Encephalomalacia with Enterococcus durans Infection in the Brain Stem and Cerebral Hemisphere in Chicks in Japan

Abstract

Fourteen chicks, 7-12 days old, that died or had neurological signs (depression, paralysis, torticollis, incoordination, and rolling) were investigated pathologically and microbiologically. Variably sized foci of malacia were present within the parenchyma of the brain stem (cerebral peduncle, optic lobe, and medulla oblongata) and the cerebral hemisphere. Capillary thrombosis with congestion and hemorrhage was frequently observed within the malacia lesions. Gram-positive cocci were recognized in the blood capillary of malacia lesions. Bacteriologically, Enterococcus durans was isolated from the brain, liver, kidney, lung, and spleen. Detection of gram-positive cocci within the blood vessels in the malacia lesions observed in these cases may more strongly suggest the pathogenic role of E. durans on the malacia lesions in the brain stem and cerebral hemisphere.