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CASE DESCRIPTION: 4 North American porcupines were evaluated because of diarrhea or neutropenia (or both) that developed after treatment with fenbendazole for intestinal parasites. CLINICAL FINDINGS: Complete blood cell count abnormalities included severe neutropenia in all affected porcupines and mild anemia in some of them. In 2 porcupines, postmortem findings included bone marrow hypoplasia and intestinal crypt cell necrosis. TREATMENT AND OUTCOME: Affected porcupines received supportive care including fluid supplementation and broad-spectrum antimicrobials. The 2 surviving animals recovered after 9 to 33 days of treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Fenbendazole is an anthelminthic that may be used in an extralabel manner for the treatment of intestinal parasitism in wildlife species. The drug inhibits mitosis and can affect rapidly dividing cell lines, such as those in the bone marrow and intestinal crypt mucosa. Fenbendazole may not be an appropriate anthelminthic choice in North American porcupines.  相似文献   
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During an on-going amphibian ecology study, a free-ranging American bullfrog (Rana catesbeiana) metamorph was captured in a pitfall trap adjacent to a constructed farm pond at the Plateau Research and Education Center (PREC) on the Cumberland Plateau near Crossville, Tennessee, USA. Grossly, the right eye was approximately 50% the size of the left. Stereo and light microscopic examination revealed two granulomas within the orbit. Electron microscopic examination revealed virus particles scattered throughout one structure but mostly aggregated toward the center. Subsequent PCR and sequencing (GenBank accession Number EF175670) confirmed frog virus 3 (FV3). This represents the first report of a malformation in an anuran associated with FV3.  相似文献   
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Gene frequencies of RBC antigens were determined in Holsteins and Colombian (criollas) cattle living at 3,000 m, and in cattle descended from fighting bulls (Vacas de lidia) living at 2,500 m. These frequencies were compared with those of Holsteins, cattle native to Florida (scrub cattle), longhorns, and native cattle from Brazil (caracu cattle) living at sea level. The criollas, Vacas de lidia, scrub cows, longhorns, and caracu are descendants of original Iberian stock introduced to the Americas. We found that despite common ancestry (scrub cattle, long-horns, criollas, and caracu), genetic differences may have been derived through years of demographic isolation. The most remarkable blood-group differences were found in the high prevalence of the B system phenogroup (heritable group of antigenic factors) BQA'G'34 in the Vacas de lidia, and of the S system phenogroup U1H' in these cattle and in caracu. Furthermore, the gene frequencies differed in the Holsteins maintained at moderately high altitude (descended from Holsteins kept at sea level), and may have been reflective of the need to adapt to moderately high altitude and chronic hypoxemic conditions. Blood group polymorphism was found in all groups of cattle, although it was reduced in the Vacas de lidia, possibly because their breeding has been carefully controlled and they appear to be highly inbred.  相似文献   
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The effects of zearalenone (F-2), ochratoxin A and T-2 toxins on the synthesis of DNA, RNA and proteins in mouse L cells were studied. F-2 toxin inhibited protein synthesis to a lesser extent than DNA and RNA synthesis, whereas ochratoxin A inhibited the synthesis of each equally. Exposure to the toxins for 24 hours relatively reduced the synthetic ability of the cells. T-2 toxin inhibited protein and DNA synthesis in parallel but RNA synthesis to a lesser extent. Enhanced incorporation of tritiated thymidine was found when L cells were exposed to 0.4 to 0.016 ng of T-2 toxin ml-1 for 24 hours.  相似文献   
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