Equine degenerative myeloencephalopathy in Lusitano horses.
Abstract: Equine degenerative myeloencephalopathy (EDM) is a neurodegenerative disorder that has been previously associated with low vitamin E concentrations. Objective: To describe the clinical, electrophysiologic, and pathologic features of EDM in a group of related Lusitano horses. Methods: Fifteen Lusitano horses. Methods: Neurologic examinations were conducted, and serum vitamin E concentrations were measured. Three neurologically abnormal horses were further evaluated by ophthalmologic examination, electroretinography, electroencephalography, muscle and nerve biopsies, and post-mortem examination. Results: Six horses appeared neurologically normal, 6 were neurologically abnormal, and 3 had equivocal gait abnormalities. Abnormal horses demonstrated ataxia and paresis. An inconsistent menace response was noted in 4 neurologically abnormal horses and in 1 horse with equivocal findings. All horses had low serum vitamin E concentrations (<1.5 ppm). Ophthalmologic examinations, electroretinograms, electroencephalograms, and muscle and peripheral nerve biopsies were unremarkable in 3 neurologically abnormal horses. At necropsy, major neuropathological findings in these horses were bilaterally symmetric, severe, neuro axonal degeneration in the gracilis, cuneatus medialis, cuneatus lateralis, and thoracicus nuclei and bilaterally symmetric axonal loss and demyelination mainly in the dorsolateral and ventromedial tracts of the spinal cord. A diagnosis of EDM was made based on these findings. Pedigree analysis identified 2 sires among the affected horses. Conclusions: Equine degenerative myeloencephalopathy is a neurodegenerative disorder that causes ataxia and, in severe cases, paresis, in young Lusitano horses. The disease appears to have a genetic basis, and although vitamin E deficiency is a common finding, low serum vitamin E concentrations also may occur in apparently unaffected related individuals.
Copyright © 2011 by the American College of Veterinary Internal Medicine.
Publication Date: 2011-11-19 PubMed ID: 22092640DOI: 10.1111/j.1939-1676.2011.00817.xGoogle 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
- Research Support
- Non-U.S. Gov't
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 article describes an investigation into Equine degenerative myeloencephalopathy (EDM) in Lusitano horses, a disease related to low vitamin E concentrations, causing neurological symptoms. The study identified a genetic basis for the disorder and found that low vitamin E levels could also be present in apparently unaffected horses.
Methods
- A total of 15 Lusitano horses were examined in this study. They underwent neurological examinations, and their serum vitamin E concentrations were measured.
- Out of these, three were observed to have abnormal neurological conditions and were subjected to further tests such as ophthalmologic examination, electroretinography, electroencephalography, muscle and nerve biopsies, and post-mortem examination.
Results
- The horses were categorised based on the neurological examination results: six horses appeared normal, six shown signs of abnormal neurological conditions, while three had ambiguous gait abnormalities.
- The horses with abnormal neurological symptoms were found to demonstrate ataxia and paresis. Moreover, inconsistent menace response was found in four such horses and in one horse with doubtful results.
- All horses in the study showed a deficiency of vitamin E concentration in their serum, even those that appeared neurologically normal.
- The additional tests on the three neurologically abnormal horses did not show any remarkable results.
- However, post-mortem examination uncovered significant neuropathological changes in these horses, such as neuro axonal degeneration in specific parts of the spine and brain and axonal loss and demyelination in the spinal cord. Based on these discoveries, a diagnosis of EDM was made for these horses.
- Pedigree analysis revealed a possible genetic connection, with two sires identified amongst the affected horses.
Conclusion
- The study concludes that equine degenerative myeloencephalopathy (EDM) is a neurodegenerative disorder causing ataxia, and in severe cases, paresis, in young Lusitano horses.
- They found that the disease is likely to have a genetic basis. While vitamin E deficiency is frequently found in these affected horses, low serum vitamin E levels can also be observed in apparently healthy horses from the same pedigree, indicating that there could be more factors at play than just vitamin deficiency in the onset of this disease.
Cite This Article
APA
Finno CJ, Higgins RJ, Aleman M, Ofri R, Hollingsworth SR, Bannasch DL, Reilly CM, Madigan JE.
(2011).
Equine degenerative myeloencephalopathy in Lusitano horses.
J Vet Intern Med, 25(6), 1439-1446.
https://doi.org/10.1111/j.1939-1676.2011.00817.x Publication
Researcher Affiliations
- William R. Pritchard Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California Davis, CA 95616, USA. cjfinno@ucdavis.edu
MeSH Terms
- Animals
- Encephalomyelitis / etiology
- Encephalomyelitis / genetics
- Encephalomyelitis / pathology
- Encephalomyelitis / veterinary
- Female
- Genetic Predisposition to Disease
- Horse Diseases / etiology
- Horse Diseases / genetics
- Horse Diseases / pathology
- Horses
- Male
- Pedigree
- Vitamin E Deficiency / complications
- Vitamin E Deficiency / veterinary
Citations
This article has been cited 14 times.- Powers A, Peek SF, Reed S, Donnelly CG, Tinkler S, Gasper D, Woolard KD, Finno CJ. Equine neuroaxonal dystrophy/degenerative myeloencephalopathy in Gypsy Vanner horses. J Vet Intern Med 2024 May-Jun;38(3):1792-1798.
- Brown KA, Bender SJ, Johnson AL. Clinical and histopathological features in horses with neuroaxonal degeneration: 100 cases (2017-2021). J Vet Intern Med 2024 Jan-Feb;38(1):431-439.
- Ma Y, Peng S, Donnelly CG, Ghosh S, Miller AD, Woolard K, Finno CJ. Genetic polymorphisms in vitamin E transport genes as determinants for risk of equine neuroaxonal dystrophy. J Vet Intern Med 2024 Jan-Feb;38(1):417-423.
- Bedenice D, Johnson AL. Neurologic conditions in the sport horse. Anim Front 2022 Jun;12(3):37-44.
- Donnelly CG, Burns E, Easton-Jones CA, Katzman S, Stuart R, Cook SE, Finno CJ. Safety and efficacy of subcutaneous alpha-tocopherol in healthy adult horses. Equine Vet Educ 2021 Apr;33(4):215-219.
- Bitschi ML, Bagó Z, Rosati M, Reese S, Goehring LS, Matiasek K. A Systematic Approach to Dissection of the Equine Brain-Evaluation of a Species-Adapted Protocol for Beginners and Experts. Front Neuroanat 2020;14:614929.
- Hales EN, Esparza C, Peng S, Dahlgren AR, Peterson JM, Miller AD, Finno CJ. Genome-Wide Association Study and Subsequent Exclusion of ATCAY as a Candidate Gene Involved in Equine Neuroaxonal Dystrophy Using Two Animal Models. Genes (Basel) 2020 Jan 10;11(1).
- Marquardt SA, Wilcox CV, Burns EN, Peterson JA, Finno CJ. Previously Identified Genetic Variants in ADGRL3 Are not Associated with Risk for Equine Degenerative Myeloencephalopathy across Breeds. Genes (Basel) 2019 Sep 5;10(9).
- Burns EN, Finno CJ. Equine degenerative myeloencephalopathy: prevalence, impact, and management. Vet Med (Auckl) 2018;9:63-67.
- Estell K, Spriet M, Phillips KL, Aleman M, Finno CJ. Current dorsal myelographic column and dural diameter reduction rules do not apply at the cervicothoracic junction in horses. Vet Radiol Ultrasound 2018 Nov;59(6):662-666.
- Brown JC, Valberg SJ, Hogg M, Finno CJ. Effects of feeding two RRR-α-tocopherol formulations on serum, cerebrospinal fluid and muscle α-tocopherol concentrations in horses with subclinical vitamin E deficiency. Equine Vet J 2017 Nov;49(6):753-758.
- Finno CJ, Kaese HJ, Miller AD, Gianino G, Divers T, Valberg SJ. Pigment retinopathy in warmblood horses with equine degenerative myeloencephalopathy and equine motor neuron disease. Vet Ophthalmol 2017 Jul;20(4):304-309.
- Finno CJ, Valberg SJ, Shivers J, D'Almeida E, Armién AG. Evidence of the Primary Afferent Tracts Undergoing Neurodegeneration in Horses With Equine Degenerative Myeloencephalopathy Based on Calretinin Immunohistochemical Localization. Vet Pathol 2016 Jan;53(1):77-86.
- Finno CJ, Famula T, Aleman M, Higgins RJ, Madigan JE, Bannasch DL. Pedigree analysis and exclusion of alpha-tocopherol transfer protein (TTPA) as a candidate gene for neuroaxonal dystrophy in the American Quarter Horse. J Vet Intern Med 2013 Jan-Feb;27(1):177-85.
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
