Article Text

Download PDFPDF
Update on the cause of equine atypical myopathy
  1. Sonia Gonzalez-Medina, CertAVP(EM), MRCVS
  1. Centre of Preventive Medicine, Animal Health Trust, Newmarket, UK
  1. e-mail: sonia.gonzalez-medina{at}

Statistics from

ATYPICAL myopathy was first recognised in grazing horses in 1939 in East Scotland and first reported in the literature in 1942 (Bowen 1942). The condition was named acute myopathy or atypical myoglobinuria due to clinical signs seen in the first identified cases. Early reports described recumbent and weak horses that often died within the first 12 to 72 hours. Suspected cases sporadically occurred in several countries such as the USA, Canada and Australia, although it was known as seasonal pasture disease in these locations. The first major outbreak, which raised awareness of the condition worldwide, occurred in Germany in 1995. Since 2000, numbers of outbreaks and affected animals increased considerably in central Europe, triggering the beginning of epidemiological investigations into the mechanisms of disease and methods for its prevention.


The University of Liege in Belgium established an informal epidemiosurveillance network known as the Atypical Myopathy Alert Group (AMAG) which in 2006 expanded its national recording of cases to all European cases (Fig 1). Currently, this network consists of equine veterinarians worldwide, national epidemiological networks, and other collaborators such as universities. AMAG's aim is to exchange information about the occurrence of outbreaks of this disease (Fig 2) and to initiate collaborative research.

FIG 1:

Number of atypical myopathy cases reported to the Atypical Myopathy Alert Group from 2006 to 2013

FIG 2:

Location of European cases of atypical myopathy from 2006 to 2013. Data from the Atypical Myopathy Alert Group


Environmental toxins were considered as potential causative agents for atypical myopathy from the …

View Full Text

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.