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151.
A captive, 20-year-old female elk (Cervus elaphus nelsoni) euthanized due to progressive lameness and weight loss was presented to Colorado State University Veterinary Diagnostic Laboratory for postmortem examination. Within the uterus there was a poorly demarcated, multilobulated mass measuring 10 cm in diameter. Histologically the tumor was an adenocarcinoma. Histologic examination of the ovaries revealed unilateral metastasis. A focal, 1-cm diameter adenocarcinoma was identified within the abomasum; this tumor was histologically distinct from the neoplasm found in the uterus and ovary. Although this elk had a history of experimental reproductive treatments, including leuprolide, gonadotropin-releasing hormone vaccine, and Brucella abortus vaccination, it was most likely that both tumors represent spontaneous, independent neoplastic transformations and were unrelated.  相似文献   
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OBJECTIVE: To identify risk factors associated with development of pyothorax in cats, assess survival rates for cats that are treated, determine prognostic indicators, and determine recurrence rates. DESIGN: Retrospective study. ANIMALS: 80 cats with pyothorax and 212 control cats. PROCEDURE: History; month of evaluation; physical examination findings; results of hematologic, serum biochemical, and retrovirus testing; radiographic findings; outcome; recurrence rate; and necropsy findings were recorded. For control cats, age, sex, breed, indoor versus outdoor status, vaccination history, and single- versus multi-cat household status were recorded. RESULTS: Cats from multi-cat households were 3.8 times as likely (95% confidence interval, 1.9 to 8.2) to develop pyothorax, compared with cats from single-cat households. Indoor or outdoor status was not a risk factor. Cats with pyothorax were significantly younger (mean, 3.83 +/- 3.43 years) than controls (mean, 5.62 +/- 5.27 years). Nonsurvivors had significantly lower heart rates than survivors. Hypersalivation was significantly more common in nonsurvivors (11/39; 26.8%) than survivors (1/39; 3%). Overall, 48.8% (39/80) of cats survived. When cats that were euthanatized without treatment were excluded from analyses, the survival rate was 66.1% (39/59). Pyothorax recurred in 1 of 17 cats for which follow-up information was obtained. CONCLUSIONS AND CLINICAL RELEVANCE: Cats with pyothorax that received treatment had a fair to good prognosis, with low recurrence rates in survivors. Hypersalivation and low heart rate were associated with worse clinical outcome. Cats with pyothorax were likely to come from multi-cat households.  相似文献   
155.
OBJECTIVE: To estimate herd-level sensitivity (HSe), specificity (HSp), and predictive values for a positive (HPVP) and negative (HPVN) test result for several testing scenarios for detection of tuberculosis in cattle by use of simulation modeling. SAMPLE POPULATION: Empirical distributions of all herds (15,468) and herds in a 10-county area (1,016) in Michigan. PROCEDURE: 5 test scenarios were simulated: scenario 1, serial interpretation of the caudal fold tuberculin (CFT) test and comparative cervical test (CCT); scenario 2, serial interpretation of the CFT test and CCT, microbial culture for mycobacteria, and polymerase chain reaction assay; scenario 3, same as scenario 2 but specificity was fixed at 1.0; and scenario 4, sensitivity was 0.9 (scenario 4a) or 0.95 (scenario 4b), and specificity was fixed at 1.0. RESULTS: Estimates for HSe were reasonably high, ranging between 0.712 and 0.840. Estimates for HSp were low when specificity was not fixed at 1.0. Estimates of HPVP were low for scenarios 1 and 2 (0.042 and 0.143, respectively) but increased to 1.0 when specificity was fixed at 1.0. The HPVN remained high for all 5 scenarios, ranging between 0.995 and 0.997. As herd size increased, HSe increased and HSp and HPVP decreased. However, fixing specificity at 1.0 had only minor effects on HSp and HPVN, but HSe was low when the herd size was small. CONCLUSIONS AND CLINICAL RELEVANCE: Tests used for detecting cattle herds infected with tuberculosis work well on a herd basis. Herds with < approximately 100 cattle should be tested more frequently or for a longer duration than larger herds to ensure that these small herds are free of tuberculosis.  相似文献   
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OBJECTIVE: To determine risk factors associated with Cryptococcus gattii infection in dogs and cats residing on Vancouver Island in British Columbia, Canada. DESIGN: Matched case-control study. ANIMALS: 20 dogs and 29 cats with C gattii infection and matched controls. PROCEDURE: Dogs and cats with a confirmed or probable diagnosis of cryptococcosis resulting from infection with C gattii were enrolled by veterinarians, and owners completed a questionnaire designed to obtain information pertaining to potential risk factors for the disease. Owners of matched control animals were also interviewed. Odds ratios and 95% confidence intervals or paired t tests were calculated to determine significant associations. RESULTS: Animals were enrolled during 2 noncontiguous periods in August 2001 to February 2002 (8 dogs and 9 cats enrolled) and May to December 2003 (12 dogs and 20 cats enrolled). Risk factors significantly associated with development of cryptococcosis included residing within 10 km of a logging site or other area of commercial soil disturbance, above-average level of activity of the animal, travelling of the animal on Vancouver Island, hunting by the animal, and owners hiking or visiting a botanic garden. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that dogs and cats that were active or that lived near a site of commercial environmental disturbance had a significantly increased risk of developing C gattii infection. Veterinarians should communicate these risks to owners in context because cryptococcosis was an uncommon disease in this population.  相似文献   
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