Study on pathological changes caused by oestrus ovis in small ruminants of Jammu

Oestrosis caused by nasal bot, Oestrus ovis larvae is a common infestation of sheep and goats. However, being common, its pathogenic effects are often underestimated by both owners and veterinarians. The heads of sheep and goats collected from local abattoirs were examined to observe the gross and histopathological changes caused by larval instars of O. ovis. Gross symptoms observed were catarrhal discharge, purulent and bloody exudates and congestion. Histopathology of cerebral cortex from infected animals revealed neuronal degeneration with increased peri-neuronal space and softening of brain substance. Besides, engorgement of blood vessels and vacuolation of brain substance with increased number of glial cells and mild perivascular cuffing by mononuclear cells were also found. Nasal mucosa showed discontinuation of epithelial cells with mononuclear cell infiltration, oedema, fibrosis and engorgement of submucosal blood vessels.