The most distinctive feature of this nematode is that males and females are joined together in a state of permanent copulation forming a Y shape
Thicker end is the cranial and the narrower end is the caudal
Macroscopic view of male syngamus trachea
Operculum -a rounded plate that seals the mouth of the shell of some gastropod mollusks when the animal's body is inside
Tran Mode: Ingestion (per os), Ingestion of Intermediate or Paratenic Host
In preparasitic the embryo develops into an infective L3 in the egg. In parasitic phase, this involves the acquiring of infection by the definitive hosts.
Young birds are most severely affected with migration of larvae and adults through the lungs causing catarrhal tracheitis, asphyxiation and pneumonia due to accumulation of large quantity of mucus. lymphoid nodules form at the point of attachment of the worms in the bronchi and trachea due to to permanent attachment of male worm to the tracheal wall throughout the duration of its life. They also appear as bloodsuckers.The female worms can detach and reattach from time to time in order to obtain a more supply of food
Accumulations of mucus cause the affected bird to shake its head, cough, extend its neck and make gaping motions. Chicks, goslings and pheasants are the most susceptible. Turkeys may be infected at all ages and may be dangerous carriers of the disease.
Subclinical infections with few worms may be confirmed at necropsy by finding copulating adults worms, 10 to 20 mm long, in the trachea and also by finding the characteristic eggs in the feces of infected birds. Appropriate clinical signs/history Fecal flotation - egg 90 X 50 microns with small, thick bipolar end plugs, can be found unembryonated in fresh feces.
Tranmission Mode of syngamus trachea is by Ingestion of egg with L3 or hatched larvae. Or by ingestion of Intermediate or Paratenic Host
Leyte Normal UniversityTacloban City<br />Syngamus trachea<br />(Gapeworms in fowl)<br />Presented by:<br />Jenelyn P. Cadion<br />BS Biology 3<br />
Hosts<br /><ul><li>Definitive hosts of Syngamus tracheaare chickens, turkeys, geese, guinea fowl, pheasants, peafowl, quail, and other birds of all ages
Intermediate or paratenichosts include earthworms, snails, (Planorbariuscorneus, Bithynia tentaculata), or slugs, where it encysted.</li></li></ul><li>Life cycle<br /><ul><li>Has preparasitic and parasitic phases
In preparasitic phase, L3s develop inside the eggs at which time they may hatch.
The parasitic phase involves substantial migration in the definitive host to reach the predilection site.</li></li></ul><li>Life cycle<br />Infection may occur in one of three ways. <br />1. By ingestion of an egg containing an L3 (A).2. By ingestion of the hatched L3 (B). 3. By ingestion of a transport host containing encapsulated L3s (C). <br />
<ul><li>Following ingestion, the L3s will be in the duodenum (D) of the final host, molt, and pair off.
They penetrate the intestine and travel first to the liver and then to the lungs (E) via the bloodstream. </li></li></ul><li><ul><li>Adult males and females pair off move up to the trachea and begin copulation in the bronchi and trachea (F).
Eggs escape from the vulva under the bursa of the permanently attached male and are carried up the trachea in the excess mucus produced in response to infection. </li></li></ul><li><ul><li>They are then swallowed and passed in the feces, completing the cycle.
Eggs are passed in the feces of infected birds. Unlike other strongyloids, S. trachea larva develops within the egg until it reaches the L3 stage. </li></li></ul><li>Prepatent period<br /><ul><li>The prepatent period is approximately two weeks with a range of 12-17 days.
Various reports have shown that adults may survive for
approximately 98 days in guinea fowl.</li></li></ul><li>Pathogenesis<br /><ul><li>causes catarrhal tracheitis, asphyxiation and pneumonia
lymphoid nodules form at the point of attachment of the worms in the bronchi and trachea.
Birds infected with gapeworms show signs of weakness and emaciation, usually spend much of their time with eyes closed and head drawn back against the body</li></li></ul><li>
Diagnosis<br /><ul><li>Necropsy by finding copulating adults worms, 10 to 20 mm long, in the trachea and also by finding the characteristic eggs in the feces of infected birds.
Fecal flotation - egg 90 X 50 microns with small, thick bipolar end plugs, unembryonated in fresh feces. </li></li></ul><li>Epidemiology<br /><ul><li>Earthworm transport hosts are important factors in the transmission of Syngamus trachea.
Other invertebrates may also serve as paratenic hosts and these include terrestrial snails and slugs as well as the larvae of Muscadomestica (the common house fly) and Luciliasericata (the green bottle fly responsible for cutaneousmyiasis). </li></li></ul><li>Treatment of Syngamus trachea<br /><ul><li>Ivermectin