NEUROLOGICAL DISRUPTION PRODUCED IN HENS BY TWO ORGANOPHOSPHATE ESTERS.

A histological and enzymatic examination was made of the neurological disruption produced in hens by two organophosphate esters. Intraperitoneal administration of DEF (tributyl phosphorotrithiolate) and Merphos (tributyl phosphorotrithioite) produced central and perpheral nervous system lesions accompanied by clinical signs of ataxia similar to those seen following administration of tri-o-cresyl phosphate. Histological examination (utilizing the Marchi stain) showed the occurence of spinal cord disruption before the onset of clinical ataxia. Oral administration of DEF and Merphos did not induce signs of peripheral weakness. However, severe lesions in the spinal cord and sciatic nerve were prominent. A discussion of the occurrence of central and peripheral nerve disruption either in the presence or absence of clinical ataxia is presented. Enzymatic examination of the effect of DEF on spinal cord and brain esterases at various intervals following administration showed a pattern of esterase inhibition similar to that found after tri-o-cresyl phosphate, dyflos and other organophosphates. Some prolonged inhibition is believed due to the extent of initial involvement rather than to selective prolonged inhibition.