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Bulletin #2112, It’s a Sneeze, It’s a Wheeze, It’s … Gapeworms!

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It’s a Sneeze, It’s a Wheeze, It’s … Gapeworms!

By Anne Lichtenwalner, DVM PhD, University of Maine Extension

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free-range poultrySyngamus tracheae, or the “gapeworm,” is one of several worms that can live in your chicken’s respiratory tract. This worm lives in the trachea, and causes coughing, wheezing and open-mouth breathing (“gapes”).

Birds get infected by eating the worm eggs from feces-contaminated ground, or by eating earthworms infested by the gapeworm larvae. In either case, the gapeworms mature and migrate within the chicken, ending up in the respiratory tract. They live in the trachea, laying eggs, which are coughed up by the chicken, swallowed, and passed out in the feces. Either another bird, or an earthworm, eats the eggs; then the cycle starts again.

How can you tell if it is gapeworms, and not a viral or bacterial disease? A fecal examination at the vet’s office may do it, or you can send a fecal sample to the University of Maine Animal Health Lab. Alternatively, you could try parting the neck feathers, using a flashlight in a darkened room to transilluminate the trachea, and try to visualize these bright red, 1/2-inch to 2-inch long worms through the thin skin of the hen (see photo of a turkey trachea containing gapeworms below).

Turkey necropsy showing gapeworms

Trachea at necropsy, opened up to show bright red gapeworms (approx. 1/2 inch long).


Proper treatment can be done with the help of your vet. Remember, not all wormers kill all worms. Proper diagnosis will help you find the right product to use, and to use it in the right way. Remember that using drugs of any kind in livestock raised for food must be done exactly according to label directions, or following your veterinarian’s instructions.

How can you prevent gapeworm? If there have been birds of any kind on your land (including wild ones, such as turkeys) then gapeworms and other parasites may be a problem for you.

  • Consider keeping hens in “biosecure” coops and henyards that keep wild birds out by use of netting and overhead covers.
  • Using a sand or concrete layer in the henyard can minimize the risk of infection by either contact with contaminated soil, or with earthworms.
  • Many interesting coop designs are available on the internet. If you want to use a chicken “tractor” to allow your chickens access to pasture, please be sure to move it frequently enough that they are never on bare or muddy ground.

Information in this publication is provided purely for educational purposes. No responsibility is assumed for any problems associated with the use of products or services mentioned. No endorsement of products or companies is intended, nor is criticism of unnamed products or companies implied.

© 2013
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