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Summary

Clinical findings and laboratory test results from 91 cats with chronic conjunctivitis were studied to determine the causes of the disease and the sensitivity of diagnostic procedures used, and to identify correlations between results of various diagnostic procedures and clinical or signalment variations. Mean age of affected cats was 2.9 ± 2.7 years (± sd), with a range from 1 month to 11 years. Conjunctivitis was more likely to be bilateral (56 cats) than unilateral (35 cats). In cats tested for FeLV or feline immunodeficiency virus infection, 15 and 8.5%, respectively, of the results were positive, compared with 4 and 2.6% for the general hospital population. Culturing or immunofluorescent assay (ifa) for feline herpesvirus 1 (fhv-1) and Chlamydia psittaci ifa resulted identification of pathogens (positive test results) in 19% (fhv-1) and 18% (C psittaci) of tested cats. For fhv-1, culturing was more sensitive than was ifa, yielding positive results in 19 vs 8.8% of cases. In only 1 cat were fhv-1 and chlamydiae recovered. The probability of positive test results for fhv-1 or chlamydiae was unrelated to concurrent corneal disease, unilateral vs bilateral involvement, or age. Cause of conjunctivitis could not be definitively determined in the remaining 35 cases tested for both agents. Bacterial species considered to be potentially pathogenic were isolated from conjunctival sac specimens in only 1 of 38 attempts. Cytologic changes considered compatible with chlamydial or fhv-1 infection (intracytoplasmic inclusions or multinucleated epithelial cells, respectively) were found in 8 and 5 cases, respectively. In only 4 of these cases, however, was the cytologic impression supported by a concurrently positive result on antigen-detection testing. This study revealed that routinely used diagnostic procedures were not able to confirm an etiologic diagnosis in most cats with chronic conjunctivitis.

Free access
in Journal of the American Veterinary Medical Association

SUMMARY

A study was conducted to determine the effect of monophosphoryl lipid A (mpl) and trehalose dimycolate (tdm) as adjuvants on the protective responses in balb/c mice vaccinated with Brucella abortus salt-extractable protein (bcsp) or proteinase-K-treated B abortus lipopolysaccharide (pklps). Mice were vaccinated with different doses of bcsp or pklps given alone or in combination with mpl or tdm. Mice were challenge-exposed 4 weeks later with virulent B abortus strain 2308. Two weeks after challenge exposure, the number of B abortus colony-forming units (cfu) per spleen, spleen weights, and spleen cell interleukin 1 production were measured. Serum IgG and IgM concentrations specific for vaccinal immunogens were measured before and after challenge exposure with B abortus.

Spleen weights and mean B abortus cfu per vaccine group were significantly lower in bcsp- and pklps-vaccinated mice, compared with those of nonvaccinated control mice. Monophosphoryl lipid A enhanced the suppression of splenic infection when given with the bcsp vaccine, but not when given with the pklps vaccine. Trehalose dimycolate had no effect on mean cfu when given with bcsp, but incorporation of tdm resulted in a significant increase in mean cfu when given with pklps. Spleen weights in bcsp- or pklps-vaccinated mice were not different when these vaccines were combined with mpl or tdm. Because of the wide variation in the results, we could not conclude that vaccination with bcsp or pklps alone, or in combination with mpl altered spleen cell interleukin-1 production in B abortus-infected mice. Increased host protection as defined by decreased cfu could not be related consistently to increased bcsp- or pklps-specific serum IgG or IgM antibodies introduced by any of the vaccines. These results do not eliminate a role for antibodies in the protection observed.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine pharmacokinetics of meloxicam in healthy green iguanas following PO and IV administration and assess potential toxicity.

Animals—21 healthy green iguanas (Iguana iguana).

Procedures—To assess pharmacokinetics, 13 iguanas were administered a single dose (0.2 mg/kg) of meloxicam PO and, 14 days later, the same dose IV. To assess potential toxicity, 4 iguanas were given meloxicam at a dosage of 1 or 5 mg/kg, PO, every 24 hours for 12 days, and results of histologic examination were compared with results for another 4 iguanas given a single dose of meloxicam (0.2 mg/kg).

Results—There were no significant differences between PO and IV administration with regard to terminal half-life (mean ± SD, 12.96 ± 8.05 hours and 9.93 ± 4.92 hours, respectively), mean area under the curve to the last measured concentration (5.08 ± 1.62 μg•h/mL and 5.83 ± 2.49 μg•h/mL), volume of distribution (745 ± 475 mL/kg and 487 ± 266 mL/kg), or clearance (40.17 ± 10.35 mL/kg/h and 37.17 ± 16.08 mL/kg/h). Maximum plasma concentration was significantly greater following IV (0.63 ± 0.17 μg/mL) versus PO (0.19 ± 0.07 μg/mL) administration. Time from administration to maximum plasma concentration and mean residence time were significantly longer following PO versus IV administration. Daily administration of high doses (1 or 5 mg/kg) for 12 days did not induce any histologic changes in gastric, hepatic, or renal tissues.

Conclusions and Clinical Relevance—Results suggested that administration of meloxicam at a dose of 0.2 mg/kg IV or PO in green iguanas would result in plasma concentrations > 0.1 μg/mL for approximately 24 hours. (Am J Vet Res 2010;71:1277–1283)

Full access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

To identify the rate at which medication errors occurred over a 2-year period in a large animal veterinary teaching hospital and describe the types of errors that occurred.

SAMPLE

226 medication errors over 6,155 large animal visits occurred during the study period. Multiple errors may have affected the same patient.

METHODS

Medication error reports from March 1, 2021, to March 31, 2023, were reviewed retrospectively and classified by species, type of drug, and month and day of the week the error occurred. Errors were categorized according to multiple previously developed systems to allow for comparison to other studies.

RESULTS

226 medication errors occurred over 6,155 patient visits in a 2-year period: 57.5% (130/226) were identified by a dedicated large animal pharmacist, and 64.2% (145/226) of errors were identified and corrected before reaching the patient. Prescription/medication order errors (58.4% [132/226]) occurred significantly more often than errors in medication preparation (21.7% [49/226]; P < .001) and administration (19.6%; P < .001). Antibiotics (48.7% [110/226]) and NSAIDs (17.7% [40/226]) were the drug classes most involved in errors.

CLINICAL RELEVANCE

Most medication errors in this study occurred in the ordering/prescribing phase. This is similar to reports in human medicine, where standardized medication error reporting strategies exist. Developing and applying similar strategies in veterinary medicine may improve patient safety and outcome.

Free access
in Journal of the American Veterinary Medical Association

SUMMARY

Leukocytosis (34,600 wbc/μl of blood) was detected in an apparently healthy 7-day-old Holstein heifer. Analysis of blood samples obtained over the next 41 days revealed chronic progressive neutrophilia, which peaked at > 85% neutrophils and exceeded 100,000 wbc/μl. In vitro assessment of isolated blood neutrophils obtained from the heifer at 38 and 45 days of age revealed selected functional abnormalities. Endocytosis of immunoglobulin-opsonized Staphylococcus aureus and killing of this test organism by the calf’s neutrophils were significantly diminished, as were phagocytosis-associated superoxide generation, chemiluminescence activity, and myeloperoxidase-catalyzed iodination. Diminished H2O2 elaboration by the calf’s neutrophils was evident during ingestion of opsonized zymosan or on exposure to phorbol myristate acetate. Extracellular release (secretion) of elastase during ingestion of zymosan was also diminished, although total cell content of elastase was normal, compared with that of neutrophils from age-matched calves, and granular or other morphologic abnormalities of the calf’s neutrophils were not evident by ultrastructural examination. Abnormalities of random migration were inconsistently detected, and normal or high degree of antibody-dependent cytotoxicity or natural killing by the calf’s neutrophils was observed. Similar in vitro assessment of neutrophils obtained from the calf’s dam revealed no functional abnormalities. The calf died at 48 days of age, with persistent fever and chronic diarrhea, despite administration of antibiotics. Histologic examination at necropsy revealed large numbers of intravascular neutrophils in most tissues, including massive neutrophil sequestration in spleen. However, a striking lack of extravascular neutrophils was evident in inflamed submucosa adjacent to intestinal ulcers heavily contaminated with enteric microorganisms. Bone marrow examination revealed diffuse myeloid hyperplasia, but no other abnormalities.

The clinical and pathologic features in this calf were similar to those in previously reported human patients or Irish Setters with genetic deficiency of the CD11/CD18 leukocyte glycoprotein complex, thus prompting further postmortem evaluations. Results of immunoblot analyses of the neutrophil lysates of the heifer calf (isolated and stored prior to death) documented severe deficiency of Mac-1 (CD11b/CD18). Results of immunofluorescent analyses indicated substantially diminished (intermediate) amounts ofthe Mac-1 β subunit (CD18) on blood neutrophils of the calf's dam and sire and on neutrophils of 8 of 15 paternal half-siblings; findings were consistent with an autosomal recessive trait in the proband's kindred. Findings also indicate that genetic abnormalities of CD11/CD18 proteins may underlie the molecular pathogenesis of disease in this calf as well as other previously described examples of the granulocytopathy syndrome in Holstein cattle.

Free access
in American Journal of Veterinary Research

Abstract

OBJECTIVE

Referencing growing concerns over the recruitment and retention of faculty in academic veterinary medicine, the authors hypothesized that among surveyed veterinary residents and early-career faculty, work-life balance and workplace climate and culture are stronger motivators than financial considerations, regardless of demographic factors such as gender, race/ethnicity, and area of specialization.

SAMPLE

541 participants were included in data analysis.

METHODS

A mixed methods approach was utilized, incorporating both quantitative data and qualitative, free-text responses to better understand veterinary career choices by contextualizing factors associated with academic medicine.

RESULTS

Factors underpinning career-related decision-making were ranked by level of importance as (1) workplace environment/culture, (2) personal well-being/work-life balance, (3) salary and bonuses, (4) geographic location, (5) facilities and resources, (6) benefits, and (7) schedule flexibility. Desires for workload balance, schedule flexibility, support from leadership, and mentorship and collaboration were among the top themes of qualitative responses for both residents and early career faculty respondents. Factors influencing career decision-making for resident and early-career faculty are varied. Workplace environment, work-life balance, and schedule flexibility are areas that academic institutions can address and continue to improve and that are likely to positively impact entry into academia and the desire to stay.

CLINICAL RELEVANCE

This study sought to understand factors related to career decision-making and interest in academic veterinary medicine among residents and early-career faculty. Understanding these factors can support efforts to recruit and retain faculty in academic veterinary medicine.

Open access
in American Journal of Veterinary Research