Filaroides osleri

F. osleri is atypical of the Metastrongyloidea in almost every way.
Adults (approximately 1cm) are found in dogs clustered in fibrous nodules (few mm - 2cm) on tracheal wall (near bifurcation of trachea).
This means that small numbers of L1 are found in the sputum, and can either be passed to the skin during grooming, or can be passed in the faeces (dead-end for life-cycle).
Transmission from bitch to pups occurs during grooming via transfer of sputum.
Horizontal transmission rarely, if ever, happens.
Infection is usually asymptomatic, but if symptoms are present, there is a chronic, dry, debilitating cough - performance of greyhounds may be affected.