Equine Degenerative Myeloencephalopathy in Lusitano Horses

Journal of Veterinary Internal Medicine

C.J. Finno²  R.J. Higgins⁵  M. Aleman²  R. Ofri⁴  S.R. Hollingsworth¹  D.L. Bannasch³  C.M. Reilly⁵ 

[1] Surgical and Radiological Sciences;From the William R. Pritchard Veterinary Medical Teaching Hospital;Population Health and Reproduction;the Koret School of Veterinary Medicine, Hebrew University of Jerusalem, Rehovot, Israel;Departments of Pathology, Microbiology and Immunology

关键词: Electroretinogram;    Equine;    Neuro axonal dystrophy;    Vitamin E;   

DOI  :  10.1111/j.1939-1676.2011.00817.x

来源: Wiley

【 摘 要 】

Abstract

Background

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.

Animals

Fifteen Lusitano horses.

Procedures

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 and Clinical Relevance

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.

【 授权许可】

Unknown   
Copyright © 2011 by the American College of Veterinary Internal Medicine