


Eye Worms

Oxyspiruriasis is an infection with Oxyspirura mansoni, an eyeworm that is a type of nematode. It deposits its eggs in the chicken's eye, which get passed down through the tear ducts, swallowed, and ejected from the body through the feces.

Infected birds can often be seen scratching at their eyes, possibly causing themselves to scratch their eye resulting in an infection. Chickens' eyelids often stick together with white cheesy-looking material. Without treatment, the chicken will eventually loose their eyesight in the infested eye.

Chickens become infected with O. mansoni through ingestion of infected cockroaches (which act as intermediate hosts), or contaminated soil, feed, or bedding with feces from an infected chicken. Once consumed by the chicken, the larvae move about freely within their body, where they migrate up the esophagus to the mouth, nasolacrimal duct, and into their eye. O. mansoni remain in the eye until they mature where they lay their eggs and begin the cycle again. Several wild birds serve as reservoirs for O. mansoni, including black birds, pigeons, bobolinks, blue jays, and loggerhead shrikes.


Bird seen scratching at eye
Nasal discharge
Head drooping
Partially or fully closed eyes
Loss in appetite
Signs of irritation


  • History
  • Clinical signs
  • Physical exam


10% tetramisole2-3 drops into infected eyes or administering orally at a dose of 40 mg/kg BW(Mitterpak et al. 1972)
5% cresol solution1-2 drops placed in the lacrimal sac of the eye; followed by irrigation of the eye with sterile water to wash out remaining solution and any debris
Physical removal of the wormsUsing a local anesthetic and lifting the nictitating membrane
Solution of 0.5% iodine or 0.5%

Administered into the eye with a syringe following applying a local anesthetic, 5% exylocaine(Vellayan et al., 2012).


  • Perform daily health checks on birds and make note of any unusual behaviors
  • Biosecurity
  • Strict sanitary practices

Scientific References

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