Kelawala D N, Patil D B, Parikh P V, Sheth M J, Joshi C G, Reddy B
Ph.D. Scholar in Veterinary Surgery and Radiology, Department of Veterinary Surgery and Radiology, College of Veterinary Science and Animal Husbandry, Anand Agricultural University, Anand, Gujarat-388001, India.
Department of Veterinary Surgery and Radiology, College of Veterinary Science and Animal Husbandry, Anand Agricultural University, Anand, Gujarat-388001, India.
Iran J Vet Res. 2017 Spring;18(2):119-123.
During a 2-year period, 31 cases of a hereditary retinal degeneration in dogs bred in India were found mainly suspected for progressive retinal atrophy (PRA) with typical history of initial nyctalopia followed by hemeralopia. Out of 31 PRA suspected dogs, 8 dogs (26%) were from the age group of 1-5 years, 15 (48%) 6-10 years and the rest (26%) 11-15 years. The most predominant breed was Spitz (18 dogs, 58%). Detailed ophthalmologic examinations included Schirmer's tear test, fluorescein stain, applanation tonometry, slit lamp biomicroscopy and ocular ultrasound in appropriate cases. Ophthalmoscopic and fundoscopic changes included hyperreflectivity and discoloration of the tapetal area, marked attenuation of retinal vessels, depigmentation in non-tapetal area and optic disc atrophy with scalloped borders. Electroretinograms (ERG) recorded in 13 PRA-affected cases revealed non-recordable extinguished (flatline) ERG responses. A reduction mainly of a- and b-wave amplitudes in the ERG indicated a generalized photoreceptor disease.
在两年时间里，在印度繁育的犬类中发现了31例遗传性视网膜变性病例，主要怀疑为进行性视网膜萎缩（PRA），具有典型的初始夜盲病史，随后出现昼盲。在31只疑似患有PRA的犬中，8只（26%）年龄在1至5岁之间，15只（48%）在6至10岁之间，其余（26%）在11至15岁之间。最主要的品种是斯皮茨犬（18只，58%）。详细的眼科检查包括在适当情况下进行的泪液分泌试验、荧光素染色、压平眼压测量、裂隙灯生物显微镜检查和眼部超声检查。检眼镜和眼底镜检查的变化包括反光层区域的高反射性和变色、视网膜血管明显变细、非反光层区域色素脱失以及边界呈扇形的视盘萎缩。在13例受PRA影响的病例中记录的视网膜电图（ERG）显示为不可记录的熄灭（平线）ERG反应。ERG中主要是a波和b波振幅降低，表明存在广泛性光感受器疾病。
