CHAPTER VII 
DISEASES CAUSED BY FUNGI 
General statement. There is a large literature on the relation of 
fungi to disease in man and animals. The number of fungi that grow 
in living animal tissues, however, is not large and those that are thus 
facultatively parasitic are not often encountered. For these reasons, 
the more common morbid conditions produced by them will be briefly 
described without special reference to their classification. 
ASPERGILLOSIS 
Characterization. The term Aspergillosis has been given to the 
morbid changes or diseases in different species of mammals and birds 
caused by the genus Aspergillus. This genus of fungi has been found 
to grow in the tissues of a number of species of animals. The litera- 
ture contains a considerable number of reports of cases of Asper- 
gillosis. ‘The lesions encountered, as a result of the growth of this 
fungus, are largely restricted to the respiratory tract. Cadeac, 
Schneidemihl, Friedberger and Fréhner, Ostertag, Kitt and others 
have called attention to mycotic pneumonia or pneumomycosis. 
Rénon considered the lesions resulting from aspergillus infection as a 
pseudo-tuberculosis which he thought should be designated as Asper- 
gillar tuberculosis. 
The genus Aspergillus belongs to the mucedinz or moles. Al- 
though there are several species in the genus, A. fumigatus is the one 
most commonly found in animal tissues. A. malignus has been 
reported to occur in the ear of man and to be pathogenic for rabbits. 
The infection takes place through ingestion. or inhalation of the 
spores only. It has been observed in tissues other than the lungs and 
it is exceedingly rare for aspergillosis to pass directly from one animal 
to another. Although it is widely distributed on forage it does not 
appear to cause any trouble until some favorable condition enables it 
to multiply in the animal body. It is said to become more virulent 
when passed from one animal to another. In birds infection com- 
monly follows the ingestion of grain charged with spores and the 
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