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41.
In this study a Salmonella Typhimurium infection model in swine was used in order to investigate the influence of pre-mortal stress induced by long time period transportation on the re-activation of Salmonella in experimentally infected pigs. Salmonella free pigs were exposed to a highly virulent strain of Salmonella Typhimurium DT104 by direct intragastrical administration. Clinical parameters were monitored and the shedding rate in faeces was qualitatively and quantitatively determined by standard bacteriological procedures for 21 days. The distribution of the challenge organism in 14 different internal organs of transported and nontransported animals was determined. All infected animals developed clinical signs of salmonellosis 12 to 24 hours post infection. About 88 to 100% of the fecal samples were culture-positive up to post exposure day 6, and then varied from 71 to 92% until slaughter, respectively. At necropsy S. Typhimurium was recovered most frequently from caecum and ileocolic lymph nodes (83%), colon (79%), palatine tonsils (71%) and mandibular lymph nodes (62.5%). A negative impact of transportation stress on the shedding rate and the general condition of the animals was observed.  相似文献   
42.
Echinostomiasis is a food-borne, intestinal, zoonotic, snail-mediated helminthiasis caused by digenean trematodes of the family Echinostomatidae with seven species of the genus Echinostoma infecting humans or domestic and wildlife animals. Echinostoma paraensei is a peristomic 37-collar-spined echinostome belonging to the “revolutum group”.  相似文献   
43.
OBJECTIVES: To determine the distribution of blood types and to estimate the proportion of matings at risk for neonatal isoerythrolysis in non-pedigree domestic cats. METHODS: The present survey determined the frequency of blood types in 301 cats from four distinct regions of Turkey. Ethylenediaminetetraacetic acid-anticoagulated blood samples were typed by simple tube and slide agglutination assays. Serum obtained from type B cats and an anti-B solution, prepared with Triticum vulgaris, were used to determine type A and type B blood, respectively. RESULTS: Of the 301 cats typed, 220 had type A blood, 74 had type B and seven had type AB. There was a significant difference (P<0.01) between the locations of the cats, with fewer type B cats in the eastern than in the western parts of Turkey. Risk for the development of neonatal isoerythrolysis due to A-B mismatch was estimated to be 18.6 per cent. CLINICAL SIGNIFICANCE: The overall type B frequency in Turkish domestic cats is high. Thus, untyped transfusions in these cats carry a high risk of life-threatening acute haemolytic transfusion reactions and neonatal isoerythrolysis. It is therefore strongly recommended that blood typing be performed before breeding or transfusing in order to minimise blood type incompatibility risks.  相似文献   
44.
The effect of a concentration of crude protein of 170 or of 227 g/kg in the ration of chicken from the 1st to the 14th day after hatching on biochemical values of the liver, the M. pectoralis superficialis and the serum was analysed. The significance of developmental investigations in domestic animals under normal and pathological conditions is discussed.  相似文献   
45.
Ultrasonography was used to compare adhesions induced by two different methods of gastropexy in 16 dogs. An incisional gastropexy technique was used in eight dogs (group 1) and a 'modified' gastropexy technique in the remaining eight (group 2). The length and thickness of the gastropexy and the peristaltic activity of the stomach were measured ultrasonographically and compared between groups. Measurements for the two groups were taken in the early postoperative interval (two to four days), intermediate postoperative interval (eight to 20 days) and late postoperative interval (57 to 79 days). Both techniques were equally successful in forming permanent adhesions at two months postoperatively and there was no recurrence of gastric dilatation and volvulus. The length and thickness of the gastropexy were similar for both groups at two months postoperatively and there were no surgical complications with either technique. The modified gastropexy provides a technique that can easily be performed by a single surgeon , with no increased operative time or duration of anaesthesia, and with the formation of a permanent adhesion.  相似文献   
46.
The goal of the present study was to examine the musculophrenic vein of 29 healthy Swiss Braunvieh cows using colour-Doppler sonography to determine vessel morphology and diameter, and blood flow velocity. The hair over the reticular region was clipped, and the left musculophrenic vein was examined before and 10 min after sedation using 0.03 mg/kg xylazine. The musculophrenic vein appeared as a vessel with a diameter of 0.5–1.1 cm located in the diaphragmatic musculature. The spectral display was a broad band structure with a wave-like shape. The Doppler measurement point was 1.5–2.7 cm from the body surface. The diameter of the vein and the blood flow velocity did not differ significantly before and after sedation. Before sedation, the mean diameter (±SD) of the musculophrenic vein was 0.7 (0.2) cm, the maximum blood flow velocity 90.2 (38.6) cm/s, the mean blood flow velocity 60.4 (22.3) cm/s and the minimum blood flow velocity 41.4 (24.2) cm/s. There were significant correlations (r = 0.45–0.90) between blood flow velocity before and after sedation and between minimum, maximum and mean blood flow velocities.  相似文献   
47.
AIMS: To analyse the performance characteristics (sensitivity/specificity) of two enzyme-linked immunosorbent assays (ELISA) against the indirect fluorescent antibody test (IFAT). METHODS: A total of 1199 sera were tested in two ELISAs and the IFAT and results analysed utilising software that performed a receiver-operating characteristic (ROC) analysis. RESULTS: Sensitivity and specificity for the two ELISAs were calculated for a range of different cut-offs. Minimal misclassification was achieved at cut-offs that, in the case of the Central Animal Health Laboratory (CAHL)-ELISA were in line with previously published cut-off values. In the case of the IDEXX-ELISA lower cut-off values than suggested by the manufacturer were calculated. CONCLUSIONS: ROC-analysis resulted in optimised, as compared to the IFAT, cut-off thresholds for the CAHL and IDEXX-ELISA which can be further adjusted depending on the purpose of the investigation.  相似文献   
48.
49.
Introduction: Cell‐based vaccine strategies using dendritic cells as cellular adjuvant have entered phase III trials in humans and have been found to be safe, feasible, and potentially efficacious. Canine patients are generally smaller than adult human patients, which makes production of canine dendritic cell (DC) vaccines problematic, given patient size and the small number of available DC precursors. Here we describe feasibility studies of a novel cell‐based vaccine strategy which uses CD40‐activated B‐cells (CD40‐B) loaded with RNA. This strategy is based on our observations that RNA‐transfected human CD40‐B can drive anti‐tumor T cell responses. One advantage of using CD40‐B cells is the ability to expand this cell population ex vivo, allowing for the numbers of cells required for therapeutic vaccines. Methods: Twenty milliliters of blood were drawn from 6 normal dogs and 5 canine lymphoma patients. Peripheral blood mononuclear cells were separated by Ficoll centrifugation. Culture conditions for B cell activation were optimized using CD40‐ligand, canine IL‐4, and Toll‐like receptor stimulus with CpGoligodinucleotides (ODN). Cyclosporine was added to eliminate peripheral T lymphocytes. Proliferation and activation of CD40‐B cells were demonstrated by CFSE dilution of B cells quantified by flow cytometry. Gene transfer was achieved by mRNA electroporation. Results: Marked in vitro stimulation and proliferation of canine peripheral B cells were achieved with soluble trimeric CD40L, canine IL‐4, and ODN. CD40‐B cells showed dramatic upregulation of MHC class II molecules and CD21 (B‐cell activation marker). After two weeks in culture, cells were negative for CD3 and CD4. Canine CD40‐B cells were efficiently transfected with mRNA, with >60% of CD40‐B expressing green fluorescent protein after GFP mRNA electroporation. Conclusion: RNA‐transfected CD40‐B cells can be efficiently generated from normal and tumor‐bearing dogs. These results provide rationale to test tumor RNA‐transfected CD40‐B as a novel therapeutic approach to treating canine malignancies. Clinical trials in canine lymphoma have been proposed.  相似文献   
50.
Oesophageal strictures in 2 horses with chronic recurrent oesophageal obstruction or choke was diagnosed by endoscopy and contrast radiography. Balloon dilation of the strictures was performed under endoscopic and fluoroscopic guidance. Follow‐up endoscopic and radiological examinations performed 6 weeks after the procedure showed clear dilation of the strictures. Both horses did not have any recurrence during follow‐up periods of 10 and 12 months.  相似文献   
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