Studies On The Clinical And Molecular Pathology Of Sheep With Naturally And Experimentally Infected Pulmonary Adenomatosis

Sheep pulmonary adenomatosis (SPA) is a contagious tumour of sheep that is caused by the betaretrovirus. According to the OIE and the China ministry of agriculture classification, SPA is belong in the B-type and the third-type infectious disease, respectively.Based on the investigation of epidemiology, two natural cases with SPA from a region of Inner Mongolia were taken back to our laboratory,isolated until death .And the examination of clinical signs, blood samples, X-ray, necropsy, histopathology and ultrastructural pathology were carried out. At the same time, the seven newborn lambs(within 24 hours after birth) were inoculated intratracheally with (0.3ml/per lamb) cell-free filtration of pulmonary tumour tissue containing JSRV-NM strain from natural cases. And through the observation of eighteen-months long, the clinical pathology similarly as natural case of the four experimentally survived cases were examined. Additionaly, genomic DNA was prepared from the lung tumour tissues of two natural cases, fuor experimentally induced cases and six control sheep respectively, and in which detected the proviral DNA by PCR with a pair of primers designed by Primer Premier 5.0 software within the TM and LTR-U3 regions of the JSRV-NM strain sequences. Simultaneously, the dynamic changes of monocytes, lymphocytes and the subgrops of T lymphocytes and apoptosis of lymphocytes and monocytes of peripheral blood were examined both in natural cases and experimental cases by flow cytometry. The results showed that: (1) The two natural cases were both presented the classical clinical signs of SPA , the symptom named as"wheel barrow test", higher heat and breath rate than unaffected sheep, anaemia, and, cloudy-shaped firm lesions in the lungs by X-ray. (2) The lungs were considerably enlarged and its surface and cut surface showed numerous firm, differently-sized and pinkish-gray nodules.Some cases were found that chronic adhesive pleurisy which made it difficult to remove the lungs from the thorax.White frothy fluid may be seen in the bronchi and bronchioli at necropsy. (3) Histologically, the secretory epithelial cells in the pulmonary alveoli and epithelial cells of the bronchioli proliferated and formed papillar form that project into the alveoli or bronchioli. Large numbers of epithelial cells accumulated in the alveoli adjacent to the neoplastic lesions.(4)...