CHAPTER XXVIII 



THE GROUP OP RAY BACTERIA, LUMPY JAW AND RELATED 

 INFECTIONS— THE GENUS ACTINOMYCES 



Organisms belonging to the genus Actinomyces are very 

 abundant in soil. Many different species have been de- 

 scribed. A few only are known which under certain con- 

 ditions are capable of producing disease in animals and 

 occasionally in man. It is not at all improbable that these 

 are really saprophytic forms which are able to adjust them- 

 selves to parasitic conditions. 



The organisms belonging to this group are intermediate 

 in most of their characteristics between the bacteria and 

 the molds, and by many investigators they are included 

 with the latter. They resemble the molds in producing 

 chains of spores in many cases and also in producing a 

 branched mycelium. In many forms these hyphae may 

 break up into short lengths and function in some eases at 

 least, as spores. Only one species, the form producing 

 lumpy jaw in cattle (Actinomyces bovis) is to be discussed 

 here, although several other species have been described 

 from somewhat similar lesions both in animals and in man. 

 I 

 Actinomyces bovis 



Synon3ans. — Streptothrix bovis, Discomyces hovis. 



This organism and perhaps some closely related species 

 are the specific causes of the disease lumpy jaw and wooden 

 tongue or actinomycosis in cattle and probably in some cases 

 in other animals. The disease lumpy jaw is known from 

 many areas in Europe and North and South America. 



368 



