Progressive retinal atrophy

Types of PRA
– PRAs can be categorized as dysplastic disease or degenerative disease.
– Night blindness is the first significant sign for most dogs with PRA.
– Generalized PRA causes atrophy of all neural retinal structures.
– Central progressive retinal atrophy (CPRA) is a different disease involving the retinal pigment epithelium (RPE).
– CPRA is also known as retinal pigment epithelial dystrophy (RPED).

Generalized PRA
– Commonly affected breeds include Akita, Miniature longhaired Dachshund, Papillon, Tibetan Spaniel, and Samoyed.
– Symptoms typically appear at different ages in each breed.
– Selective breeding has reduced the incidence of PRA in Akita.
– PRA3/RCD4 disease affects middle-aged Tibetan Terriers.
– Information on PRA3/RCD4 disease in Tibetan Terriers can be found at ttca-online.org.

Rod-cone dysplasia
– Rod-cone dysplasia is characterized by early onset severe vision loss.
– There are three types of rod-cone dysplasia: type 1, type 2, and type 3.
– Irish Setter and Sloughi are affected by rod-cone dysplasia type 1.
– Collie is affected by rod-cone dysplasia type 2.
– Cardigan Welsh Corgi is affected by rod-cone dysplasia type 3.

Rod dysplasia
– Norwegian Elkhound is characterized by dysplasia and degeneration of rod and cone cells.
– Night blindness typically appears by six months old and blindness by three to five years old.
– Rod dysplasia has been bred out of Norwegian Elkhounds.
– Norwegian Elkhound can also experience early retinal degeneration with night blindness by six weeks old and blindness by twelve to eighteen months old.

Photoreceptor dysplasia
– Photoreceptor dysplasia affects both rod and cone cells.
– Miniature Schnauzer experiences slowly progressive symptoms starting at two to five years old.
– Belgian Shepherd Dog is completely blind by eight weeks old.
– Alaskan Malamute temporarily loses vision in daylight at eight to ten weeks old.
– Glen of Imaal Terrier experiences gradual blindness starting around four years old.https://en.wikipedia.org/wiki/Progressive_retinal_atrophy