Syngamus trachea

Also known as:

Gapeworm Syngamus parvis Syngamus gracilis

S. bronchialis is a nematode of the superfamily strongyloidea, and are found worldwide. It commonly affects the lungs of many game birds within the UK.

Hosts

Chicke, turkey, pigeon and game birds.

Identification

The female is deep red in colour, and the male is white. They are permanently copulating forming a Y shape. The worms have large buccal capsules.

Life Cycle

• The 'gapeworm' - an atypical strongyloid.
• Deep red in colour.
• 'Y'-shaped as the smaller male is permanently attached to the female.
• Lives in the trachea.
• Wide host range, including many wild birds (rooks and crows commonly affected) as well as poultry and game birds.
• Causes respiratory distress (gapes), especially in young birds.

Life-Cycle

• The egg is like a typical strongyle egg, except that there is an operculum at each end.
• Infective larva develops inside the egg.
• Birds can be infected by ingesting:
  • the larvated egg
  • the larva after hatching out of the egg
  • or by eating an earthworm (transport host) that has previously swallowed an egg or larva.

Epidemiology

Gapes is a common and serious problem in pheasant poults. A common sequence of events is as follows:

• Infected wild birds (e.g. crows):

→ droppings on ground

→ soil contaminated with Syngamus eggs

→ earthworms infected

→ reservoir of infection

→ eaten by pheasant poults reared on earth-floored pens in woodland

→ disease.