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某家蚕养殖场突发疾病，发病迅速。当蚕感染后，小蚕一般经3～4d，大蚕4～6d发病死亡。患病蚕由于发育阶段不同，外表症状也有差异，多数表现为体色乳白，体躯肿胀，狂躁爬行，体壁易戤。大蚕常爬行到蚕匾边缘堕地，流出乳白色脓汁而死。病蚕初死时，由于脓汁泄尽，体壁贴于消化管上，外观呈暗绿色。不久，尸体腐败变黑。该病的病原最可能是A、真菌 B、核型多角体病毒 C、微孢子虫 D、细菌 E、质型多角体病毒 该病最常用的临诊诊断方法是A、病原分离 B、显微镜检查 C、PCR检测 D、电泳检测 E、肉眼观察法 以下哪一种防治方法不可行A、合理布局，切断垂直传播 B、增施有机肥，提高桑叶质量 C、严格提青分批，防止蚕座传染 D、选用抗病力较强的品种 E、消灭桑园害虫，防止交叉传染
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