Table of Lectures - Society for Mycotoxin Research

L-16 29 th Mycotoxin Workshop
Occurrence of mycotoxins in falcon tissues infected with
Aspergillus fumigatus
K. Meyer1 , J. Lipovsky1 , J. Schulz2 , J. Bauer1 1
TU München, Lehrstuhl für Tierhygiene, Weihenstephaner Berg 3, D-85354 Freising, Germany
2 TiHo Hannover, Institut für Tierhygiene, Tierschutz und Nutztierethologie,
Bünteweg 17p, D-30559 Hannover, Germany
The imperfect fungi Aspergillus fumigatus commonly existing autochthonal as a saprophyte is also
known as an opportunistic pathogen causing severe diseases such as pulmonary invasive aspergillosis,
leading to rising mortality rates in livestock and high economic losses in animal production. Especially
birds are susceptible to infections with the fungus due to their anatomic particularities in the respiratory
tract. For the small conidiospores of A. fumigatus (2 – 3 µm in diameter) the deeper airways are easy
to reach and body temperature of birds enables a fast fungal growth. Once colonised the lung tissue
A. fumigatus dispose of a wide range of virulence factors and toxic or immunosuppressive secondary
metabolites. Beside the antibiotic and angiogenesis inhibiting Fumagillin this are especially the toxins of
the fumitremorgin-verruculogen-group or the highly cytotoxic gliotoxin.
Tissue samples of ten falcons perished in a falcon breeding centre in northern Germany were taken
for pathological, microbiological and mycotoxicological examinations. The samples showed marked necrotic
nodular in lung tissues and in some respiratory airways pronounced hyphea formation and even
sporulations were found. The air sacs were lined with a fungal sward and some airways were clogged
with fungal mycelium. For mycotoxin analysis, kidney, liver, and lung of the birds were examined. The
investigations have been performed by LC-MS-MS. Beside Gliotoxin other neuro- and cytotoxic secondary
metabolites of Aspergillus fumigatus like Verruculogen, TR 2-toxin, Fumitremorgin B and C as well
as Fumagillin have been detected. Concentrations were highest for Gliotoxin (up to 3 µg/g), but those
of Verruculogen and Fumitremorgin C also exceeded the concentrations known to produce neurotoxic
effects. To our knowledge this is the first time that toxins of the Fumitremorgin-Verruculogen-group were
isolated from naturally infected avian tissues.
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