Epidemiology and clinical presentation of feline presumed hereditary or breed-related ocular diseases in France: retrospective study of 129 cats

Prevalence of feline ophthalmic disorders in South Korea: a retrospective study (2009-2021)

OBJECTIVES

This study aimed to determine the prevalence and clinical presentation of ocular diseases in cats in South Korea.

METHODS

Medical records of cats that were presented for ophthalmology services at Seoul National University Veterinary Medical Teaching Hospital between 2009 and 2021 were reviewed. Collected data included patient signalment, clinical signs, diagnosed ophthalmic disorders and affected eyes. Odds ratios were calculated when a variable was over-represented.

RESULTS

This study recorded a total of 358 eyes (180 cats). Domestic shorthair (DSH) was the most common breed (42.2%), followed by Persian (13.9%) and Scottish Fold (8.3%); 14 (35.6%) other breeds were recorded. The median age at the first presentation was 3 years (range 2 months to 17 years); the highest percentage of cats presented at <1 year (21.7%). The most affected ocular structure was the cornea (28.5%), followed by the lens (19.9%) and uvea (15.3%). The most frequently reported disorders were corneal ulceration (13.2%), uveitis (11.9%), incipient cataract (11.0%), keratitis (5.4%), secondary glaucoma (5.2%) and sequestrum (4.2%). The Exotic Shorthair breed was significantly over-represented with regard to entropion and periorbital fat prolapse (P <0.01). The DSH breed was significantly over-represented with regard to eyelid agenesis (P <0.01).

CONCLUSIONS AND RELEVANCE

This study provides prevalence information for feline ophthalmic diseases and could contribute important data for diagnosing, treating and preventing feline ophthalmic diseases in South Korea.

Genetic Aspects of Corneal Sequestra in a Population of Persian, Himalayan and Exotic Cats

Simple Summary

Corneal sequestrum is a common eye disease in Persian, Himalayan and exotic cats. It is a brown stain on the cornea that can be painful and often requires surgery for full recovery. The cause of this disease is unknown. One hypothesis is that genetic factors influence the disease, but there are no data to support this in the scientific literature. In this study, the influence of genetics on this disease was investigated on the basis of clinical and pedigree data from a cattery. Kittens of some dams in this cattery turned out to have a higher risk of corneal sequestra than kittens of other dams, indicating that genetics indeed play a role. The disease also has a high heritability, which implies that by selecting the right breeding animals, breeders can reduce the risk of corneal sequestra in the offspring. DNA analysis of some of the cats from the cattery could not link the disease to a specific region in the DNA, so it is possible that many different genes in different DNA regions are involved in the development of corneal sequestra.

Abstract

Corneal sequestra are ophthalmic lesions that are remarkably common in Persian, Himalayan and exotic cats. In this study, the genetic aspects of this disease were investigated in a population of cats originating from a single cattery. Odds ratios were calculated for parents with affected offspring. The heritability of (owner-reported) corneal sequestra was estimated with a Markov chain Monte Carlo procedure. Well-phenotyped cases and controls were used for a genome-wide association study. Data from 692 cats originating from the cattery, of which 61 were affected, were used. Cats from two specific mothers had significantly higher odds of developing corneal sequestra, but no significant effect of the fathers was found (after correction for the mothers). The heritability of corneal sequestra was estimated to be 0.96. A genome-wide association study with 14 cases and 10 controls did not reveal an associated chromosomal region. The large effect that genetic factors had on the development of corneal sequestra in this study suggests that selective breeding could be an effective way to reduce the prevalence of this condition in these cat breeds.