The present study describes the multicentric lymphosarcoma associated with lymphoid interstitial pneumonia in indigenous breeds of sheep and goats in Pakistan. Serum samples from sheep (n=93) and goats (n=129) were screened for ovine lentivirus using agar gel immunodiffusion test. Overall, 7.52 and 3.87% seroprevalence was recorded in sheep and goat, respectively. During necropsy of sheep (n=3) and goats (n=4), gross lesions including dark color liver with multifocal whitish areas, unilaterally lungs consolidation with granular appearance of cut surface were observed. Mediastinal lymph nodes were swollen and arranged in chain like fashion. Histopathologically, liver parenchyma exhibited extensive proliferation of neoplastic cells of lymphocytic series. Metastatic cells in the form of follicular pattern in the lungs, spleen and mediastinal lymph nodes were also observed. Brain tissue exhibited degenerative changes in the neuron and perivascular cuffing. The PCR product size approximately 300 bp from lung tissue confirmed viral infection.

Key words: Lentiviurs, Lymphoid interstitial pneumonia, Multicentric lymphosarcoma, PCR, Small ruminants