湖羊感染羊源性伪狂犬病病毒致病特征的研究OA北大核心CSTPCD

The aim of the present study was to investigate the features of pseudorabies virus(PRV)strain SH1 407 of sheep origin in Hu sheep.Seven healthy Hu sheep were randomly divided into test group(5 sheep)and control group(2 sheep).Five sheep in the test group were challenged with the SH1407 strain and tissue samples were collected for histopathological examination and immunohistochemical analysis.The infected sheep developed clinical signs at day 3 post infection and became severe illness including depression,anorexia,pruritus and high body temperature at day 4.Four sheep died within 3 days of the onset of signs and one survived.Gross lesions showed dural congestion,pulmonary congestion and consolidation.Microscopically,the major histopathological findings were neuron degeneration in brains and medullas,pathological nerve cell apoptosis,interstitial pneumonia and hemorrhage in spleens and kidneys.Immunohistochemical staining displayed that PRV existed widely in livers,lungs,brains,spleens and other organs.The viruses in livers mainly existed in Kupffer cells,type Ⅱ cells in lungs,macrophages and mononuclear cells in spleens,and neurons in brain tissues.The viral loads of internal organs were measured by real-time fluorescence quantitative PCR and extensively found in livers,spleens,lungs and brain tissues.Severe infection in brain tissues resulted in serious pathological changes of central nervous system.