Comparative Morphological Studies on Lyssa in Carnivores and Camels with Special Reference to Its Surgical Resection

The lyssa is a morphologically supporting structure situated along the median plan on the ventral surface of the apex of the tongue in some animals. The present study aimed to describe the morphological differences of the lyssa in carnivores (dog and cat) and camel using conformist macroscopic and microscopic methods as well as evaluation of its surgical resection in the dog and cat. The lyssa is a rod-shaped in dog, strip like structure in cat and ridge-like structure in camel. It showed straight course in dog and helical appearance in cat. In the studied species, the lyssa was formed from adipose tissue intermingled with irregular connective tissue. However, dense striated muscles fibers were seen in the caudal half of the lyssa in dog. Besides, few bundles of longitudinally running muscle fibers were observed in cat and camel. In dog, the lyssa was defined by a coarse sheath of connective tissue, this capsule was ill-defined in cat and absent in camel. In cat, a pyramidal extension of the adipose tissue of the lyssa was attached to intrinsic striated muscle of the tongue. Full function of the tongue could be achieved after surgical resection of lyssa in dogs and cats