Equine Atypical Myopathy, also known as Atypical Myoglobinuria, is a frequently fatal condition affecting autumn and/or spring grazing horses. The disease’s clinical signs seem to appear after the occurrence of specific climatic conditions.

The condition was recognised in 1984 and since then, several clinical cases have been described in different countries in Europe. Belgium was first confronted with a major outbreak in 2000. In France, the first cases have been described in autumn 2002. Each year in Ireland, there have been from six to 12 cases diagnosed with perhaps many more occurring but not identified.