Breed predispositions to congenital and juvenile cataracts in horses at two academic institutions.
Abstract: Determination of horse breeds predisposed to congenital and juvenile cataracts will enable investigations into potential genetic mechanisms for cataracts in horses. Objective: To investigate horse breed predispositions to congenital and juvenile cataracts in two academic referral populations. Methods: Retrospective case series. Methods: Medical record identification of horses diagnosed with congenital or juvenile cataracts at the Cornell University Equine Hospital (2000-2022) and the University of California-Davis (UCD) Large Animal Clinic (1990-2021). Signalment, examination findings and treatments were recorded. Descriptive statistics were performed, and breed over-representations were determined using Chi-squared or Fisher's exact tests. Results: Thirty-one (Cornell) and 70 (UCD) horses with congenital or juvenile cataracts were identified, for a total of 101 affected horses. Seventy-eight horses were affected bilaterally and 23 were affected unilaterally, for a total of 179 affected eyes. Standardbreds were significantly over-represented at both institutions, comprising 32.5% of congenital/juvenile cataract cases and 10% of the equine hospital population at Cornell (p < 0.001) and 4.3% of cataract cases and 1.3% of the equine hospital population at UCD (p = 0.03). Thoroughbreds were under-represented for congenital and juvenile cataracts at both institutions (p = 0.03 Cornell, p = 0.01 UCD). Conclusions: Retrospective study, potential for selection bias. Conclusions: The over-representation of the Standardbred breed for congenital and juvenile cataracts at two institutions suggests an underlying genetic basis in the breed. Future genetic and genomic studies are warranted to investigate heritable cataracts in Standardbred horses. Unassigned: Die Bestimmung von Pferderassen, die für angeborenen und jugendlichen Katarakt prädisponiert sind, wird die Erforschung möglicher genetischer Mechanismen für Katarakte bei Pferden ermöglichen. ZIEL: Ziel dieser Studie war es, die Prädisposition von Pferderassen für kongenitale und juvenile Katarakte in zwei akademischen Überweisungspopulationen zu untersuchen. Methods: Retrospektive Fallserie. Methods: Identifizierung der Krankenakten von Pferden, bei denen im Cornell University Equine Hospital (2000–2022) und in der University of California‐Davis (UCD) Large Animal Clinic (1990–2021) ein angeborener oder juveniler Katarakt diagnostiziert wurde. Signalement, Untersuchungsergebnisse und Behandlungen wurden aufgezeichnet. Es wurden deskriptive Statistiken erstellt und die Überrepräsentation von Rassen wurde mit Hilfe von Chi‐Quadrat‐ oder Exakter Fisher‐Test ermittelt. Unassigned: Einunddreißig (Cornell) und 70 (UCD) Pferde mit kongenitalem oder juvenilem Katarakt wurden identifiziert, insgesamt also 101 betroffene Pferde. Achtundsiebzig Pferde waren beidseitig und 23 einseitig betroffen, insgesamt also 179 betroffene Augen. Standardbreds waren in beiden Einrichtungen deutlich überrepräsentiert: 32.5% der Fälle von angeborenem/jugendlichem Katarakt und 10% der Pferdekrankenhauspopulation in Cornell (p < 0.001) und 4.3% der Kataraktfälle und 1.3% der Pferdekrankenhauspopulation in UCD (p = 0.03). Vollblüter waren bei kongenitalem und juvenilem Katarakt in beiden Einrichtungen unterrepräsentiert (p = 0.03 Cornell, p = 0.01 UCD). Unassigned: Retrospektive Studie, Möglichkeit der Verzerrung durch Selektion. Unassigned: Die Überrepräsentation der Rasse Standardbred für kongenitale und juvenile Katarakte in zwei Einrichtungen lässt auf eine genetische Grundlage bei der Rasse schließen. Künftige genetische und genomische Studien zur Untersuchung der vererbbaren Katarakte bei Standardbred‐Pferden sind gerechtfertigt.
© 2023 EVJ Ltd.
Publication Date: 2023-12-14 PubMed ID: 38095155DOI: 10.1111/evj.14034Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
- 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 was aimed at studying the predisposition of different horse breeds to congenital and juvenile cataracts in two academic referral populations to help uncover potential genetic causes of these cataracts. The findings revealed that Standardbred horses are over-represented in the cases of these cataracts suggesting that there might be an underlying genetic basis in this breed.
Objective
The research aimed to identify horse breeds that show a predisposition to developing congenital, existing from birth, and juvenile, typically occurring during youth, cataracts. Insight into these predispositions might serve as a basis for further genetic investigation into the disease.
Methodology
- The study was retrospective, studying past cases, and was conducted in two academic institutions – the Cornell University Equine Hospital and the University of California-Davis Large Animal Clinic.
- Medical records of horses diagnosed with these types of cataracts between 2000 and 2022 at Cornell and between 1990 and 2021 at UCD were examined. Information including signalment (a horse’s characteristics), examination findings, and treatments, was recorded.
- Various statistical analyses, Chi-square or Fisher’s exact tests, were employed to identify over or under-representation of certain horse breeds in the cataract cases.
Results
- The study identified 31 cases of congenital or juvenile cataracts at Cornell and 70 at UCD, making a cumulative 101 affected horses.
- The majority (78) of the horses were affected in both eyes (bilaterally) while 23 were affected in one eye (unilaterally), making a total of 179 affected eyes.
- Standardbred horses were highly over-represented in the cataract cases at both institutions. They accounted for 32.5% of the cataract cases at Cornell while only making up 10% of the equine hospital population and 4.3% of the cataract cases at UCD while only making up 1.3% of the equine hospital population.
- Thoroughbreds, on the other hand, were under-represented in both the institutions.
Conclusions
- Though results revealed the Standardbred breed’s over-representation in cases of congenital and juvenile cataracts at both institutions, the research technique comprised a retrospective study, therefore, a potential for selection bias exists.
- Nevertheless, the over-representation suggests an underlying genetic basis for these cataracts in the Standardbred breed. This warrants future genetic and genomic studies for further investigation into heritable cataracts in this breed.
Cite This Article
APA
Plotsker NM, Bellone RR, Ledbetter EC, Irby NL, Good KL, Knickelbein KE.
(2023).
Breed predispositions to congenital and juvenile cataracts in horses at two academic institutions.
Equine Vet J, 56(5), 1041-1049.
https://doi.org/10.1111/evj.14034 Publication
Researcher Affiliations
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
- Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, Davis, California, USA.
- Veterinary Genetics Laboratory, School of Veterinary Medicine, University of California, Davis, Davis, California, USA.
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
- Department of Surgical and Radiological Sciences, School of Veterinary Medicine, University of California, Davis, Davis, California, USA.
- Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, New York, USA.
MeSH Terms
- Animals
- Horses / genetics
- Horse Diseases / genetics
- Horse Diseases / congenital
- Cataract / veterinary
- Cataract / genetics
- Cataract / congenital
- Retrospective Studies
- Genetic Predisposition to Disease
- Male
- Female
References
This article includes 21 references
- McMullen RJ, Gilger BC. Keratometry, biometry and prediction of intraocular lens power in the equine eye.. Vet Ophthalmol 2006;9(5):357–360.
- Townsend WM, Jacobi S, Bartoe JT. Phacoemulsification and implantation of foldable +14 diopter intraocular lenses in five mature horses: intraocular lenses in mature horses.. Equine Vet J 2012;44(2):238–243.
- Meister U, Görig C, Murphy CJ, Haan H, Ohnesorge B, Boevé MH. Intraocular lens power calculation for the equine eye.. BMC Vet Res 2018;14(1):123.
- Edelmann ML, McMullen R, Stoppini R, Clode A, Gilger BC. Retrospective evaluation of phacoemulsification and aspiration in 41 horses (46 eyes): visual outcomes vs. age, intraocular lens, and uveitis status.. Vet Ophthalmol 2014;17(Suppl 1):160–167.
- Brooks DE, Plummer CE, Carastro SM, Utter ME. Visual outcomes of phacoemulsification cataract surgery in horses: 1990‐2013.. Vet Ophthalmol 2014;17(Suppl 1):117–128.
- Baxter BL. Effect of visual deprivation during postnatal maturation on the electroencephalogram of the cat.. Exp Neurol 1966;14(2):224–237.
- Hubel DH, Wiesel TN. The period of susceptibility to the physiological effects of unilateral eye closure in kittens.. J Physiol 1970;206(2):419–436.
- Birch EE, Stager DR. The critical period for surgical treatment of dense congenital unilateral cataract.. Invest Ophthalmol Vis Sci 1996;37(8):1532–1538.
- Mellersh CS, Pettitt L, Forman OP, Vaudin M, Barnett KC. Identification of mutations in HSF4 in dogs of three different breeds with hereditary cataracts.. Vet Ophthalmol 2006;9(5):369–378.
- Eriksson R. Hereditary aniridia with secondary cataract in horses.. Nord Vet Med 1955;7:773–779.
- Beech J, Irby N. Inherited nuclear cataracts in the Morgan horse.. J Hered 1985;76:371–372.
- Joyce JR, Martin JE, Storts RW, Skow L. Iridial hypoplasia (aniridia) accompanied by limbic dermoids and cataracts in a group of related Quarterhorses.. Equine Vet J 2010;22(S10):26–28.
- McCormick KA, Ward D, Newkirk KM. Aniridia in two related Tennessee walking horses.. Case Rep Vet Med 2013;2013:1–4.
- Yuan L, Yao H, Xu Y, Chen M, Deng J, Song Y. CRISPR/Cas9‐mediated mutation of αA‐Crystallin gene induces congenital cataracts in rabbits.. Invest Ophthalmol Vis Sci 2017;58(6):BIO34–BIO41.
- Hassan AY, Yousaf S, Levin MR, Saeedi OJ, Riazuddin S, Alexander JL. Novel homozygous missense variant in GJA3 Connexin domain causing congenital nuclear and cortical cataracts.. Int J Mol Sci 2021;23(1):240.
- Andersson LS, Wilbe M, Viluma A, Cothran G, Ekesten B, Ewart S. Equine multiple congenital ocular anomalies and silver coat colour result from the pleiotropic effects of mutant PMEL.. PLoS ONE 2013;8(9):e75639.
- Beech J, Aguirre G, Gross S. Congenital nuclear cataracts in the Morgan horse.. J Am Vet Med Assoc 1984;184(11):1363–1365.
- Pinard CL, Basrur PK. Ocular anomalies in a herd of Exmoor ponies in Canada: ocular anomalies in a herd of exmoor ponies.. Vet Ophthalmol 2011;14(2):100–108.
- Hurn SD, Turner AG. Ophthalmic examination findings of Thoroughbred racehorses in Australia.. Vet Ophthalmol 2006;9(2):95–100.
- Shiels A, Hejtmancik JF. Inherited cataracts: genetic mechanisms and pathways new and old.. Exp Eye Res 2021;209:108662.
- Millichamp D. Cataract phacofragmentation in horses.. Vet Ophthalmol 2000;3(2–3):157–164.
Use Nutrition Calculator
Check if your horse's diet meets their nutrition requirements with our easy-to-use tool Check your horse's diet with our easy-to-use tool
Talk to a Nutritionist
Discuss your horse's feeding plan with our experts over a free phone consultation Discuss your horse's diet over a phone consultation
Submit Diet Evaluation
Get a customized feeding plan for your horse formulated by our equine nutritionists Get a custom feeding plan formulated by our nutritionists
