Catap E S, Lavilla-Pitogo C R, Maeno Y, Traviña R D
Fish Health Section, SEAFDEC Aquaculture Department, Tigbauan, 5021 Iloilo, Philippines.
Dis Aquat Organ. 2003 Dec 3;57(1-2):11-7. doi: 10.3354/dao057011.
Hepatopancreatic parvovirus (HPV) was detected in samples of Penaeus monodon post-larvae (PL-13, PL-18, PL-19, PL-26) from 2 hatcheries in 2 provinces (Samar and Iloilo) in the Philippines. The percentage of infection was 20 to 100% in postlarvae obtained from the hatchery in Samar in August 2001. Postlarvae from the hatchery in Iloilo, sampled in October and November 2001, had 70 to 99% HPV infection. Wet mounts of squashed hepatopancreatic tissue stained with malachite green (wet-mount technique) and histopathology revealed the presence of large, usually single, basophilic intranuclear inclusion bodies in the distal tubules, which led to displacement of the nucleoli. Light microscopy showed ovoid to spherical inclusion bodies, 5 to 11 mmicrom in diameter. Transmission electron microscopy revealed that the inclusion bodies were composed of electron-dense granular material and virions. The virions appeared roughly spherical and averaged 18 to 22 nm in diameter. An experiment was undertaken to induce HPV infection by feeding P. monodon postlarvae with virus-infected postlarvae. P. monodon postlarvae (PL-16), initially determined as free from HPV, were found HPV-positive 24 h after being fed with infected material. The percentage of infection ranged from 30% at Day 1 post-infection (p.i.) to 100% at Day 7 p.i. determined by the wet-mount technique and by histopathology. This is the first report of a successful horizontal transmission of HPV in P. monodon postlarvae.
在菲律宾两个省份（萨马尔省和伊洛伊洛省）的2个孵化场的斑节对虾后期幼体（PL - 13、PL - 18、PL - 19、PL - 26）样本中检测到肝胰腺细小病毒（HPV）。2001年8月从萨马尔省孵化场获得的后期幼体感染率为20%至100%。2001年10月和11月从伊洛伊洛省孵化场采集的后期幼体HPV感染率为70%至99%。用孔雀石绿染色的肝胰腺组织压片湿片（湿片技术）和组织病理学检查显示，远端小管中存在大的、通常为单个的嗜碱性核内包涵体，导致核仁移位。光学显微镜显示卵形至球形的包涵体，直径为5至11微米。透射电子显微镜显示包涵体由电子致密颗粒物质和病毒粒子组成。病毒粒子呈大致球形，平均直径为18至22纳米。进行了一项实验，通过用感染病毒的后期幼体喂养斑节对虾后期幼体来诱导HPV感染。最初确定未感染HPV的斑节对虾后期幼体（PL - 16）在喂食感染材料24小时后被检测为HPV阳性。通过湿片技术和组织病理学检查确定，感染率在感染后第1天为30%，在感染后第7天为100%。这是关于HPV在斑节对虾后期幼体中成功水平传播的首次报道。
