ACTINOMYCOSIS. 125 



Aotinomycosis. 



This is a disease caused by the ray-fungus (actinomyees). 

 " According to Brazzola, it grows principally on Hordeuvi 

 marinum (a kind of barley). Upon the fragments of this grain 

 which had penetrated into the gum, he has found a mass of 

 actinomyees among the vegetable fibres. Johne and Piana have 

 met with this fungus on the husks of wheat fixed in the tonsils 

 and in the tongue of an ox " {Friedherger and Frbhner). It seems 

 probable that it gains entrance into the system only through a 

 wound. In the vast majority of cases it is confined to cattle. 

 It is found in men,' seldom in pigs and very rarely in horses. 

 Blanchard states that carnivorous animals do not take it, even by 

 inoculation. Vachetta, however, reports a case of it in the dog. 

 Hammond has seen it in a sheep. In cattle, men, and horses, it 

 is essentially a disease, at first, of the skin and mucous membranes, 

 from which it extends to the underlying tissues. In cattle, the 

 tumours are known as wens, clyers, crewels, sitfasts, polypus, 

 cancer of the tongue, cancer of the jaw, spina-ventosa, osteo- 

 sarcoma, etc. (Orookshank). It has frequently been mistaken for 

 tuberculosis. Liebman has shown that this fungus, if inoculated 

 in a grain of corn, will grow according as the grain becomes 

 developed, and will invade the whole of the plant. He also points 

 out that the fungus, by residence in the animal body, loses to 

 a certain extent its contagious power ; but regains it when it 

 becomes transferred to a vegetable host. This fact may account 

 for the rarity of the disease among dogs and other carnivorous 

 animals. There is very little evidence to prove that in ordinary 

 course, it has ever been transmitted from one animal (including 

 man) to another. Its usual point of entrance is no doubt by the 

 mouth and with the fodder. It may be carried into the lungs 

 along with dust. In cattle it not infrequently forms a malignant 

 tumour in the jaw by gaining entrance by means of a wound 

 on the gum, or through a decayed tooth. Nocard points out 

 that the geographical distribution of this fungus is very erratic; 

 it being frequent (among cattle) in some countries and districts, 

 and absent in others. It is very rare in France ; but is often met 

 with in Holland, Eussia, Scotland and the United States. 



The only cases of actinomycosis I have read of in the horse are : 

 one in the skin and underlying tissues of the thigh, subsequent to 

 a wound, reported by Perroncito; and instances in the tongue, 

 described- respectively by Zschokke, Truelsen, Israel, Baracz, and 

 Gtuber. 



