Eosinophilic Meningitis in Two Cows

Abstract

A neurological disorder was noted in 5 cows on a farm. Histopathological examination in 2 of these 5 animals revealed an infiltration of eosinophils with some macrophages in the meninges and around arterioles of the cerebral cortex. The endothelial cells of the reactive blood vessels were swollen. From these observations, the brain lesions were diagnosed as "eosinophilic meningitis". In one case, pulmonary arterioles were also infiltrated with eosinophils and macrophages in a granulomatous tissue. No bacteria, fungi, protozoa, or parasitic worms were detected in the present cases.