CHAPTER VI 
DISEASES CAUSED BY HIGHER BACTERIA 
GENUS ACTINOMYCES 
General discussion of the genus. There is considerable confusion 
regarding the genus Actinomyces. The higher bacteria having fila- 
ments showing true branching and that form the so-called rosettes in 
the tissues are placed here in the genus Actinomyces. There seem 
to be good reasons for retaining both the generic and specific name of 
Actinomyces bovis given by Bollinger and Harz to the organism, which 
forms clubs and which causes the lesions in cattle known as actino- 
mycosis. The forms that have filaments with true branching but do 
not form rosettes in the tissue are placed in the genus Nocardia 
(Streptothrix). 
Wright has questioned whether the “actinomyces colony” is an 
essential product of the microérganism itself, that is, a product 
analogous to capsule formation among lower bacteria, or a deposit 
upon the microérganism from the surrounding tissue and fluids. The 
animal fluids seem to be essential for their production. The function 
of the clubs or hyalin envelope surrounding the peripheral filaments 
seemed, according to Wright, to be to protect the mass of the colony 
from the destructive action of the juices and cells of the tissue. 
Bostrcem and others have pointed out that the clubs are formed only 
when there is evidence of resistance on the part of the tissue to the 
organism. In rapidly spreading cases of actinomycosis, it has been 
shown that there is little or no club formation. 
ACTINOMYCOSIS 
Synonyms. Lumpy jaw; wooden tongue; big head. 
Characterization. Actinomycosis is a chronic disease determined 
by the presence of a specific cause—the ray fungus—which by irrita- 
tion stimulates the formation of new growths consisting of round cells, 
epithelioid cells, giant cells and fibrous tissue. The neoplasms appear 
as tumors having either a tendency to develop into large and hard 
masses or to suppurate. Wright restricts the meaning of actinomy- 
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