Ventricular encephalitis associated with leukaemic lymphosarcoma in a bovine calf

Abstract

A female Ayrshire calf aged three months was referred to the clinic with a history of generalized lymph node enlargement and failure to thrive. Physical examination revealed enlargement of all peripheral lymph nodes and haemonodes. A lymph node biopsy showed many immature lymphocytes in various phases of mitosis. Examination of a blood sample revealed normocytic normochromic anaemia, with many immature and abnormally shaped red blood cells. Although leukocyte count was within the normal range, lymphocytes were the majority (94%), with neutrophils constituting only 6%. Other leukocytes were absent. There were many immature and abnormal lymphocytes, similarly, there were immature and abnormal neutrophils. As a result, a clinical diagnosis of leukaemic lymphosarcoma was made. The calf died two weeks after admission. Postmortem examination revealed emaciation, enlargement of all lymph nodes, with involvement of the haemonodes, liver, kidneys and bone marrow. Microscopically, there were lymphocytic infiltrations in the liver, kidneys, spleen, lungs, abomasum, leptomeninges of the brain and in the subependymal areas of the ventricular system.