Lead Poisoning in Cattle Held in a Military Training area

Background: Lead poisoning is one of the major toxic diseases of cattle. Contamination occurs with ingestion of products containing lead, especially batteries, or through contaminated pastures and water sources. Clinical signs are neurological and necropsy findings and histopathological changes may vary depending on the clinical presentation. Although the diseaseis widely reported in the literature, there are rare descriptions of intoxication in cattle raised in military training areas. This work describes the epidemiological, clinical and anatomopathological features of an outbreak of lead poisoning in cattle kept in a military artillery training camp.Case: Fifteen cattle out of a herd of sixty 4-6 year-old, mixed breed castrated males were affected. The cattle were held in a 100 ha of native pasture used for military artillery training. After three weeks in this area, the affected cattle had predominantly neurological clinical manifestations, characterized by somnolence, ambulatory incoordination, muscle tremors,bruxism, aimless walking, blindness and decubitus. The clinical course was 24-72 h. Eight of the 15 affected cattle died and two were necropsied. Necropsy finds were non-specific and the histological lesions of both necropsied cattle were restricted to the brain and kidneys. Laminar neuronal necrosis, neuropil vacuolization (spongiosis) and vascular endothelial hypertrophy were observed in the telencephalic cortex. Additionally there was astrocytic degeneration and neuronophagia.There was degeneration and necrosis of renal tubular epithelium and in one bovine there were intranuclear inclusion bodies in the renal epithelial cells; these inclusion bodies were highlighted using both modified Ziehl-Neelsen and periodic acid Schiff (PAS) stains. The levels of lead found in the kidneys and livers of the two necropsied cattle were respectively51.7 μg/g and 41.00 μg/g for one of the necropsied cattle; and 431μg/g and 39.0 μg/g for the other. After the diagnosis of intoxication, cattle were removed from the area and the remaining seven affected bovines recovered.Discussion: The diagnosis of lead poisoning in cattle in the current study was based on epidemiological, clinical, anatomopathological data and in the determination of lead levels in the kidney and liver. The association of these data provides an invaluable aid in confirming a presumptive diagnosis of lead poisoning. Pasturing on military artillery training fieldsis a rarely described form source