PRINCIPLES OF VETERINARY SURGERY 497 



recent lesions and at a time when it was still in the filament- 

 ous form. Liebmann has demonstrated that the pathogeni- 

 city of the parasite emanating from an actinomycostic fistula 

 can only be restored by passing it through a plant cultiva- 

 tion. 



Therefore the instances of enzootic outbreaks must not 

 be regarded as the result of contagion. Actinomycosis is no 

 more contagious than anthrax, for example : the cause of 

 outbreaks in a large number of animals in one region, or on 

 the same farm, is the ingestion of the same food. 



These considerations demonstrate that the danger of in- 

 fection from meat of actinomycostic animals is nil. The para- 

 site in meat is already almost deprived of its pathogenicity, 

 and cooking, even though slight, removes all grounds for 

 apprehension. It is therefore absolutely illogical to attribute 

 The cases of intestinal actinomycpsis to the ingestion of meat 

 taken from infected animals. 



Is the actinomyces pyogenic? This question seems per- 

 fectly useless since the parasite discloses its presence in the 

 tissues by suppuration. This point is, however, disputed. 

 Netter holds that the parasite is clearly pyogenic, while oth- 

 ers hold that the pyogenic power is the work of parasitic 

 bacteria of the fungus. In fact, cases of mixed infection 

 have been pointed. The investigations of Israel, Babes, Got- 

 totein, and Roussel demonstrate the constant association of 

 parasites with dififerent microbian forms. The part assigned 

 to these different agents in pyogenesis is still undecided. 

 Some writers are inclined to believe that the cases of spon- 

 taneous recovery are due to a vital combat between the bac- 

 teria and the fungi. 



PATHOGENESIS.— How does the parasite behave in 

 the tissues? Its penetration provokes an organic reaction 

 which ends in fhe construction of a nodule called an 

 actinomycoma, which in its histological constitution resem- 



