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Abscess in Horses

Abscess in Horses


An abscess is an accumulation of pus (dead white blood cells) that forms a lump internally or externally on your horse’s body. It occurs as a result of an infection, as the white blood cells assemble to fight off a foreign antigen, then subsequently die, becoming walled off in a capsule as the body attempts to isolate the infection. This lump is usually accompanied by inflammation and can be painful, due to the buildup of pressure. As time passes, the abscess can rupture, releasing pus.


Symptoms and Types


  • Slight swelling under the skin
  • A firm lump that may be tender or hot to the touch
  • Secretion of pus
  • Lameness




  • Penetration of the skin surface with a foreign object
  • A wound
  • A nail in the hoof
  • Infection
  • Strangles (respiratory bacterial infection caused by Streptococcus equi)




Upon examining the affected area, your veterinarian should easily be able to determine whether the wound is an abscess. The vet may then order blood tests to check for other infections. Many times, minor things will get into or under the skin and become infected, causing an abscess.