Sensory neuropathy produced in the cat with thallous acetate

A method of poisoning cats with thallium is described. The chief functional disturbances in the nervous system are hypotonia and ataxia. The pathological changes are confined to the central and peripheral axons of primary sensory neurones and are of the 'dying back' type. No motor nerve fibre degeneration was found in this species. While extensive degeneration of sensory nerves was found, those in muscle were apparently unaffected. The significance of this anomalous finding is discussed in relation to the mechanism of the 'dying back' process.