A retrospective survey of equine ocular diseases evaluated at a referral hospital in Ontario (2011 to 2021).
Abstract: Our objective was to investigate the demographics and prevalence of ocular disease in a large referral population of horses in Ontario over a 10-year period. Unassigned: A retrospective analysis of medical records for 283 horses evaluated by Board-certified veterinary ophthalmologists at the Ontario Veterinary College (Guelph, Ontario) was conducted. Signalment and ocular disease were recorded. Unassigned: The 3 most common ocular abnormalities identified were uveitis (43.7%, 123 horses), ulcerative keratitis (42.0%, 119 horses), and cataract (25.1%, 71 horses). Uveitis was most often secondary to other ocular disease. Middle-aged horses (5 to 15 y) had a lower proportion of ulcerative keratitis than young horses (0 to 4 y) and older horses (16 to 35 y) (P = 0.015). Older horses were more likely to be diagnosed with glaucoma than were young and middle-aged horses (P = 0.022). Thoroughbred was the most common breed referred. Warmbloods were significantly less likely to receive a diagnosis of uveitis compared to other breeds (P = 0.05). Adnexal disease and neoplasia were both more prevalent in draft breeds compared to other breeds (P < 0.001). Unassigned: For the first time, the most prevalent ocular diseases and breeds referred for ocular disease are reported for horses in eastern Canada. This study serves as a reference for practitioners and sets a baseline for future studies. Une enquête rétrospective sur les maladies oculaires équines évaluées dans un hôpital de référence en Ontario (2011 à 2021). Unassigned: Notre objectif était d’étudier la démographie et la prévalence des maladies oculaires dans une large population de chevaux référés en Ontario sur une période de 10 ans. Unassigned: Une analyse rétrospective des dossiers médicaux de 283 chevaux évalués par des ophtalmologistes vétérinaires certifiés du Ontario Veterinary College (Guelph, Ontario) a été réalisée. Le signalement et les maladies oculaires ont été enregistrées. Unassigned: Les 3 anomalies oculaires les plus fréquemment identifiées étaient l’uvéite (43,7 %, 123 chevaux), la kératite ulcéreuse (42,0 %, 119 chevaux) et la cataracte (25,1 %, 71 chevaux). L’uvéite était le plus souvent secondaire à une autre maladie oculaire. Les chevaux d’âge moyen (5 à 15 ans) présentaient une proportion plus faible de kératite ulcéreuse que les jeunes chevaux (0 à 4 ans) et les chevaux plus âgés (16 à 35 ans) (P = 0,015). Les chevaux plus âgés étaient plus susceptibles d’être diagnostiqués avec un glaucome que les chevaux jeunes et d’âge moyen (P = 0,022). Le Thoroughbred était la race la plus couramment mentionnée. Les chevaux de race Warmblood étaient significativement moins susceptibles de recevoir un diagnostic d’uvéite par rapport aux autres races (P = 0,05). Les maladies des annexes de l’œil et les néoplasies étaient toutes deux plus répandues chez les races de trait que chez les autres races (P < 0,001). Unassigned: Pour la première fois, les maladies oculaires les plus répandues et les races référées pour maladies oculaires sont décrites chez les chevaux de l’est du Canada. Cette étude sert de référence pour les praticiens et établit une base pour les études futures.(Traduit par Dr Serge Messier).
Copyright and/or publishing rights held by the Canadian Veterinary Medical Association.
Publication Date: 2025-03-12 PubMed ID: 40070935PubMed Central: PMC11891807
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- Journal Article
Summary
This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.
This research investigated the common eye diseases in horses referred to Ontario Veterinary College over a decade. The study found that uveitis, ulcerative keratitis, and cataracts were the prevalent ocular conditions, where older and younger horses were more likely to be diagnosed with different eye diseases. Thoroughbreds were the most commonly referred breeds, with some breed-specific disease trends observed.
Key Objective
- The researchers aimed to study the prevalence and key demographic trends of eye diseases in a large population of horses over a ten-year period (2011 to 2021).
Methodology
- A retrospective analysis of medical records of 283 horses was performed. These horses were evaluated by Board-certified veterinary ophthalmologists at Ontario Veterinary College.
- The breed of the horses and the nature of their eye diseases were recorded for the study.
Major Findings
- Uveitis (in 43.7%, 123 horses), ulcerative keratitis (in 42.0%, 119 horses), and cataract (in 25.1%, 71 horses) were observed to be the most common ocular abnormalities in horses.
- Uveitis was commonly a secondary outcome of other eye diseases.
- Middle-aged horses (5 to 15 years old) had a lower rate of ulcerative keratitis in comparison to young horses (0 to 4 years old) and older horses (16 to 35 years old).
- Older horses were more likely to get diagnosed with glaucoma than young and middle-aged horses.
- Among all the breeds, Thoroughbreds were the most common ones referred to the hospital. Warmbloods were significantly less likely to get diagnosed with uveitis compared to other breeds.
- Adnexal diseases and neoplasia were more common in draft horse breeds.
Significance of the Study
- This research presents the first report on the most common ocular diseases and breeds referred for eye diseases in horses in the eastern part of Canada.
- It provides a useful reference point for veterinary practitioners and paves the way for future studies on this subject.
Cite This Article
APA
Ing ST, Pinard CL, James-Jenks EM, Leis ML.
(2025).
A retrospective survey of equine ocular diseases evaluated at a referral hospital in Ontario (2011 to 2021).
Can Vet J, 66(3), 308-317.
Publication
Researcher Affiliations
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4 (Ing, Leis); Ontario Veterinary College, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1 (Pinard, James-Jenks).
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4 (Ing, Leis); Ontario Veterinary College, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1 (Pinard, James-Jenks).
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4 (Ing, Leis); Ontario Veterinary College, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1 (Pinard, James-Jenks).
- Western College of Veterinary Medicine, University of Saskatchewan, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4 (Ing, Leis); Ontario Veterinary College, University of Guelph, 50 Stone Road East, Guelph, Ontario N1G 2W1 (Pinard, James-Jenks).
MeSH Terms
- Animals
- Horses
- Horse Diseases / epidemiology
- Retrospective Studies
- Ontario / epidemiology
- Eye Diseases / veterinary
- Eye Diseases / epidemiology
- Female
- Male
- Prevalence
- Hospitals, Animal
- Uveitis / veterinary
- Uveitis / epidemiology
- Referral and Consultation
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