Pathological observations on clinical Anaplasma marginale infection in cattle.

Gross and histopathological changes were recorded in a pregnant cattle died of clinical anaplasmosis, a tick transmitted economically important disease caused by Anaplasma marginale. Grossly emaciated carcass along with pale visible mucous membranes and pale serosal surface, splenomegaly and hepatomegaly was observed. Microscopically, in lungs variable extend of interstitial pneumonia, emphysema along with infiltration of mononuclear cells was seen. Spleen showed extensive increase in red pulp area with massive proliferation of lymphocytes. In liver marked thickening of capsule with fatty changes along with retention of bile was seen. Gall bladder showed congestion, glandular hyperplasia and thickening wall. Myocardium showed degeneration and necrosis.