Maedi-visna (MV) is an important slow viral disease of sheep leading to a progressive lymphoproliferative disease. It affects multiple organs primarily the lungs, where it causes interstitial pneumonia (maedi). In this study, the lungs of 1,000 sheep carcasses were grossly inspected and those suspected to have maedi were studied at histopathological and molecular levels. A polymerase chain reaction (PCR) technique that amplified a 291-base pair DNA in the long terminal repeat (LTR) sequence of MV provirus was conducted on all the 50 suspected lungs together with 10 normal appearing lungs as controls. Amplicons of the expected size were detected in 11 (n=11/50) suspected sheep, and one of the 10 control sheep. Histopathologic study of the pulmonary lesions of all 11 (n=11/11) positive sheep showed MV lesions, including hyperplasia of the perivascular and peribronchiolar lymphoid cells, interstitial lymphoplasmacytic infiltration and smooth muscle hyperplasia and the histopathologic findings were correlated with PCR results. In contrast, the tissue sections of control animals were almost normal at histopathological level; however, PCR technique demonstrated that one of them was affected by maedi. This study showed that the LTR-PCR had high specificity and sensitivity in diagnosis of this viral infection. This study is the first to evaluate the prevalence of MV virus infection in sheep in Iran.

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Haemangiosarcoma is a malignant endothelial cell tumour with rapid growth and poor prognosis. In animals, haemangiosarcoma is frequently reported in dogs as a visceral tumour. The present study describes a gingival haemangiosarcoma in a 2-month-old, female native breed calf with a tumour likemass on the gingiva. The owner had noticed the mass 2 weeks after birth due to salivation, bleeding and halitosis. It had rapid growth and caused anorexia and weight loss in the animal. Histopathologic examination showed a lot of thin-walled, irregular blood vessels lined by a single and less commonly two layers of endothelial cells. The lining cells were with spindle or ovoid shape with vesicular to hyperchromatic nuclei and prominent nucleoli. There were remarkable thrombi in some vessels. The reported lesions were diagnosed as haemangiosarcoma based on histopathologic characteristics such as irregular vascular canals and polymorphism of neoplastic endothelial cells. Haemangiosarcoma is rare in the oral cavity of cattle.

Pneumoconiosis is an occupational lung disease which occurs by the accumulation of inhaled organic and inorganic particles in the pulmonary parenchyma. These particles interfere with the defense mechanisms of the lungs. This study was designed to describe the gross and histopathological features of pneumoconiosis in the lungs and its relation with occurrence of pneumonia in camels. 150 pneumonic and 100 healthy lungs were examined for pneumoconiosis in pathologic level. Macroscopic lesions of pneumoconiotic lungs were related to pneumonia and no remarkable features of pneumoconiosis were observed in the examined tissues. Pneumoconiosis was diagnosed in 43 out of 150 lungs with pneumonic lesions. Grossly healthy lungs did not show pneumoconiosis. Out of 43 pneumoconiotic lungs, 93% (n=40/43) were associated with interstitial pneumonia. Also, pneumoconiosis occurred in 2.32% (n=1/43) and 4.65% (n=2/43) of lungs with suppurative bronchopneumonia and bronchointerstitial pneumonia, respectively. Histopathologic findings related to pneumoconiosis were characterized by varying degrees of diffuse to nodular fibrosis as well as mild to heavy accumulations of mixed carbon and silicon dusts. Interlobular and interalveolar septa of alveoli were thickened by fibrosis and infiltration of mononuclear inflammatory cells. Crystalline silicon particles were in different shapes including filamentous, oblong and polygonal. Anthraco-silicosis particles were observed inside and outside of macrophages more adjacent to the vessels and bronchioles as well as lymphocytes infiltration. The color of particle aggregations was different from scant gray to brown or dense black, depending on the amount of silicon or carbon dust deposition. In the lungs, areas with prominent deposition of crystalline silica rather than carbon were gray to light brown and focal interstitial fibrosis was occurred. The present study suggests a positive causal relationship between pneumoconiosis and pneumonia. It seems these particles predispose animals to pulmonary diseases especially various type of pneumonia. Keywords: Pneumoconiosis, Pathology, Silicosis, Anthracosis, Camel Tek Hörgüçlü Develerde (Camelus dromedarius) Anrako-silikozisin Akciğerlerdeki Patolojik Bulguları ve Pömoni Oluşumundaki Rolü ÖzetPnömokoniozis pulmoner parankimde solunan organik ve inorganik partiküllerin birikmesi ile oluşan bir akciğer hastalığıdır. Bu partiküller akciğerlerin savunma mekanizmalarını bozarlar. Bu çalışma develerde pnömokoniozisin makroskopik ve histopatolojik özelliklerini tanımlamak ve pnömoni oluşumu ile ilişkisini ortaya koymak maksadıyla yapılmıştır. Çalışmada 150 pnömonili ve 100 sağlıklı akciğer pnömokoniozis yönünden incelendi. Pnömokoniotik akciğerlerdeki makroskopik lezyonlar pnömoni ile ilişkilendirildi ve incelenen dokularda pnömokoniozisin belirgin hiçbir özelliği gözlemlenmedi. Pnömoni lezyonlu 150 akciğerden 43'ünde pnömokoniozis tespit edildi. Makroskopik olarak sağlıklı akciğerlerde pnömokoniozis gözlemlenmedi. 43 adet pnömokonitik akciğerin %93'ü (n=40/...