Lead Poisoning in Cattle: Brain Lesions and Hematologic Changes

Abstract

SUMMARY Gross and microscopic examinations were made of 9 cattle, ranging in age from 3 months to 6 years, affected with naturally occurring lead poisoning of 1 to 32 days' duration. Lead poisoning was diagnosed initially on the basis of typical clinical signs and significant toxicologic observations. Gross brain lesions consisting of cerebrocortical softening, yellowish discoloration, and cavitation were seen only in cattle with prolonged clinical illness (affected for more than 9 days). Tips of most cerebral gyri were affected; lesions were most severe in the occipital lobes. In cattle with acute poisoning, microscopic lesions varied from diffuse capillary activation to scattered focal areas of status spongiosus and necrosis of the cerebral cortex. In cattle with subacute and chronic poisoning, the microscopic lesions were located at the gyral tips and ranged from different degrees of status spongiosus, astrocytic swelling, and nerve cell degeneration to severe cavitation and vascular proliferation.