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Chae C Cheon DS Kwon D Kim O Kim B Suh J Rogers DG Everett KD Andersen AA 《Veterinary pathology》1999,36(2):133-137
Gnotobiotic piglets were inoculated intralaryngeally with swine Chlamydia trachomatis strain R33 or orally with swine C. trachmatis strain R27. Archived formalin-fixed, paraffin-embedded tissues from piglets euthanatized 4-7 days postinoculation were examined by in situ hybridization for C. trachomatis nucleic acid using a nonradioactive digoxigenin-labeled DNA probes that targeted specific ribosomal RNA or omp1 mRNA molecules of the swine C. trachomatis strains. Positive hybridization signals were detected in bronchial epithelial cells, bronchiolar epithelial cells, pneumocytes, alveolar and interstitial macrophages, and jejunal and ileal enterocytes. Chlamydia-infected cells had a strong signal that was confined to the intracytoplasmic inclusions. Positive hybridization signals were not detected in tissue sections from an uninfected control piglet or in C. psittaci-infected sheep placenta. The morphology of host cells was preserved despite the relatively high temperature required in parts of the incubation procedure. The data indicate that in situ hybridization can be used to detect swine C. trachomatis in formalin-fixed, paraffin-embedded tissue specimens. 相似文献
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Freytag TL Liu SM Rogers QR Morris JG 《Journal of animal physiology and animal nutrition》2003,87(1-2):42-51
High concentrations of retinoids occur in some commercial cat food formulations as a result of the use of animal liver as an ingredient. Our objective was to study the teratogenic potential of dietary vitamin A in cats. We investigated the incidence of birth defects in kittens of queens given diets with retinyl acetate concentrations of 6000, 306000, or 606000 retinol equivalents (RE)/kg diet (control, 306K, or 606K groups, respectively) for approximately 3 years [1 RE=1 micro g retinol=3.3 International Units (IU)]. Each group comprised 12-15 age-matched, nulliparous domestic short-haired queens that were exposed to toms. There were a total of 396 kittens born in 97 litters. Pregnancy rate, number of kittens per gestation and gestations per year were not significantly different among treatment groups. A total of 2, 5 and 11 malformed kittens occurred in the control, 306K and 606K groups, respectively. Malformations included cleft palate, cranioschisis, foreshortened mandible, stenotic colon, enlarged heart and agenesis of the spinal cord and small intestine, which are typical foetal defects consistent with ingestion of excess retinoids in other species. This study demonstrated that a concentration of 306000 RE/kg diet has a potential for causing birth defects in the kittens. 相似文献
15.
Fascetti AJ Reed JR Rogers QR Backus RC 《Journal of the American Veterinary Medical Association》2003,223(8):1137-1141
OBJECTIVE: To determine signalment, history, clinical signs, blood and plasma taurine concentrations, electrocardiographic and echocardiographic findings, treatment, and outcome of dogs with low blood or plasma taurine concentrations and dilated cardiomyopathy (DCM). DESIGN: Retrospective study. ANIMALS: 12 client-owned dogs with low blood or plasma taurine concentrations and DCM. PROCEDURE: Medical records were reviewed, and clinical data were obtained. RESULTS: All 12 dogs were being fed a commercial dry diet containing lamb meal, rice, or both as primary ingredients. Cardiac function and plasma taurine concentration improved with treatment and taurine supplementation. Seven of the 12 dogs that were still alive at the time of the study were receiving no cardiac medications except taurine. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that consumption of certain commercial diets may be associated with low blood or plasma taurine concentrations and DCM in dogs. Taurine supplementation may result in prolonged survival times in these dogs, which is not typical for dogs with DCM. Samples should be submitted for measurement of blood and plasma taurine concentrations in dogs with DCM, and taurine supplementation is recommended while results of these analyses are pending. 相似文献
16.
McKenna SL Barkema HW McClure JT Rogers LA 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(4):312-313
A 2-year-old, purebred Holstein heifer with exercise intolerance and cardiovascular compromise was diagnosed at postmortem with tetralogy of Fallot, which typically results in death within a few months of life. Survival past the age of 2 was unexpected. The concurrent endocarditis of the pulmonic valve is discussed. 相似文献
17.
Foster AP Littlewood JD Webb P Wood JL Rogers K Shaw SE 《Veterinary immunology and immunopathology》2003,93(1-2):51-60
Atopic dermatitis in dogs is a common allergic skin disease that affects substantial numbers of dogs in the UK. The purpose of this study was to compare the results of an intradermal test (IDT) and an in vitro test in a large cohort of dogs. Dogs were intradermal tested with Greer allergens (Greer Labs Inc, Lenoir, NC, USA) using standard techniques. At the same time blood samples were drawn and submitted for evaluation by ELISA using the ALLERCEPT Definitive Allergen Panels for allergen-specific IgE, a commercial assay that uses a biotinylated recombinant extracellular domain of the high affinity Fc-epsilon receptor alpha chain protein (Fcepsilon RIalpha). The allergens used in the two tests included grass, tree and weed pollens, moulds, flea saliva/whole flea extract and house dust mite species. The optical density readings from the ELISA for each allergen were compared with the results of the IDT for 265 dogs. The prevalence of positive reactions in the ELISA was equal to or greater than the results of the IDT in the case of almost all of the allergens, but two notable exceptions were the house dust mites Dermatophagoides farinae and Dermatophagoides pteronyssinus. These two allergens were the most common positive reactions by IDT (prevalence D. farinae 78.9%, D. pteronyssinus 66.4%). The results of the two tests were significantly different (McNemar's test, P<0.05) for 16 of the 22 allergens. The sensitivities of the ELISA compared to the IDT (where there were more than 3 dogs with positive reactions in both tests) varied between 19.3 and 77.1% (D. pteronyssinus 19.3% and D. farinae 67.9%) and the specificities varied between 64.2 and 96.6% (D. pteronyssinus 96.6% and D. farinae 89.3%). 相似文献
18.
Alley MR Connolly JH Fenwick SG Mackereth GF Leyland MJ Rogers LE Haycock M Nicol C Reed CE 《New Zealand veterinary journal》2002,50(5):170-176
AIM: This study reports an outbreak of salmonellosis due to S. Typhimurium DT160 which caused extensive mortality in wild birds and enteric disease in humans in New Zealand during the winter and spring months of the year 2000. METHODS: Necropsies were performed and microbiological examinations undertaken on wild birds from populations in which mass mortality was reported, and on captive indigenous birds which died suddenly during the winter and spring of 2000. Affected tissues were examined histologically and isolates of S. Typhimurium were phage typed and examined using pulsedfield gel electrophoresis (PFGE). Isolates of S. Typhimurium obtained from cases of human enteric disease which occurred during these months were phage typed, examined using PFGE and compared with the bird isolates. RESULTS: Central and northern areas of the South Island and the southern North Island were worst affected with die-offs of several hundreds of sparrows and other birds reported in rural areas. Mortalities reached a peak in winter (July-August) 2000 and decreased to small numbers during the spring and early summer. The birds usually died of an acute septicaemia with multifocal necrotising lesions in the liver and spleen. Human cases throughout the country increased gradually over the same period. Isolates from birds, livestock and humans examined using PFGE were indistinguishable from one another. CONCLUSION: This strain of Salmonellahas emerged as a major cause of septicaemia in wild birds in New Zealand. Because of the close association between house sparrows (Passer domesticus) and humans, the organism also poses a serious zoonotic risk. The possibility that the infection may spread to involve indigenous species needs investigation. 相似文献
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Baldwin CL Sathiyaseelan T Naiman B White AM Brown R Blumerman S Rogers A Black SJ 《Veterinary immunology and immunopathology》2002,87(3-4):251-259
Bovine peripheral blood gammadelta T cells have been evaluated for effector function (IFN-gamma production) and clonal expansion in a variety of systems including following activation by mitogens, IL-12, and stimulation, through the T cell receptor (TCR) with anti-CD3 monoclonal antibody (mAb), a cell-bound molecule and a soluble antigenic extract. To evaluate cell division, carboxyfluorescein succinimidyl ester (CFSE) loading of cells and flow cytometric analysis were used, while IFN-gamma production was evaluated by intracytoplasmic staining. It was found that bovine gammadelta T cells produced IFN-gamma and clonally expanded when stimulated through the TCR/CD3 complex by a cell-associated autologous molecule on monocyte, by bacterial components following in vivo sensitization of gammadelta T cells with a leptospira vaccine or by anti-CD3 mAb. In addition, gammadelta T cells were activated efficiently for effector function but not clonal expansion by culturing with IL-12. In contrast, stimulation by Con A or PMA/ionomycin induced efficient replication but only low level IFN-gamma production which was not enhanced by the presence of IL-12. In several systems the amount of IFN-gamma produced per cell by gammadelta T cells was less than that produced by CD4 T cells in the same cultures. 相似文献