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近年来，上海郊区饲养中国对虾（Ｐｅｎａｃｕｓｃｈｉｎｅｓｉｓｏｓｂｅｃｋ）的虾塘发生大面积的流行病。经对病虾的鳃、肝、胰腺或中肠组织进行超薄切片处理及电镜观察，发现在这些组织的细胞核内存在大量有囊膜包裹的杆状病毒，有时一个囊膜还可同时包裹两个病毒的核衣壳。经有机溶剂处理、差速离心及密度梯度离心，可以获得部分提纯的病毒和病毒核衣壳制剂。超薄切片中，病毒粒子大小约为４４０－５００×１７０－１８０ｎｍ，核衣壳大小约３３０－４２０×１１０－１４０ｎｍ，提纯的核衣壳粒子大小约为３５０－４００×７０－８５ｎｍ。无论在超薄切片或在分离提纯的制剂中，均未观察到有包涵体存在。将部分提纯的病毒制剂人工感染健虾，结果发现肌注的对虾死亡率达９０％以上，饲毒的死亡率各在５０％左右。这些结果证明，所发现的杆状病毒可能就是引起这次上海郊区对虾大规模死亡的主要原因。
In recent years, a large epidemic of shrimp ponds has been found in Penacuschinesisosbeck, a suburb of Shanghai. The gill, liver, pancreas or midgut tissues of diseased shrimp were ultrasonically sliced and observed by electron microscopy. It was found that there were a large number of enveloped baculoviruses in the nuclei of these tissues, and sometimes one capsule could simultaneously wrap two A virus nucleocapsid. After organic solvent treatment, differential centrifugation and density gradient centrifugation, partially purified virus and virus nucleocapsid preparations can be obtained. In the ultrathin sections, the virus particle size is about 440-500 × 170-180nm, the size of the nucleocapsid is about 330-420 × 110-140nm, and the size of the purified nucleocapsid particles is about 350-400 × 70-85nm. Inclusion bodies were not observed either in ultrathin sections or in isolated and purified preparations. The partially purified virus preparations were artificially infected with shrimp, and found that the mortality of intramuscular shrimp reached more than 90%, and the mortality rate of feeding poison was about 50%. These results demonstrate that the baculovirus found may be the main cause of the large-scale death of shrimp in the suburbs of Shanghai.