Long-term outcomes of thigh circumference, stifle range-of-motion, and lameness after unilateral tibial plateau levelling osteotomy.

Our study evaluated thigh circumference (TC), stifle range of motion (ROM), and lameness in dogs one to five years after unilateral tibial plateau levelling osteotomy (TPLO). We hypothesised that TC, stifle ROM, and lameness would not be different to the unoperated limb (control), one to five years after surgery. Patients that were one to five years post-TPLO were reviewed and were included if they had a unilateral TPLO, and no additional clinical evidence of orthopaedic disease. Standing mid-thigh TC measurements and stifle extension and flexion angles were made in triplicate. Clinical lameness was graded blindly. Data were evaluated statistically using paired t-tests for TC and stifle flexion and extension. Significance was set at p <0.05. Twenty-nine dogs met the inclusion criteria. Mean results for the surgery limbs and control limbs were 39.5 +/- 5.5 cm and 40.1 +/- 5.6 cm for TC, 36.6 +/- 6.8 degrees and 28.6 +/- 4.3 degrees for stifle flexion, and 155.2 +/- 6.6 degrees and 159.8 +/- 4.9 degrees for stifle extension, respectively. The mean TC for the operated limb was 98.5% of the control limb. A significant difference was found between the operated and the control limbs for all measurements. Time after surgery had no apparent affect on outcome. Four of 29 dogs (14%) exhibited some lameness in the TLPO limb during evaluation (one dog was 1 to 2 years postoperative and three dogs were 2 to 3 years postoperative). These results indicate that TC and stifle ROM in the TLPO limb do not return to control-limb measurements one to five years after a TPLO surgery. The clinical significance is unknown as TC returned to 98.5% of control, and the source of lameness in the lame dogs was not identified.

Preliminary studies of a canine 13C-aminopyrine demethylation blood test.

The objectives of this study were to determine whether a 13C-aminopyrine demethylation blood test is technically feasible in clinically healthy dogs, whether oral administration of 13C-aminopyrine causes a detectable increase in percent dose/min (PCD) of 13C administered as 13C-aminopyrine and recovered in gas extracted from blood, and whether gas extraction efficiency has an impact on PCD. A dose of 2 mg/kg body weight of 13C-aminopyrine dissolved in deionized water was administered orally to 6 clinically healthy dogs. Blood samples were taken from each dog 0, 30, 60, and 120 min after administration of the 13C-aminopyrine. Carbon dioxide was extracted from blood samples by addition of acid and analyzed by fractional mass spectrometry. None of the 6 dogs showed any side effects after 13C-aminopyrine administration. All 6 dogs showed a measurable increase of the PCD in gas samples extracted from blood samples at 30 min, 60 min, and 120 min after 13C-aminopyrine administration. Coefficients of variation between the triplicate samples were statistically significantly higher for the %CO2, a measure of extraction efficiency, than for PCD values (P < 0.0001). The 13C-aminopyrine demethylation blood test described here is technically feasible. Oral administration of 13C-aminopyrine did not lead to gross side effects in the 6 dogs. Clinically healthy dogs show a measurable increase of PCD in gas extracted from blood samples after oral administration of 13C-aminopyrine. Efficiency of CO2 extraction from blood samples does not have an impact on PCD determined from these blood samples. This test may prove useful to evaluate hepatic function in dogs.

Development and validation of a method for simultaneous separation and quantification of 5 different sugars in canine urine.

The objective of this project was to develop and validate a method for concurrent separation and quantification of methylglucose, rhamnose, xylose, sucrose, and lactulose in canine urine by using high pressure anion exchange liquid chromatography and pulsed amperometric detection. The method was validated by evaluating dilutional parallelism, spiking recovery, intra-assay variability, and inter-assay variability. Observed to expected ratios for 3 urine samples, and all sugars, ranged from 77.6% to 106.9% for a 1:2 dilution, 85.2% to 121.4% for a 1:4 dilution, and 91.6% to 163.7% for a 1:8 dilution. Observed to expected ratios for spiking recovery of 3 urine samples, all sugars, and 5 different spiking solutions, ranged from 85.5% to 116.7 % (mean +/- SD, 100.5 +/- 6.0%). The intra-assay coefficients of variation were 1.6%, 3.4%, and 4.7% for methylglucose; 1.6%, 2.0%, and 3.6% for rhamnose; 2.7%, 1.4%, and 1.1% for xylose; 9.8%, 3.4%, and 4.0% for sucrose; and 3.2%, 3.3%, and 3.3% for lactulose. Inter-assay coefficients of variation were 3.2%, 5.7%, and 4.2% for methylglucose; 4.3%, 5.4%, and 6.4% for rhamnose; 3.3%, 5.0%, and 4.2% for xylose; 9.4%, 9.9%, and 9.4% for sucrose; and 6.1%, 4.9%, and 2.7% for lactulose. In conclusion, a method for simultaneous separation and quantification of 5 sugars in canine urine was established and found to be linear, accurate, precise, and reproducible. This method may prove useful in the simultaneous evaluation of gastric permeability, small intestinal permeability, and small intestinal mucosal function in dogs with gastrointestinal disorders.

Development and validation of an enzyme-linked immunosorbent assay for feline trypsin-like immunoreactivity.

OBJECTIVE: To develop and validate an ELISA for quantitative analysis of feline trypsin-like immunore-activity (fTLI). SAMPLE POPULATION: Purified feline cationic trypsin (fCT) and rabbit anti-fCT antiserum; blood samples from 63 healthy cats. PROCEDURES: A sandwich capture ELISA was developed, using anti-fCT antiserum purified by affinity chromatography that underwent biotinylation. Purified fCT was used for standards. The assay was validated by determination of sensitivity, working range, linearity, accuracy, precision, and reproducibility. A reference range was established by assaying serum samples from the 63 healthy cats. RESULTS: Sensitivity was 1.23 microg/L; working range was 2 to 567 microg/L. Ratios of observed versus expected results for 4 samples tested at various dilutions ranged from 90.0 to 120.7%. Ratios of observed versus expected results for 5 samples spiked with various concentrations of fCT ranged from 82.0 to 101.8%. Intra- and inter-assay coefficients of variability ranged from 9.9 to 11.1% and from 10.2 to 21.7%, respectively. The reference range for serum fTLI measured with this ELISA was 12 to 82 microg/L. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that an ELISA can be used to measure serum fTLI in cats. The ELISA was sufficiently sensitive, linear, accurate, precise, and reproducible for clinical use.