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Zusammenfassung Vor drei Jahren setzten in der Bundesrepublik Deutschland amtliche Bestrebungen ein, die schwierigen Aufgaben der biologischen Schädlingsbekämpfung zu sichten und die vordringlichsten von ihnen einer Lösung zuzuführen. Die Schriftleitung erachtete es für notwendig, einen Überblick über die Aufgaben und den Stand der Arbeiten zu vermitteln, und hat daher den Verfasser um einen Bericht über die in der Bundesrepublik laufenden Untersuchungen. In seiner Eigenschaft als deutscher Fachvertreter und zugleich Vizepräsident der internationalen Kommission für biologische Bekämpfung (CILB) ist Herr Regierungsrat Dr. J. Franz unserem Wunsche nachgekommen, in kurzen Zügen auch auf die internationalen Beziehungen und Zusammenarbeit einzugehen.  相似文献   
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The use of conventional battery cages for hens will be prohibited in Germany in 2007. Only few studies, however, have considered the differences between battery cages and alternative systems with regard to infectious diseases. The existing gaps in the current knowledge need to be closed by research and measures must be developed that will prevent the spread of viral, bacterial, and parasitic infections in alternative poultry housing systems.With regard to virus infections, avian influenza requires particular attention. Since wild birds, particularly anseriformes, represent a reservoir for avian influenza viruses, free-ranging poultry is much more at risk of infection than birds in closed hen-houses. Appropriate measures must prevent direct contact with wild birds and transmission via contaminated water, feed, or equipment. Several bacterial infections of poultry represent zoonoses. Salmonella and Campylobacter are considered as particularly important. To avoid a potential increase in the risk of infection for consumers due to poultry keeping systems that might favour infections with bacterial zoonotic agents, there is a special need for research in this area. With regard to parasitic infections, coccidioses may cause problems in alternative poultry housing systems, and lead to considerable economic consequences. The epidemiological situation concerning infections with Histomonas meleagridis needs to be analysed. Since all compounds that had been used for prophylactic or therapeutic purposes in the past have been banned, there is a need to develop new drugs which are safe for animals and humans.  相似文献   
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The aim of this study was to investigate in 20 healthy pigs the practicability of the oesophagogastroduodenoscopic examination technique in regard to equipment, method of examination, indications and its suitability as a diagnostical tool for the assessment of the oesophagus, stomach and upper duodenum in one procedure. Preparation of the patient for endoscopy, the procedure of the endoscopic examination as well as the topographical findings of the upper intestinal tract including the duodenum until the flexura duodenojejunalis are described. Flexible oesophagogastroduodenoscopy is a suitable method for the observation and natural visualisation of mucosal surfaces and for the digital documentation of peristaltic movements. The procedure is easy to perform in anaesthetized animals, is in most cases completed within 15 min, and can be repeated in the same animal. Indications of this interesting diagnostic imaging technique are discussed.  相似文献   
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Thirteen infectious laryngotracheitis virus (ILTV)-specific monoclonal antibodies (MAbs) were isolated after immunization of mice with purified infectious laryngotracheitis virions. On the basis of their reactions in western blot analyses of ILTV-infected cells, the MAbs were assigned to five different virus proteins or protein groups. Two of the viral target proteins could be identified after transient expression of cloned ILTV genes in eucaryotic cells. The MAbs of group II detected a 60-kD protein that was shown to be the ILTV homologue of herpes simplex virus type 1 (HSV-1) glycoprotein (g)C. The MAbs of group I reacted with the positional homologue of HSV-1 gJ, which is encoded by the open reading frame (ORF) 5 gene within the unique short genome region of ILTV. The ORF 5 gene product of ILTV was previously described as a 60-kD glycoprotein (gp60), whereas multiple protein bands with apparent molecular masses of 85, 115, 160, and 200 kD were identified in the present study. Immunoelectron microscopy revealed that both gC and gJ of ILTV are localized in the envelope of virus particles, whereas the 15-kD protein detected by the MAbs of group III presumably represents a tegument component. Immunofluorescence analyses of infected cells demonstrated that the epitopes of the gC- and gJ-specific MAbs are conserved in all tested ILTV isolates originating from different parts of the world and that these MAbs are also suitable for in situ antigen detection in tissues of ILTV-infected chickens. The remaining ILTV-specific MAbs recognized viral proteins of 22 kD (group IV) and 38 kD (group V) that were not further characterized up to now.  相似文献   
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