Grass sickness

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    This article has been edited and approved by Karen Coumbe MRCVS, H&H’s veterinary advisor since 1991.
  • Grass sickness: Signs | Diagnosis | Treatment | Causes | Risk factors | Prevention

    Grass sickness is an often-fatal condition that typically occurs in grazing horses. It was first recognised in Scotland in the early 1900s, yet relatively little is known about the condition.

    The United Kingdom has the highest incidence of grass sickness in the world with cases being more common in spring. Young adult horses, aged between two and seven years, appear to be at the highest risk of the condition, but it can affect horses of any age.