Some epidemiological aspects and pathological alterations particularly blood filled cysts in liver tissue (peliosis hepatis) in association with chronic pulmonary tuberculosis in cross bred cows were evaluated. Animals were screened through single comparative cervical intradermal tuberculin (SCCIT) test. The results revealed 7.47% prevalence of bovine tuberculosis (BTB) in animals. The frequency analysis on certain epidemiological aspects revealed that the prevalence of disease was non-significantly different with age, sex and lactating status of animals. Necropsy revealed multiple tubercles of variable size throughout the lungs. Trachea and bronchial tree was extensively plugged with thick yellow ropy purulent exudates. Microscopically lungs exhibited characteristic cluster of small and large size miliary nodules with caseated center and lamellar arrangement of dystrophic mineralization surrounded by multinucleated giant cells, epithelioid macrophages, plasma cells, lymphocytes and fibrous proliferation. Lung tissues stained with Ziehl-Neelsen expressed masses of slender acid-fast bacilli in the necrotic centers of lesions. Moreover, in liver sections angiomatoid cysts (peliosis hepatis) lined with hepatocytes were extensively observed. The infectious agent (Mycobacterium bovis) was confirmed using PCR. It was concluded that histopathological observations such as peliosis hepatis are useful information for the differential diagnosis of acute verses chronic process of bovine tuberculosis.

Key words: Cattle, Pathology, Peliosis hepatis, Pulmonary tuberculosis