Light and electron microscopic lesions in peripheral nerves of broiler chickens due to roxarsone and lasalocid toxicoses.

ABSTRACT

This paper characterizes the light microscopic and ultrastructural lesions in peripheral nerves caused by feeding lasalocid and roxarsone to broiler chickens. The birds were given three different doses of each compound the standard industrial dose, 150% of the standard dose, and 200% of the standard dose. It was necessary to deprive the birds of water for 4 hours daily and heat-stress them in order to reproduce the lesion. Each compound caused mild microscopic lesions of swollen axons, digestion chambers, shrunken axons, or vacuoles where axons were missing. Ultrastructural changes included formation of myelin ellipsoids, vacuoles within or beneath the myelin sheath, and unraveling of myelin. These lesions were most frequently found in the birds receiving lasalocid.