The development of nasal avian schistosomes of the genus Trichobilharzia in their final host is poorly known. Therefore,
an experimental infection of ducklings (Anas platyrhynchos f. dom.) by T. regenti was performed. The infection resulted
in leg paralysis and orientation/balance disorders of birds. The examination of the duck's spinal cord and brain confirmed
the presence of developing parasites in pre-patent as well as patent periods. The absence of the worms in other tissues
strongly supports our hypothesis that the parasite migrates through the central nervous system (CNS) to its final location
in bird nasal mucosa. The injury level is probably dependent on number of parasites as well as yet unknown host factors.
The affinity to the CNS seems to be high; also by exposure of experimental animals to low cercarial doses the growing
worms in the CNS were found. In addition to the generally accepted view that bird schistosomes may cause cercarial
dermatitis of mammals (including man), there is evidence of a partial development of T. regenti in mouse CNS; in certain
cases leg paralysis was also recorded. Therefore, the pathogenesis spectrum caused by bird schistosomes in birds/mammals
needs to be reconsidered.