Explorer Clinical features of the retinopathy , globe enlarged ( rge ) chick phenotype
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چکیده
The purpose of the study reported here was to characterize the clinical aspects of the autosomal recessive retinopathy, globe enlarged (rge) phenotype in chicks (Gallus gallus). Rge/rge, rge/+ and +/+ chicks were studied from hatch to 336 days of age by general clinical examination, post-mortem examination, vision testing with an optokinetic device, ophthalmoscopy, biomicroscopy, tonometry, central corneal pachymetry, a-mode ultrasonography, infrared photoretinoscopy and photokeratometry. Additionally, preliminary electroretinographic and histopathologic investigations were performed. There is a variable degree of vision loss in rge/ rge chicks at 1 day of age with further chicks losing vision over the next few weeks until all chicks become functionally blind by 30 days of age (although some optokinetic responses remain in some of the rge/rge chicks). Over the first few weeks of life rge/rge chicks develop thicker corneas with a larger radius, hyperopia, shallower anterior chambers and enlarged globes both radially and axially, compared to controls. A preliminary ERG study showed that 1 day old rge/rge chicks have an elevated response threshold, a lower amplitude a-wave with a markedly shallow leading slope, a lack of both oscillatory responses and c-waves and, at brighter flashes, an increased b-wave amplitude. Light microscopy revealed no gross retinal abnormalities in young chicks to account for the blindness. A thinning of all retinal layers developed in parallel with globe enlargement. The rge defect is a unique progressive retinal dystrophy that results in a severe visual deficit, abnormal electroretinographic waveforms, and secondary globe enlargement. 2003 Elsevier Ltd. All rights reserved.
منابع مشابه
Detailed histopathologic characterization of the retinopathy, globe enlarged (rge/rge) chick phenotype
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Electroretinographic features of the retinopathy, globe enlarged (rge) chick phenotype
PURPOSE The purpose of the study was to characterize the electroretinographic features of the autosomal recessive retinopathy, globe enlarged (rge) phenotype, in chickens (Gallus gallus). METHODS Dark-adapted, light-adapted intensity series and light-adapted 30 Hz flicker responses were recorded from rge and age matched normal control chicks from one to 270 days of age. Retinal sections from ...
متن کاملClinical features of the retinopathy, globe enlarged (rge) chick phenotype
The purpose of the study reported here was to characterize the clinical aspects of the autosomal recessive retinopathy, globe enlarged (rge) phenotype in chicks (Gallus gallus). Rge/rge, rge/+ and +/+ chicks were studied from hatch to 336 days of age by general clinical examination, post-mortem examination, vision testing with an optokinetic device, ophthalmoscopy, biomicroscopy, tonometry, cen...
متن کاملDetailed histopathologic characterization of the retinopathy, globe enlarged (rge) chick phenotype.
PURPOSE The purpose of this study was to characterize the morphological abnormalities in the retinas of chicks (Gallus gallus) suffering from the autosomal recessive disease, retinopathy, globe enlarged (rge/rge). METHODS rge/rge affected and age matched control retinas were examined from hatch up to 730 days of age. Thickness of retinal layers at six retinal regions was measured from plastic...
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In the cornea, the precise organisation of fibrillar collagen and associated proteoglycans comprising the stromal extracellular matrix plays a major role in governing tissue form and function. Recently, abnormal collagen alignment was noted in the misshapen corneas of mature chickens affected by the retinopathy, globe enlarged (rge) mutation. Here we further characterize corneal ultrastructural...
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