|Twenty-five WB horses from one farm underwent complete neurologic and ophthalmic examinations and serum Î±-TP concentrations were assessed.
Two of the most severely ataxic horses were euthanized and postmortem examinations performed.
Alpha-TP deficiency was widespread on this farm (22 of 25 horses).
Eleven of 25 horses were clinically normal (age range 2â€“12 years), one had signs of EMND (6 years of age), 10 had signs of ataxia consistent with NAD/EDM (1â€“10 years), and two of these were postmortem confirmed concurrent NAD/EDM and EMND.
A pigment retinopathy characterized by varying amounts of granular dark pigment in the tapetal retina was observed in four clinically apparent NAD/EDM horses (two postmortem confirmed concurrent NAD/EDM and EMND) and one horse with clinical signs of EMND.
A pigment retinopathy can be present in young Î±-TP-deficient Warmblood horses with clinical signs of EMND as well as those with signs of NAD/EDM.
Source: Finno, C. J., Kaese, H. J., Miller, A. D., Gianino, G., Divers, T. and Valberg, S. J. (2017), Pigment retinopathy in warmblood horses with equine degenerative myeloencephalopathy and equine motor neuron disease. Veterinary Ophthalmology, 20: 304â€“309. doi: 10.1111/vop.12417