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1.
Schmallenberg virus (SBV), a novel orthobunyavirus that rapidly spread throughout north-western Europe in 2011, caused congenital malformations in lambs and goat kids (Van den Brom et al., 2012) and newborn calves (Hoffmann et al., 2012). The impact of the SBV epidemic seemed limited however, in terms of the number of affected herds with malformed offspring (European Food Safety Authority, 2012b). Nevertheless, little is known with regard to the overall within-herd impact of SBV infection. The objective of the current study was to quantify the impact of the 2011 SBV epidemic on the productivity of dairy cattle in the Netherlands and the district of Kleve, Germany.  相似文献   
2.
The preparation and analysis of inorganic-organic polymer nanocomposites consisting of inorganic nanowires and multiwire "cables" in a random-coil organic polymer host is reported. Dissolution of inorganic (LiMo3Se3)n wires in a strongly coordinating monomer, vinylene carbonate, and the use of a rapid polymerization in the presence of a cross-linking agent produce nanocomposites without phase separation. Polymerization of dilute solutions yields a material containing mostly (Mo3Se3(-))n mono- and biwires, 6 to 20 angstroms in diameter and 50 to 100 nanometers long. Polymerization of more concentrated liquid crystalline solutions yields a nanocomposite containing oriented multiwire cables, 20 to 40 angstroms in diameter and up to 1500 nanometers long, that display optical anisotropy and electrical conductivity.  相似文献   
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In 1989, 220 Holstein Friesian cattle (212 heifers and eight bulls) were imported from Minnesota, USA, to form a closed dairy herd in Arab El-Aoumar, Assiut, Upper Egypt. In November 1996, some abnormal signs such as loss of weight, decreased milk yield, external lymphadenopathy and decreased appetite were observed on this farm. Serological screening by enzyme-linked immunosorbent assay revealed a seroprevalence of antibodies directed against bovine leukaemia virus (BLV) of 37.7% in cattle under 2 years old and of 72.8% in animals more than 2 years old. Diagnosis was confirmed by the detection of BLV proviral DNA using polymerase chain reaction with primers amplifying a fragment of the env gene. Out of 21 tested leucocyte fractions from individual animals, 15 were positive showing a BLV-specific amplicon of 444 base pairs. Analysis of the amplicons for restriction fragment length polymorphisms and DNA sequencing results allowed the isolates to be typed. Since this was the first recorded case of enzootic bovine leukosis in Upper Egypt, strict quarantine measures were adopted and all serologically positive animals in the herd were culled.  相似文献   
4.
A 6-year-old female Alaska Malamute dog was presented for evaluation of abdominal enlargement referred by a local veterinarian. On the history, the owner complained of chronic abdominal enlargement initiated more than 4 months ago, reduced appetite, occasional vomiting and general dullness. He also complained of greenish mucous intermittent vaginal discharge starting 10 days ago. The bitch was chronically treated with medroxiprogesterone acetate. A laparatomy was performed and fluid in the abdomen was found and aspirated during the surgery. Also a very fluid-filled distended uterus and a mass in the distal part of the left uterine horn were found. The mass was encapsulated by the omentum, but areas of necrosis and calcification were identified. Histopathological diagnosis was endometrial adenocarcinoma.  相似文献   
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The Friedrich-Loeffler-Institut, founded in 1910 by Friedrich Loeffler, the discoverer of the first animal virus, foot-and-mouth disease virus, is the oldest virological research facility in the world. Beyond viruses, its area of competence has significantly expanded since its foundation and now also covers bacterial, parasitic and prion diseases of livestock, poultry and aquatic animals. Presently located at four sites within Germany (Insel Riems, Jena,Tübingen,Wusterhausen) the tasks of the institute as delineated in the Animal Disease Act encompass research on infectious animal diseases including zoonoses, import/export examinations, epidemiological studies in case of outbreaks of notifiable animal diseases, acting as reference laboratory for notifiable animal diseases and nationwide quality management of diagnosis of notifiable animal diseases. It is obliged to publish and maintain up-to-date diagnostic regimes for notifiable animal diseases, and it publishes a yearly report on animal health in Germany. With the increasing importance of infectious diseases of animals, in particular those potentially harmful to man (zoonoses), the Friedrich-Loeffler-Institut will be moving into new facilities including laboratories and animal facilities up to the highest biosafety level at its main site Insel Riems on the occasion of its 100th anniversary.  相似文献   
8.
Some invasive wildlife species have the potential to act as additional host and vector species for parasitic and other infectious diseases. We used the raccoon dog (Nyctereutes procyonides), a carnivore species that has its origin in Asia, as an example to demonstrate biological and ecological prerequisites which enables an invasive species to occupy a new habitat permanently. Studies conducted during the last ten years identified a total of 23 endoparasites, two ectoparasites, six bacterial or protozoan species and five viruses, found in the Nyctereutes procyonoides ussuriensis subspecies in its newly occupied range or in N. procyonoides koreensis in its original range. Results of studies in Finland and Germany furthermore showed that biological characteristics of the raccoon dog make this carnivore an appropriate host or vector for a variety of parasites and infectious diseases. This may result in a growing importance of this invasive carnivore for the epidemiology of transmissible diseases in Germany. Especially with regard to zoonotic disease outbreaks, the raccoon dog should therefore be paid more attention in disease prevention and eradication strategies.  相似文献   
9.
Bovine neosporosis: immunoblot improves foetal serology.   总被引:5,自引:0,他引:5  
The purpose of the study is the comparative evaluation of the immunofluorescent antibody test (IFAT) and an immunoblot (IB) test for the examination of foetal fluids for specific antibodies against Neospora caninum. Peritoneal and pleural fluids as well as abomasal contents were analysed. The results of the serological examinations were compared to those obtained by histological, immunohistochemical, and PCR analysis of foetal tissues as well as to the results of maternal serological examinations. Fluids were used undiluted in the IB and reactions against six immunodominant antigens were recorded. When the recognition of at least two immunodominant antigens was regarded as positive, the agreement of the IB with other diagnostic methods was good to moderate as characterised by kappa-values of 0.76 (histology/immunohistochemistry), 0.69 (maternal serology) and 0.54 (PCR on foetal tissues). The IB results agreed better with the results of the other diagnostic methods than those of the IFAT. The higher relative sensitivity of the IB was regarded as the main reason for the better agreement. However, also the specificity of the IB was superior to that of the IFAT in relation to histology/immunohistochemistry, maternal serology and PCR.  相似文献   
10.
Various existing serological tests were compared with a standard panel of 523 sera in a multicentred study across Europe. Well characterised sera from animals that were experimentally or naturally infected with Neospora caninum as well as sera from cattle deemed uninfected with N. caninum were provided by the participants of the study and analysed in several commercial (CHEKIT Dr. Bommeli/Intervet, CIVTEST BOVIS NEOSPORA Hipra, Cypress Diagnostics C.V., Herd Check IDEXX, Mastazyme MAST Diagnostics, P38-ELISA Animal Welfare and Food Safety GmbH (AFOSA)) as well as in-house assays (five ELISAs and one IFAT). Most tests showed a high level of agreement in the interpretation of the test results (positive or negative). A further distinct increase in agreement between tests was obtained after the application of standardised cut-offs offered by a two-graph receiver operating characteristic analysis. This procedure allows a standardised interpretation of results obtained with different tests used in independent, parallel seroepidemiological studies.  相似文献   
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