Assessment of a Novel Pigmentary Chorioretinopathy in the Chinese Crested Dog

• One hundred and twenty seven privately owned Chinese Crested Dogs (CCDs) were screened for Presumed Inherited Eye Disease (PIED). Thirty five cases of a recently discovered presumed inherited pigmentary chorioretinopathy were diagnosed and used for preliminary characterization of the disease using clinical and laboratory methods. Electroretinography (ERG) in ten affected and in nine normal CCDs was performed and morphology was obtained in one normal and in three affected 6-8 year-old dogs. A bilateral and mainly symmetrical retinal dystrophy with circumscribed pigmented lesions was observed, the earliest changes observed in 3-year-old dogs. The lesions showed a lighter center (pimple-like) and areas between lesions were often grayish and hypo reflective. Changes were mainly prevalent in the peripheral fundus initially. In more advanced cases the circumscribed pigmented changes were also observed centrally. In some cases there was diffuse hyper reflectivity in the area of the pigmented changes and slight vascular attenuation, indicating more generalized retinal degeneration. ERGs were not diagnostic in the early disease stage. Morphology showed changes at the level of the Retinal Pigment Epithelium (RPE), with focal areas of increased layering of RPE cells and detachment of RPE cells with subretinal migration. There were also areas of severe RPE and photoreceptor degeneration or atrophy with outer nuclear layer remnants in direct contact with the choroidal tissue. The circumscribed pigmented lesions observed ophthalmoscopically corresponded to these areas of geographic atrophy. The disease appears to be slowly progressive and in some cases, but not all, the disorder results in visual impairment or blindness.

Subject headings

LANTBRUKSVETENSKAPER  -- Bioteknologi med applikationer på växter och djur -- Genetik och förädling inom lantbruksvetenskap (hsv//swe)

AGRICULTURAL SCIENCES  -- Agricultural Biotechnology -- Genetics and Breeding in Agricultural Sciences (hsv//eng)

Publication and Content Type

ref (subject category)

art (subject category)