Caracterização clínica, epidemiológica e anatomopatológica da neuropatia periférica em bovinos no Mato Grosso do Sul

Abstract

Cases of disease in cattle have been followed in the diagnostic routine with a clinical picture characterized by atypical and constant flexion of the metatarsophalangeal joints, especially when they are stimulated to walk or run and stop abruptly. This study aims to perform the epidemiological, clinical and pathological characterization of peripheral neuropathy in cattle in Mato Grosso do Sul. Cattle remain alert and do not show other clinical changes. Some animals evolve to decubitus and death and others recover spontaneously. The cases occur in rainy periods and high temperatures, which comprise the months of December to March in the southern hemisphere. Macroscopically, there was edema around the nerves and discrete hemorrhages. Microscopic lesions are characterized by peripheral neuropathy. There is demyelination of the peripheral nerves of the pelvic limbs and, to a lesser extent, of the thoracic limbs, Wallerian degeneration was observed, characterized by marked swelling of the myelin sheath and formation of digestion chambers. The most affected nerves were the sciatic, tibial, and fibular nerves. The measurement of copper and selenium concentrations in the liver were below physiological levels, but it was not possible to associate these results with the pathology of the disease. Seasonal disease with similar clinical signs has been reported in horses from Nordic countries, and has been related to toxic etiology of dietary origin. No similar reports were found in cattle and this highlights the need for further studies to elucidate the etiology of the disease.