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1.
A young intact female dog was presented with urinary incontinence. Abdominal ultrasound revealed the presence of hyperechoic linear structures within the cranial vagina suggestive of foreign material. A computed tomography (CT) retrograde vaginourethrogram demonstrated the presence of a fistulous tract between the urethra and vagina. A presumptive diagnosis of urethrovaginal fistula due to migration of foreign material was made. The grass awn was removed with vaginoscopic‐guided retrieval. Fourteen days later, surgical repair of the fistula and an ovariohysterectomy were done. This case report emphasizes the usefulness of CT for diagnosis and precise anatomical localization of genitourinary tract fistulas.  相似文献   
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OBJECTIVE: To develop a blocking ELISA for detection of bovine leukemia virus (BLV) antibodies that is comparable to a radioimmunoprecipitation (RIP) assay, to evaluate use of this ELISA for identification of BLV-infected herds, and to develop a polymerase chain reaction (PCR) assay for direct diagnosis of infection with BLV. SAMPLE POPULATION: Serum samples and pooled bulk-tank milk samples from cattle. PROCEDURE: The blocking ELISA was developed, using BLV gp51 as antigen, captured by a selected bovine polyclonal serum. A nested PCR was conducted with primers specific for a segment of the pol region of the BLV genome. RESULTS: Sensitivity and specificity of the ELISA were comparable to those of the RIP assay. Use of the ELISA on pooled milk samples allowed identification of herds in which prevalence of BLV infection among lactating cows was as low as 2.5%. Pooled milk samples from BLV-free herds did not react in the ELISA. All cattle that had positive results for the nested PCR had BLV antibodies, but cattle with consistantly low antibody titers required examination of sequential DNA samples to detect viral sequences. None of the 63 antibody-negative cattle had positive results for the PCR. CONCLUSIONS AND CLINICAL RELEVANCE: This ELISA is a highly specific and sensitive assay for the detection of BLV antibodies in serum and milk samples of cattle. Examination of pooled milk samples with the ELISA provides a reliable, practical, and economic procedure for identification of BLV-infected herds. The nested PCR also constitutes a specific procedure for direct diagnosis of infection with BLV.  相似文献   
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The community composition and structure of helminths of Pipistrellus pipistrellus (Schreber, 1774) from two widely separated Spanish localities, El Saler (n = 42) and the San Pedro pothole (n = 34), were determined and compared. Five species of trematodes, Plagiorchis (Plagiorchis) sp., Lecithodendrium (Lecithodendrium) linstowi Dollfus, 1931, Prosthodendrium (Prosthodendrium) sp., Pycnoporus heteroporus (Dujardin, 1845) and Parabascus semisquamosus (Braun, 1900), and one species of cestode, Hymenolepis pipistrelli López-Neyra, 1941, were found. The two bat populations harboured the same helminth species and showed the same trematode dominance, but the most important differences between the two helminth community structures were attributable to L. (L.) linstowi and H. pipistrelli. The mean species richness in the two localities was not significantly different. The mean number of helminth species per infected bat, mean infracommunity abundance and mean infracommunity diversity showed significant differences between both localities. The number of helminths per bat in both populations displayed an aggregated distribution. Results indicate that the different characteristics of the P. pipistrellus foraging area in both localities are important in determining the composition and structure of helminth communities in this bat species. This is the first study of a Palaearctic bat helminth community.  相似文献   
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ABSTRACT Isolates of the Diaporthe/Phomopsis (D/P) complex were collected in the main soybean producing area of Argentina during the 1996-97, 1997-98, and 1998-99 growing seasons. Twenty-three morphologic characters related to type of colonies, stroma, pycnidia and conidia, presence of perithecia, and asci length were studied by principal component analysis (PCA). Genomic DNA were analyzed by the random amplified polymorphic DNA (RAPD) technique. From both studies, 18 isolates were identified as D/P complex and grouped in four major taxa: (i) Diaporthe phaseolorum var. meridionalis, (ii) D. phaseolorum var. caulivora, (iii) D. phaseolorum var. sojae, and (iv) Phomopsis longicolla. In addition to distinguishing interspecific and intraspecific variability, molecular markers allowed the detection of differences among isolates within the same variety. Pathogenicity was assayed in the greenhouse, by the toothpick method, inoculating the D/P isolates to soybean genotypes carrying different resistance genes (Rdc1, Rdc2, Rdc3, and Rdc4) against soybean stem canker (SSC). Pathogenic analysis distinguished two main groups: (i) the SSC-producing isolates, including D. phaseolorum var. meridionalis and D. phaseolorum var. caulivora, and (ii) the non-SSC-producing isolates, including D. phaseolorum var. sojae and P. longicolla. Cultivar RA-702 (susceptible control) was compatible with both D. phaseolorum var. meridionalis and D. phaseolorum var. caulivora isolates; meanwhile, Tracy-M (Rdc1 and Rdc 2 genes) was incompatible with D. phaseolorum var. meridionalis but compatible with D. phaseolorum var. caulivora isolates. The fact that Rdc1 and Rdc2 together (as in Tracy-M) confer an almost immune reaction to all assayed isolates of D. phaseolorum var. meridionalis but were ineffective against the D. phaseolorum var. caulivora isolates evaluated suggests that the virulence or avirulence genes in D. phaseolorum var. meridionalis and D. phaseolorum var. caulivora are different. Moreover, physiological races of D. phaseolorum var. meridionalis were detected by using differential soybean genotypes carrying distinct single Rdc genes. As far as we know, this is the first report on the existence of physiological races of D. phaseolorum var. meridionalis in South America. Selective pressure due to deployment of resistant host cultivars may have changed the frequency of the virulence or avirulence genes within the population of D. phaseolorum var. meridionalis. On the whole, our results show that pathogenic variability of D. phaseolorum in the core soybean-producing area of Argentina is higher than previously recognized.  相似文献   
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Twenty-six dogs with parasitologically confirmed leishmaniasis and abnormalities of gait were studied to determine the most common radiological patterns of bone and joint lesions. The clinical findings included either lameness, joint pain and crepitation, soft tissue swelling and/or muscle atrophy. Bone lesions were observed radiographically in 12 of the 26 dogs; the radius and ulna were affected in seven, the tibia in six and the femur in six. Joint lesions were observed radiographically in 15 of the 26 dogs; the carpus and stifle were affected in all 15, and the tarsus in nine. There was a tendency for the bones and joints to be affected bilaterally. The radiographic patterns observed were different in the long bones and the joints. In the long bones, the most common pattern was periosteal and intramedullary proliferation, involving the diaphyses and related to the nutrient foramen; in the joints, two patterns, either non-erosive or erosive polyarthritis with soft-tissue swelling, were observed. The changes observed in the synovial fluid were associated in most cases with osteolytic lesions. However, Leishmania organisms were identified in the synovial fluid from joints without bony radiographic changes.  相似文献   
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An eight-month-old Pekingese bitch with urinary incontinence was found to have three congenital anomalies of the urinary tract: left renal agenesis, bilateral ectopic ureters with a left cranial blind-ending ureter, and urinary bladder hypoplasia. The diagnoses were made by retrograde vaginourethrography, excretory urography, ultrasonography and duplex Doppler ultrasonography. Although urological anomalies associated with renal agenesis have been frequently observed, a cranial blind-end ectopic ureter has not, to the authors' knowledge, been described in the bitch. The dog was managed medically with a restricted protein diet because of a compromised unilateral kidney with hydronephrosis and hydroureter.  相似文献   
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Foot-and-mouth disease virus   总被引:11,自引:0,他引:11  
Foot-and-mouth disease virus (FMDV) is an aphthovirus of the family Picornaviridae and the etiological agent of the economically most important animal disease. As a typical picornavirus, FMD virions are nonenveloped particles of icosahedral symmetry and its genome is a single stranded RNA of about 8500 nucleotides and of positive polarity. FMDV RNA is infectious and it replicates via a complementary, minus strand RNA. FMDV RNA replication is error-prone so that viral populations consist of mutant spectra (quasispecies) rather than a defined genomic sequence. Therefore FMDV in nature is genetically and antigenically diverse. This poses important challenges for the diagnosis, prevention and control of FMD. A deeper understanding of FMDV population complexity and evolution has suggested requirements for a new generation of anti-FMD vaccines. This is relevant to the current debate on the adequacy of non-vaccination versus vaccination policies for the control of FMD.

Résumé

Le virus de la fièvre aphteuse est un aphtovirus de la famille des Picornaviridae et l'agent de la maladie animale la plus importante sur le plan économique. En tant que picornavirus typique, le virus de la fièvre aphteuse est nu, sous forme d'icosaèdre et son génome comprend un acide ribonucléique monobrin avec environ 8500 nucléotides et une polarité positive. L'acide ribonucléique de ce virus est infectieux et il se réplique par l'intermédiaire d'un brin d'ARN moins, complémentaire. La réplication de l'acide nucléique de ce virus conduit à des erreurs, de telle sorte que les populations virales comprennent un ensemble de mutants (quasi espèce) plutôt qu'une séquence génomique bien définie. Par suite, le virus de la fièvre aphteuse est génétiquement et antigéniquement varié. Ceci entraîne des difficultés importantes pour le diagnostic, la prévention et la maîtrise de la fièvre aphteuse. Une connaissance plus approfondie de la complexité et de l'évolution de la population de ce virus a conduit à des besoins pour une nouvelle génération de vaccines aphteux. Ceci est lié au débat actuel sur le choix d'une politique de vaccination ou de non-vaccination dans la lutte contre la fièvre aphteuse.  相似文献   

10.
The effects of including lyophilised whole yeast, Saccharomyces cerevisiae, in the diet on the seabream innate immune response were investigated. Gilthead seabream (Sparus aurata L.) specimens were fed four different diets for 4 weeks: a commercial diet as control and the same diet supplemented with 1, 5 or 10 g/kg yeast. After 1, 2 and 4 weeks, serum complement titres, as a humoral parameter, and phagocytic, respiratory burst, myeloperoxidase and natural cytotoxic activities of head-kidney leucocytes, as cellular parameters, were evaluated. The results showed that yeast supplements enhanced all the latter responses, but not the humoral response. This enhancement was dose-dependent except for the cytotoxic activity that was only stimulated by the lower dose of yeast assayed. As yeast cell walls are able to enhance the seabream cellular innate immune response, these results support the possible use of whole yeast as natural inmunostimulants in common fish diets.  相似文献   
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