Nerve fibers, also called axons, are long thread-like projections of nerve cells (neurons). The neuron’s axons normally send impulse transmissions to other nerve cells, muscles and gland cells. In NAD, the progressive degeneration of nerve cells causes spheroids to form on the nerve endings. The nerve cells are no longer able to normally transmit to each other. Abnormal nerve conduction causes the loss of coordination.
Canine newborns with NAD can be born with respiratory failure, scoliosis, and joint contractures (arthrogryposis). Additionally, they can be born with cerebellar hypoplasia (not completely mature); the cerebellum is the part of the brain that controls fine motor skills and coordination. There are dogs that do not show symptoms until they are into their adult life.
Breeds that are predisposed to NAD are the Papillons, Chihuahuas, Rottweilers, Border Collies, Dachshunds and the Jack Russell Terriers.
Neuroaxonal dystrophy (NAD) in dogs is usually an autosomal genetic disease, which causes progressive degeneration of the nerve cells of the peripheral and/or central nervous system. The progressive damage to the nerve cells leads to spheroids to develop and build up on the nerve fibers.