Gapeworm, Syngamus trachea, is a parasitic worm that can result in the death of a chicken. More normally found in game birds, gape worms infect the trachea, making it hard for the chicken to breathe and to eat.
Gape Worms, also known as Red Worms and Forked Worms, are normally ingested in larvae form, either through direct feeding, or through the consumption of earth worms, snails or slugs which are caring the gapeworm. As the larvae grow the trachea becomes obstructed. Gapeworms that develop outside of a host can also be ingested by a chicken, although this is more uncommon as the parasite is easily killed, even by sunlight.
The gapeworm themselves are bright red, hence Red Worms, with the male measuring up to 6mm, the female is considerably larger. Once inside the chicken, the male and female then join in a Y-shape, hence Forked Worms.
The first sign of gapeworm normally comes when the chickens fail to eat, and cough a lot, and stretch their necks in an effort to get air into their lungs. Additionally a chicken may also have their eyes closed for most of the day. If a close examination is undertaken there will also likely to be signs of inflammation within the trachea. If the problem though is not dealt with quickly suffocation could be the end result. Gapeworm though normally proves to be more of an issue in young birds, and death is more common than in adults.
Gape worm is more common in birds that are allowed to run wild as confined breeding normally comes with regular cleaning programs for the chicken’s environment. The use of some insecticides will kill off the hosts that can transport the gapeworm larvae.
There are a few different treatment options for gapeworm, although most are only used on more expensive birds, otherwise they are not really cost effective. The use of Thiabendazole has been used successfully on pheasants when added to their feed. Levamisole and Fenbedazole are effective when added to the chicken’s drinking water. Treatments available will often vary in effectiveness depending on how long the infection has been present, and careful study should be undertaken before use.
As with any infection prevention is often a lot better than cure, and where possible chickens should be housed in the cleanest possible environments. As a parasite the gapeworm can prove to be deadly but treatment is available and effective.