DISEASES OF CATTLE 291 



partial suffocation. Actinomycosis of the tongue, in interfering with 

 the many and varied movements of this important organ, is also a 

 serious matter. There is no reason to suppose that the localized dis- 

 ease interferes with the general health in any other way than in- 

 directly until internal organs, such as the lungs, become involved. 



A very small proportion of the cases may recover spontaneously, 

 the tumors being encysted or undergoing calcification. In most 

 cases the disease yields readily to proper treatment, and about 75 

 per cent of the affected animals may be cured. 



Prevention. The question as to how and where animals take 

 this disease is one concerning which we are still in the stage of con- 

 jecture, because we possess as yet very little information concerning 

 the life history of the actinomyces itself. The quite unanimous view 

 of all observers is that animals become infected from the food. The 

 fungus is lodged upon the plants and in some way enters the tissues 

 of the head, the lungs, and the digestive tract, where it sets up its 

 peculiar activity. It is likewise generally believed that the fungus 

 is, as it were, inoculated into the affected part. This inoculation is 

 performed by the sharp and pointed parts of plants which penetrate 

 the mucous membrane and carry, with them the fungus. The dis- 

 ease is therefore inoculable rather than contagious. The mere pres- 

 ence of the diseased animal will not give rise to disease in healthy 

 animals unless the actinomyces grains pass directly from the diseased 

 into some wound or abrasion of the healthy or else drop upon the 

 food which is consumed by the healthy. Not only are these views de- 

 ducible from clinical observation, but they have been proved by the 

 positive inoculation of calves and smaller animals with actinomyces. 

 The danger, therefore, of the presence of actinomyces for healthy 

 animals is a limited one. Nevertheless an animal affected with this 

 disease should not be allowed to go at large or run with other animals. 

 If the fungus is being scattered oy discharging growths we certainly 

 can not state at this stage of our knowledge that other animals may 

 not be infected by such distribution, and we must assume, until more 

 positive information is at hand, that this actually occurs. 



It is, however, the opinion of the majority of authorities that 

 when actinomycosis appears among a large number of animals they 

 all contract it in the same way from the food. Much speculation has 

 therefore arisen whether any particular plant or group of plants is 

 the source of the infection and whether any special condition of the 

 soil favors it. Very little positive information is at hand on these 

 questions. It would be very desirable for those who live in localities 

 where this disease is prevalent to make statistical and other observa- 

 tions on the occurrence of the disease with reference to the season of 

 the year, the kind of food, the nature of the soil (whether swampy or 

 dry, recently reclaimed or cultivated for a long time) upon which the 

 animals are pastured or upon which the food is grown. 



It is highly probable that such investigations will lead to an un- 

 derstanding of the source of the fungus and the means of checking 

 the spread of the disease itself. Veterinarian Jensen, of Denmark, 

 made some observations upon an extensive outbreak of actinomycosis 



