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Oxyuris equi

Oxyuris equi

Oxyuris equi


  • Kingdom Animalia
  • Phylum Nematoda
  • Class Secernentea
  • Order Oxyurida
  • Superfamily Oxyuroidea
  • Family Oxyuridae
  • Genus Oxyuris

Final host

  • Horse, donkey


  • Adults: known as "pin worms" because of the very long tapering tails of mature females. Mature females (up to 10 - 15 cm long) are much larger than mature males (9-12 mm long)
  • The oesophagus has the typical oxyurid oesophageal double bulb
  • The vulva in the female is situated anteriorly and males have caudal alae and a single pinshaped spicule
  • Eggs (80-95 by 40-45 µm) are ovoid, thick-selled, smooth and slightly flattened on one side with a transparent mucoid operculate plug at one end and and contain a late-stage morula or a first larval stage when shed in faeces


  • Direct


  • Caecum, colon, rectum


  • Histophagous and intestinal content


  • Eggs


  • L3 within the egg