More prevalent in dogs than cats. A gradually progressing night blindness that ultimately affects vision in bright light. Owners may notice dilated pupils or brighter tapetal reflex at night.
Many affected dogs develop cataracts.
SARD dogs lose vision in 1-4 weeks, have increased thirst and urination, show increased hunger and may have slow or absent pupillary light reflexes. Affects both eyes symmetrically. Retinal degeneration can occur secondary to scarring from previous multifocal or diffuse retinal detachment or inflammation. Severe deficiency of Vitamin E or A may cause partial or complete retinal degeneration in dogs and cats. SARD may be idiopathic.