PRA-RCD1 Sloughi Type (Progressive retinal atrophy)
PRA-RCD1 Sloughi Type belongs in progressive retinal atrohy group of disordes. Progressive retinal atrophy (PRA) comprises autosomal recessively inherited diseases that lead to degeneration of retinal photoreceptor cells in dogs and other pets. In general, these diseases are characterized by disturbance of dark vision, visual field defects, and abnormalities in the electroretinogram, which can progress to blindness. The age of onset and rate of retinal degeneration varies between the different forms of the conditions. Some forms of PRA are common to multiple dog breeds, while others are recognized in just a single breed.
Rod-cone dysplasias are group of recessively inherited diseases with early onset where photoreceptors are disturbed in their normal development and never manage to develop properly. The progression of rod-cone dystrophy is caused by sequential degeneration of rod and cone photoreceptors.
Retinal development is normal in PRA-RCD1 affected Sloughis until about two weeks of age, at which point photoreceptor development is arrested. Rod degeneration then occurs gradually from 1 to 5 months of age, followed by cone loss within 1 to 2 years. Early symptoms of PRA-RCD1 include night blindness and loss of peripheral vision due to progressive rod photoreceptors degeneration. This phase is followed by cone death and concomitant loss of central day vision. There is currently no cure for the
PRA-RCD1 disease type.
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