中国农业科学Issue(24)：5217-5227,11.DOI:10.3864/j.issn.0578-1752.2013.24.016
鸭出血性大肠杆菌O46分离株实验病理模型的建立
Establishment of an Experimental Pathological Model by Using EHEC O46 Isolate in Duck
摘要
Abstract
[Objective]This experiment was conducted to build an experimental pathological model of EHEC O46 isolate and observe its dynamic distribution, and the dynamic changes of histopathology and ultra-structural pathology in experimentally infected ducklings.[Method]The 10-day-old ducklings were infected with 0.5 mL of O46 isolate(2×108CFU·mL-1)through oral, intramuscular and subcutaneous injection separately. Tissue samples of heart, liver, spleen, lung, kidney, cerebra, esophagus, thymus, duodenum, jejunum, cecum, rectum, bursa of fabricius, pancreas and trachea were taken from the infected ducklings after being infected for 2, 4, 6, 12, and 24 h, and ever since for every 12 hours to make tissue biopsies and ultrathin sections, which were then stained with haematoxylin and eosin (H.E), as well as uranyl acetate, lead citrate and immunohistochemistry to observe the changes of histopathology, ultra-structural pathology and the bacterial antigen localization in experimentally infected ducklings. [Result]Same clinical symptoms as with naturally infected cases were duplicated in experimental pathological model. Bacterial antigens were detected in different tissues except trachea. The target tissues were hearts, lungs, spleens, kidneys and intestinal tracts where bacterial antigen located in cytoplasm and the positive signals were found in heart firstly. Necropsy, histopathological changes and ultra-structural pathological changes showed that main pathological damages of EHEC O46 isolate in ducklings were as follows:serous generalized fibrinous inflammation could be seen;hyperemia, hemorrhage and inflammatory cell infiltration were presented in heart, liver, spleen, lung, kidney, bursa of fabricius, intestinum tenue, pancreas and cerebrum;histopathological changes of necrosis and apoptosis were displayed in parenchyma cell such as renal tubular epithelial cell, hepatocyte, cardiomyocyte and enterocyte;reduction of lymphocytes could be seen in bursa of fabricius. E.coli was observed in heart, lung, spleen, liver, and intestinum tenue by SEM. The target tissue cells where isolate located were lymphocytes, macrophages, enterocytes and cardiac fibroblasts.[Conclusion] EHEC O46 isolate in duck showed high pathogenicity in ducklings. Pathologcial changes such as hemorrhagic enteritis and hemolytic uremic syndrome caused by EHEC were duplicated in experimental pathological model. It was concluded that O46 isolate was the pantropic bacteria injuring most tissues and cells in ducklings, and the principal target organs were heart, lung, spleen, kidney and intestine.关键词
O46分离株/EHEC/实验病理模型/病理变化Key words
O46 isolate/EHEC/experimental pathological model/pathological change引用本文复制引用
于学辉,李键,程安春,黄志宏,罗薇,冉丹丹..鸭出血性大肠杆菌O46分离株实验病理模型的建立[J].中国农业科学,2013,(24):5217-5227,11.基金项目
国家农业（水禽）产业技术体系岗位科学家专项（CARS-43-8）、国家“863”项目（2012YAA101304）、中央高校基本科研业务费科研平台建设项目（11NPT03）、四川省创新团队（12TD005/13TD015）和国家“十二五”国家科技支撑计划 （）
