番鸭白点病发病机理的研究

用番鸭白点病病毒人工感染雏番鸭后第 1、3、5、7、1 0、1 4d分别采集免疫器官和消化器官进行病理剖检和病理组织学观察 ,并测定血浆中的丙二醛 (MDA)和一氧化氮 (NO)含量 ,以研究白点病的发病机理。结果 ,感染后第 1d ,胸腺、脾、腔上囊开始出现肿大、出血和充血的现象 ,第3～ 7d病变较严重。胸腺以淋巴细胞坏死和减少为主要病变 ;脾除了淋巴细胞坏死和减少外 ,还有单核细胞浸润和髓窦红细胞淤积现象 ;腔上囊以淋巴细胞坏死和单核细胞浸润为主要病变。染毒后第 3d ,食管、腺胃、肝、胰、小肠等开始出现少量炎性细胞和红细胞浸润 ,第 5d时各消化器官都有不同程度的变性和坏死 ,随着病程的发展 ,炎性细胞和红细胞逐渐增多。第 1 0d时病变开始减轻 ,炎性细胞和红细胞浸润减少。血浆MDA含量在感染后第 3d开始升高 ,到第 5d时感染组显著高于对照组。血浆NO水平在感染后第 1d就开始升高 ,至第 7d达顶峰。试验结果提示 ,MDA和NO参与了白点病的病理过程

Pathogenesis studies of white spot disease in young Muscovy ducks

The immune and digestive organs were observed pathologically and plasma MDA and NO contents were measured in the young Muscovy ducks infected with white spot (disease) virus on day 1,3,5,7,10 and 14 post-infection, respectively. The results were as follows. The thymus, spleen and Fabrician pouch of the infected ducks showed the characters of swelling, hyperemia and bleeding on day 1 post-infection, and the pathological changes were further aggravated from day 3 to day 7 post-infection. The lymphocytes (necrosed) and their number decreased in the thymus, spleen and bursa of Fabircius. The blood red cells and inflammatory cells infiltrated into the gullet, stomach, liver, pancreas and small intestine on day 3 post-(infection). All digestive organs revealed degeneration and necrosis obviously on day 7 post-infection. With the development of the disease, the red cells and inflammatory cells became more and more until on day 10 post-infection, and then the pathological changes disappeared gradually. The concentration of plasma MDA increased on day 3 post-infection. The contents of plasma NO increased on day 1, and reached peak on day 7 post-infection. The results implied that free radicals may play an important role in the pathological process of white spot disease in young Muscovy ducks.