http://www.jstage.jst.go.jp/article/...1/11/1549/_pdf
Zoonotic Risk for Influenza A (H5N1) Infection in Wild Swan Feathers
(H5N1 in Schwanenfedern)


http://www.ncbi.nlm.nih.gov/pubmed/20484562
Persistence of highly pathogenic avian influenza virus (H7N1) in infected chicken:
feather as a suitable sample for diagnosis

feather pulp was the best sample to detect and isolate HPAIV from infected chicks from 24 hours after inoculation onwards

feather pulp = Federmark ? Federbrei

Der Federmark-Test war die beste Methode um Vogelgrippe zu diagnostizieren
in Hühnern mindestens 24 Stunden nach Infektion.
Besser als Rachen- oder Kloakenabstriche oder Bluttests.