 72 hours was 445.3 mg/L. Cumulative concentrations of platinum eluted increased as the number of beads per tube increased. There was a significant difference in platinum concentrations over time, with values increasing over the first 12 hours and then declining for all tubes. There was also a significant difference in percentage of total incorporated platinum released into tubes with different numbers of beads: the percentage of eluted platinum was higher in tubes containing 1 or 3 beads than in those containing 6 or 10 beads. CONCLUSIONS AND CLINICAL RELEVANCE Carboplatin-impregnated CSH beads eluted platinum over 72 hours. Further studies are needed to determine whether implantation of carboplatin-impregnated CSH beads results in detectable levels of platinum systemically and whether the platinum concentrations eluted locally are toxic to tumor cells.

OBJECTIVE To assess the pharmacokinetic properties of cefovecin in a cold-water teleost species. ANIMALS 10 healthy adult copper rockfish (Sebastes caurinus), sex unknown. PROCEDURES Cefovecin (16 mg/kg) was administered SC to the rockfish. Blood samples were collected at predetermined points for measurement of plasma cefovecin concentrations (3 samples/fish). Plasma cefovecin concentrations were measured via liquid chromatography with mass spectrometry. Pharmacokinetic analysis was performed by means of naïve pooled analysis and compartmental modeling. Plasma protein binding of cefovecin was determined by ultrafiltration. RESULTS Cefovecin administration appeared to be well tolerated by the rockfish. Pharmacokinetic analysis resulted in a maximum plasma concentration of 104.8 μg/mL at 2.07 hours after administration. Plasma terminal half-life was 32.5 hours, and area under the curve was 5,132 h·g/mL. Plasma protein binding was low (< 10%) for plasma concentrations of 10 and 100 μg of cefovecin/mL when assessed at 7.8° and 20°C. Plasma concentrations > 1 μg/mL persisted for the full 7-day follow-up period. CONCLUSIONS AND CLINICAL RELEVANCE SC administration of cefovecin to copper rockfish at a dose of 16 mg/kg yielded plasma concentrations > 1 μg/mL that persisted to 7 days, but some interindividual variability was observed. The low degree of plasma protein binding but high circulating concentration of free drug may allow an extended administration interval in rockfish. Studies are needed to assess the efficacy and safety of this dose in rockfish.

OBJECTIVE To evaluate 2 processing methods (commercial kit vs conical tube centrifugation) for preparing platelet rich plasma (PRP) for use in llamas and alpacas. SAMPLES Blood samples (30 mL each) aseptically collected from 6 healthy llamas and 6 healthy alpacas. PROCEDURES PRP was prepared from blood samples by use of a commercial kit and by double-step conical tube centrifugation. A CBC was performed for blood and PRP samples. Platelets in PRP samples were activated by means of a freeze-thaw method with or without 23mM CaCl2, and concentrations of platelet-derived growth factor-BB and transforming growth factor-β1 were measured. Values were compared between processing methods and camelid species. RESULTS Blood CBC values for llamas and alpacas were similar. The commercial kit yielded a significantly greater degree of platelet enrichment (mean increase, 8.5 fold vs 2.8 fold) and WBC enrichment (mean increase, 3.7 fold vs 1.9 fold) than did conical tube centrifugation. Llamas had a significantly greater degree of platelet enrichment than alpacas by either processing method. No difference in WBC enrichment was identified between species. Concentrations of both growth factors were significantly greater in PRP samples obtained by use of the commercial kit versus those obtained by conical tube centrifugation. CONCLUSIONS AND CLINICAL RELEVANCE For blood samples from camelids, the commercial kit yielded a PRP product with a higher platelet and WBC concentration than achieved by conical tube centrifugation. Optimal PRP platelet and WBC concentrations for various applications need to be determined for llamas and alpacas.

OBJECTIVE To compare left ventricle (LV) volume and function variables obtained by use of 1-D, 2-D, and real-time 3-D echocardiography versus ECG-gated multidetector row CT (MDCT) angiography, which was considered the criterion-referenced standard. ANIMALS 6 healthy, purpose-bred dogs. PROCEDURES Dogs were anesthetized and administered a constant rate infusion of esmolol, and 1-D, 2-D, and 3-D echocardiography and ECG-gated, contrast-enhanced MDCT were performed. End-diastolic volume (EDV), end-systolic volume (ESV), stroke volume, and ejection fraction (EF) were calculated by use of the Teichholz method for 1-D echocardiography, single-plane and biplane modified Simpson method of disks (MOD) and area-length method for 2-D echocardiography, and real-time biplane echocardiography (RTBPE) and real-time 3-D echocardiography (RT3DE) for 3-D echocardiography. Volumes were indexed to body surface area and body weight. Median values, correlations, and limits of agreement were compared between echocardiographic modalities and MDCT. RESULTS EDV and ESV measured by use of RTBPE and RT3DE had the strongest correlations with results for MDCT. Values obtained for EDV, ESV, stroke volume, and EF did not differ significantly between echocardiographic methods and MDCT. Use of RT3DE and RTBPE slightly underestimated EDV, ESV, and EF, compared with values for MDCT, as determined with Bland-Altman analysis. CONCLUSIONS AND CLINICAL RELEVANCE Values for EDV and ESV obtained by use of 3-D echocardiography, including RTBPE and RT3DE, had the highest correlation with slight underestimation, compared with values obtained by use of MDCT. This was similar to results for 3-D echocardiography in human medicine.

OBJECTIVE To evaluate the effects of selective hip joint denervation on gait abnormalities and signs of hip joint pain in dogs. ANIMALS 6 healthy adult hound-type dogs. PROCEDURES Minimally invasive denervation was performed on the right hip joint of each dog. Two weeks later, sodium urate was injected into the right hip joint to induce synovitis. Dogs were evaluated clinically and by use of instrumented gait analysis before and 2 weeks after minimally invasive denervation and 4, 8, and 24 hours after induction of synovitis. Dogs were euthanized, and necropsy and histologic examination were performed. RESULTS No kinetic or kinematic gait modifications were detected 2 weeks after minimally invasive denervation. Denervation did not eliminate signs of pain and lameness associated with sodium urate–induced synovitis. Results of histologic examination confirmed that denervation was an effective method for transecting the innervation of the craniolateral and caudolateral aspects of the hip joint capsule. CONCLUSIONS AND CLINICAL RELEVANCE In this study, minimally invasive denervation did not result in gait modifications in dogs. Denervation did not abolish the signs of pain and lameness associated with generalized induced synovitis of the hip joint. Further studies are required before conclusions can be drawn regarding the clinical usefulness of hip joint denervation for dogs with hip dysplasia.

OBJECTIVE To determine values of perfusion parameters determined via MRI in the brains of healthy dogs. ANIMALS 10 healthy adult Beagles. PROCEDURES Each dog was anesthetized for MRI examination of the brain, including standard sequences and a perfusion-weighted sequence. Gadoteric acid (0.2 mmol/kg) was injected IV at a rate of 5 mL/s. A dedicated workstation was used to measure the times from contrast medium injection to arrival at an ROI (TO) and peak contrast enhancement (TTP), mean contrast medium transport time (MTT), and cerebral blood flow (CBF) in the caudate nucleus, thalamus, piriform lobe, hippocampus, semioval center, and temporal cerebral cortex. A simple mathematical model was used to compare parameter values among the various brain regions. RESULTS T0 and time to peak contrast enhancement had a significant linear relationship. A significant negative correlation was identified between T0 and CBF and, to a lesser extent, between MTT and CBF. Differences among brain regions were significant for MTT and CBF. The CBF was lowest in the semioval center, and the piriform lobe had almost 2-fold the CBF of that region. No significant differences were identified between hemispheres of the brain. CONCLUSIONS AND CLINICAL RELEVANCE Findings obtained in this study involving healthy dogs may serve as a reference for MRI perfusion measurements in specific brain regions and may help in the characterization of various brain diseases in dogs.

OBJECTIVE To compare the effectiveness of an ultrasound-guided paravertebral nerve blockade technique (UGPNB) with distal and proximal paravertebral nerve blockade techniques without ultrasound guidance (DPNB and PPNB, respectively) in calves. ANIMALS 4 calf cadavers and 7 healthy calves. PROCEDURES A suitable acoustic window was identified to facilitate access to the T13, L1, and L2 spinal nerves in cadavers and live calves. In cadavers, nerves were injected with dye under ultrasound guidance. In calves, the UGPNB, DPNB, and PPNB were performed in random order at 10-day intervals by injection of an anesthetic solution containing 2% lidocaine hydrochloride. Nociceptive withdrawal responses were assessed to determine the effects of the blockades. RESULTS In cadavers, nerve staining success rates (ie, ≥ 2-cm-long dye path) achieved with ultrasound guidance were 88% (T13 [ventral branch]), 75% (T13 and L1 [dorsal branches] and L1 and L2 [ventral branches]), and 38% (L2 [dorsal branch]). The nerves were each identified as a hyperechoic band in a longitudinal plane. In calves, the UGPNB, DPNB, and PPNB reduced the withdrawal response to the noxious stimulus, mainly in the dorsal-cranial, dorsal-caudal, and ventral-cranial areas of the flank. Overall, the UGPNB resulted in a better nociceptive cumulative score, administering only one half of the local anaesthetic dose, compared with findings for the DPNB and PPNB. However, time to perform the UGPNB was longer. CONCLUSIONS AND CLINICAL RELEVANCE The UGPNB evaluated may be an improved alternative to the DPNB and PPNB for provision of anesthesia for flank surgery in calves. However, effectiveness of the UGPNB should be evaluated in a clinical setting and in adult cattle.

Mycobacterium avium ssp. paratuberculosis (MAP) is the etiologic agent of Johne’s disease, a chronic contagious enteritis of ruminants that causes major economic losses. Several studies, most involving large free-stall herds, have found environmental sampling to be a suitable method for detecting MAP-infected herds. In eastern Canada, where small tie-stall herds are predominant, certain conditions and management practices may influence the survival and transmission of MAP and recovery (isolation). Our objective was to estimate the performance of a standardized environmental and targeted pooled sampling technique for the detection of MAP-infected tie-stall dairy herds. Twenty-four farms (19 MAP-infected and 5 non-infected) were enrolled, but only 20 were visited twice in the same year, to collect 7 environmental samples and 2 pooled samples (sick cows and cows with poor body condition). Concurrent individual sampling of all adult cows in the herds was also carried out. Isolation of MAP was achieved using the MGIT Para TB culture media and the BACTEC 960 detection system. Overall, MAP was isolated in 7% of the environmental cultures. The sensitivity of the environmental culture was 44% [95% confidence interval (CI): 20% to 70%] when combining results from 2 different herd visits and 32% (95% CI: 13% to 57%) when results from only 1 random herd visit were used. The best sampling strategy was to combine samples from the manure pit, gutter, sick cows, and cows with poor body condition. The standardized environmental sampling technique and the targeted pooled samples presented in this study is an alternative sampling strategy to costly individual cultures for detecting MAP-infected tie-stall dairies. Repeated samplings may improve the detection of MAP-infected herds.

OBJECTIVE To determine degrees of production of cyclooxygenase (COX)-1 and -2 and other mediators of inflammation in noninflamed and inflamed skin and muscle tissues in ball pythons (Python regius). ANIMALS 6 healthy adult male ball pythons. PROCEDURES Biopsy specimens of noninflamed skin and muscle tissue were collected from anesthetized snakes on day 0. A 2-cm skin and muscle incision was then made 5 cm distal to the biopsy sites with a CO2 laser to induce inflammation. On day 7, biopsy specimens of skin and muscle tissues were collected from the incision sites. Inflamed and noninflamed tissue specimens were evaluated for production of COX-1, COX-2, phosphorylated protein kinase B (AKT), total AKT, nuclear factor κ-light-chain-enhancer of activated B cells, phosphorylated extracellular receptor kinases (ERKs) 1 and 2, and total ERK proteins by western blot analysis. Histologic evaluation was performed on H&E-stained tissue sections. RESULTS All biopsy specimens of inflamed skin and muscle tissues had higher histologic inflammation scores than did specimens of noninflamed tissue. Inflamed skin specimens had significantly greater production of COX-1 and phosphorylated ERK than did noninflamed skin specimens. Inflamed muscle specimens had significantly greater production of phosphorylated ERK and phosphorylated AKT, significantly lower production of COX-1, and no difference in production of COX-2, compared with production in noninflamed muscle specimens. CONCLUSIONS AND CLINICAL RELEVANCE Production of COX-1, but not COX-2, was significantly greater in inflamed versus noninflamed skin specimens from ball pythons. Additional research into the reptilian COX signaling pathway is warranted.