Changes

==Aetiology==

==Aetiology==

EPM results from infection of the CNS by the apicomplexan parasite [[Sarcocystis|''Sarcocystis neurona'']] or, less frequently, its close relative ''Neospora hughesi''.<ref>Dubey, J.P, Lindsay, D.S, Saville, W.J, Reed, S.M, Granstrom, D.E, Speer, C.A (2001)A review of ''Sarcocystis neurona'' and equine protozoal myeloencephalitis (EPM). ''Vet Parasitol'', 95:89-131. In: Pusterla, N, Wilson, W.D, Conrad, P.A, Barr, B.C, Ferraro, G.L, Daft, B.M, Leutenegger, C.M (2006) Cytokine gene signatures in neural tissue of horses with equine protozoal myeloencephalitis or equine herpes type 1 myeloencephalopathy.  ''Vet Rec'', Sep 9:''Papers & Articles''.</ref><ref>Wobeser, B.K, Godson, D.L, Rejmanek, D, Dowling, P (2009) Equine protozoal myeloencephalitis caused by ''Neospora hughesi'' in an adult horse in Saskatchewan.  ''Can Vet J'', 50(8):851-3.</ref>  These protozoans develop within neurons<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>  causing immediate or inflammatory-mediated neuronal damage.  The organisms migrate randomly through the brain and spinal cord causing asymmetrical lesions of grey and white matter and thus multifocal lower and upper motor neuron deficits.<ref name="Pasq">Pasquini, C, Pasquini, S, Woods, P (2005) '''Guide to Equine Clinics Volume 1: Equine Medicine''' (Third edition), ''SUDZ Publishing'', 245-250.</ref>

EPM results from infection of the CNS by the apicomplexan parasite [[Sarcocystis|''Sarcocystis neurona'']] or, less frequently, its close relative [[Neospora|''Neospora hughesi'']].<ref>Dubey, J.P, Lindsay, D.S, Saville, W.J, Reed, S.M, Granstrom, D.E, Speer, C.A (2001)A review of ''Sarcocystis neurona'' and equine protozoal myeloencephalitis (EPM). ''Vet Parasitol'', 95:89-131. In: Pusterla, N, Wilson, W.D, Conrad, P.A, Barr, B.C, Ferraro, G.L, Daft, B.M, Leutenegger, C.M (2006) Cytokine gene signatures in neural tissue of horses with equine protozoal myeloencephalitis or equine herpes type 1 myeloencephalopathy.  ''Vet Rec'', Sep 9:''Papers & Articles''.</ref><ref>Wobeser, B.K, Godson, D.L, Rejmanek, D, Dowling, P (2009) Equine protozoal myeloencephalitis caused by ''Neospora hughesi'' in an adult horse in Saskatchewan.  ''Can Vet J'', 50(8):851-3.</ref>  These protozoans develop within neurons<ref name="Furr">Furr, M (2010) ''Equine protozoal myeloencephalitis'' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), ''Saunders'', Chapter 12.</ref>  causing immediate or inflammatory-mediated neuronal damage.  The organisms migrate randomly through the brain and spinal cord causing asymmetrical lesions of grey and white matter and thus multifocal lower and upper motor neuron deficits.<ref name="Pasq">Pasquini, C, Pasquini, S, Woods, P (2005) '''Guide to Equine Clinics Volume 1: Equine Medicine''' (Third edition), ''SUDZ Publishing'', 245-250.</ref>

==Epidemiology==

==Epidemiology==