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Objective—To compare bursting pressures in canine jejunum, measured by use of an in vitro and an in situ bursting pressure technique.

Study Population—Cadavers of 3 healthy adult dogs.

Procedures—54 enterotomies were performed on 3 canine cadavers immediately after euthanasia. After completion of enterotomy closure, bursting pressure was measured on 9 jejunal segments by use of an in situ technique and on 9 jejunal segments by use of an in vitro technique for each canine cadaver. Bursting pressure testing time was recorded for both in situ and in vitro techniques. Techniques were compared by means of randomized block ANOVA.

Results—The mean ± SE in vitro and in situ bursting pressures were 93.63 ± 24.10 mm Hg and 141.19 ± 38.10 mm Hg and were not significantly different. Mean in situ testing time was 40.7 min/cadaver; mean in vitro testing time was 50.3 min/cadaver.

Conclusions and Clinical Relevance—The in situ bursting pressure testing technique yielded results similar to those of the in vitro method, was somewhat less labor-intensive, and may be applicable to future studies of live dogs.

Full access
in American Journal of Veterinary Research


Objective—To determine the minimal ultrasonic aspirator pressure necessary to damage the cerebral cortex of healthy dogs.

Animals—9 mixed-breed dogs.

Procedure—The study comprised 2 parts. In part A, 6 dogs were euthanatized immediately prior to the experiment. In part B, 3 dogs were anesthetized for recording of physiologic variables. In both parts, craniectomy and durotomy were performed to bilaterally expose the lateral aspect of the cerebral cortex. An ultrasonic aspirator was placed in contact with various areas of the cerebral cortex, and aspirator power was altered (10, 20, 30, and 40%). Duration of contact at each power was 5 and 10 seconds. Subsequently, gross morphologic and histologic damage was assessed in the cortex.

Results—Gross observations for all dogs were similar. At 10% power, visible or histologic damage was not evident in the cortex. At 20% power, the cortex was slightly indented from contact with the hand piece; however, cortical disruption was not evident. Cortical disruption was initially detectable at 30% power in some dogs and was consistently evident at 40% power in both sets of dogs.

Conclusions and Clinical Relevance—Ultrasonic aspirator power of < 20% created minimal acute morphologic damage to the cortex. Power settings between 20 and 30% may superficially damage the cerebral cortex in healthy dogs, whereas 40% power consistently damages the cerebral cortex. Knowledge of the degree of damage to cerebral cortex caused by various amounts of power for ultrasonic aspirators will allow surgeons to avoid damaging normal brain tissues during surgery. (Am J Vet Res 2001;62: 248–251)

Full access
in American Journal of Veterinary Research


Objective—To determine whether Border Collies (ATP binding cassette subfamily B1 gene [ABCB1] wildtype) were more likely than other breeds to develop vincristine-associated myelosuppression (VAM) and, if so, whether this was caused by a mutation in ABCB1 distinct from ABCB1-1Δ.

Animals—Phase 1 comprised 36 dogs with the ABCB1 wildtype, including 26 dogs with lymphoma (5 Border Collies and 21 dogs representing 13 other breeds) treated with vincristine in a previous study; phase 2 comprised 10 additional Border Collies, including 3 that developed VAM and 7 with an unknown phenotype.

Procedures—For phase 1, the prevalence of VAM in ABCB1-wildtype Border Collies was compared with that for ABCB1-wildtype dogs of other breeds with data from a previous study. For phase 2, additional Border Collies were included. Hematologic adverse reactions were graded with Veterinary Co-operative Oncology Group criteria. Genomic DNA was used to amplify and sequence all 27 exons of the canine ABCB1. Sequences from affected dogs were compared with those of unaffected dogs and dogs of unknown phenotype.

Results—3 of 5 Border Collies with the ABCB1 wildtype developed VAM; this was significantly higher than the proportion of other dogs that developed VAM (0/21). A causative mutation for VAM in Border Collies was not identified, although 8 single nucleotide polymorphisms in ABCB1 were detected.

Conclusions and Clinical Relevance—Breed-associated sensitivity to vincristine unrelated to ABCB1 was detected in Border Collies. Veterinarians should be aware of this breed predisposition to VAM. Causes for this apparent breed-associated sensitivity should be explored.

Full access
in American Journal of Veterinary Research


Objective—To determine the incidence of and risk factors for postoperative regurgitation and vomiting (PORV) in dogs.

Design—Retrospective cohort study.

Animals—244 client-owned dogs.

Procedures—Dogs referred for nonelective surgery in the first 3 months of 2000 and 2012 were included. Breed; sex; age; weight; body condition score; emergency status; food withholding status; history of vomiting or regurgitation; American Society of Anesthesiologists score; presence of diabetes or hypothyroidism; preoperative PCV and total solids concentration; anesthesia protocol; corticosteroid, opioid, neuromuscular blocking agent, and nitrous oxide usage; anesthesia time; surgery time; type of surgery; and occurrence of vomiting or regurgitation within 24 hours after recovery from anesthesia were recorded. Data were analyzed by means of the Fisher exact test, Wilcoxon rank sum test, and logistic regression.

Results—30 of 244 (12.3%) dogs meeting study inclusion criteria developed PORV. There was no significant difference in the incidence of PORV between the 2000 (12/111 [10.8%]) and 2012 (18/133 [13.5%]) cohorts, although the incidence of regurgitation was higher in 2012. Univariate logistic regression identified the most significant risk factors as gastrointestinal surgery (OR, 11.15; 95% confidence interval [CI], 3.11 to 40.03), premedication without strong sedatives including either an α2-adrenoceptor agonist or acepromazine (OR, 5.36; 95% CI, 1.89 to 15.17), American Society of Anesthesiologists score of 4 (OR, 5.25; 95% CI, 1.05 to 26.15), history of vomiting or regurgitation (OR, 5.12; 95% CI, 1.83 to 14.31), emergency surgery (OR, 4.08; 95% CI, 1.29 to 12.90), neurologic surgery (OR, 3.18; 95% CI, 1.02 to 9.92), sevoflurane inhalation anesthesia (OR, 2.78; 95% CI, 1.25 to 6.13), and being sexually intact (OR, 2.37; 95% CI, 1.07 to 5.27). Multivariate analysis was not clinically useful owing to the low sensitivity and specificity of the model.

Conclusions and Clinical Relevance—Between 2000 and 2012, there was no change in the incidence of PORV for dogs undergoing neurologic, orthopedic, and soft tissue surgical procedures; however, the proportion of dogs that regurgitated increased significantly in 2012. Preoperative antiemetic prophylaxis should be considered in dogs undergoing gastrointestinal surgery and in those in which other risk factors are present.

Full access
in Journal of the American Veterinary Medical Association


Objective—To compare plasma disposition of alkaloids after lupine challenge in cattle that had given birth to calves with lupine-induced arthrogryposis and cattle that had given birth to clinically normal calves and determine whether the difference in outcome was associated with differences in plasma disposition of anagyrine.

Animals—6 cows that had given birth to calves with arthrogryposis and 6 cows that had given birth to clinically normal calves after being similarly exposed to lupine during pregnancy.

Procedure—Dried lupine (2 g/kg) was administered via gavage. Blood samples were collected before and at various time points for 48 hours after lupine administration. Anagyrine, 5,6-dehydrolupanine, and lupanine concentrations in plasma were measured by use of gas chromatography. Plasma alkaloid concentration versus time curves were generated for each alkaloid, and pharmacokinetic parameters were determined for each cow.

Results—No significant differences in area under the plasma concentration versus time curve, maximum plasma concentration, time to reach maximum plasma concentration, and mean residence time for the 3 alkaloids were found between groups.

Conclusions and Clinical Relevance—Because no differences were found in plasma disposition of anagyrine following lupine challenge between cattle that had given birth to calves with arthrogryposis and those that had not, our findings do not support the hypothesis that between-cow differences in plasma disposition of anagyrine account for within-herd differences in risk for lupine-induced arthrogryposis. (Am J Vet Res 2004;65:1580–1583)

Full access
in American Journal of Veterinary Research


Objective—To characterize the magnitude and duration of the antibody response against human albumin (HA) in critically ill and healthy dogs.

Design—Cohort and cross-sectional study.

Animals—Fourteen critically ill dogs that received 25% HA as part of their treatment protocol, 2 healthy dogs with no known previous exposure to HA that received 2 infusions of 25% HA (positive control dogs), and 47 healthy dogs and 21 critically ill dogs with no known exposure to HA (negative control dogs).

Procedures—An ELISA to detect IgG against HA was developed. Serum samples were obtained from the critically ill dogs prior to infusion of HA, at the time of hospital discharge, and 4 to 6 weeks and 6 months after HA administration. Serum samples were obtained at 2- to 4-week intervals from both positive control dogs for 101 weeks. A single serum sample was obtained from each of the negative control dogs.

Results—All 14 critically ill dogs developed serum IgG against HA. Peak antibody response was detected 4 to 6 weeks after HA administration. In both positive control dogs, IgG against HA was detected 10 days after HA administration and continued past 97 weeks. The peak antibody response was detected at 3 weeks in 1 dog and at 9 weeks in the other. Five of the 68 (7%) negative control dogs had a positive antibody response.

Conclusions and Clinical Relevance—Results suggested that dogs developed a pronounced IgG response following exposure to HA and that some dogs with no history of HA administration were positive for anti-HA IgG.

Full access
in Journal of the American Veterinary Medical Association



To determine whether addition of an optional clinical skills laboratory (OCSL) to the traditional surgery curriculum would affect total surgery time or incision closure time in veterinary students performing ovariohysterectomy of a dog during a third-year surgery course.


Retrospective and prospective study of veterinary student attendance at OCSL sessions and student performance during the third-year surgery course.


Students from the classes of 2012, 2013, and 2014 at the Washington State University College of Veterinary Medicine.


For all students, total surgery time and incision closure time were recorded when students performed an ovariohysterectomy of a dog during their third-year live-animal surgery course. Times were analyzed to identify differences among classes and determine whether times were associated with number of OCSL sessions attended, previous experience performing ovariohysterectomies, or enrollment in an elective clinical skills course.


Total surgery and incision closure times were not significantly different between students in the class of 2012 (no access to the OCSL prior to the third-year surgery course) and students in the class of 2013 (ie, access to 4 OCSL sessions during the spring semester prior to the third-year surgery course). However, times were significantly shorter for students in the class of 2014 (ie, students who had access to OCSL sessions during the 3 semesters prior to the third-year surgery course) than for students in the other 2 classes.


Results suggested that attendance in the OCSL sessions was associated with improvements in surgical performance, as reflected in faster total surgery and incision closure times while performing an ovariohysterectomy during the third-year surgery course.

Full access
in Journal of the American Veterinary Medical Association