OSTEO-SARCOMA. 195 



CHAPTER Xr. 

 Diseases of the Osseous Structures {continued). 



OSTEOSARCOMA. 



This is a non-inflammatory disease of bone, and is usually 

 defined to be a fibro-plastic degeneration of bone. It is a 

 disease of a malignant character, and is seen oftenest in the 

 finer bred cattle ; and the Duchess strains in particular. 



Causes. — Osteo-sarcoma is supposed to be caused in a 

 great many cases by the attack of a vegetable parasite 

 Avhich is derived from the blue mould seen on leather, old 

 boots, etc., lying in swamps and other damp situations at 

 certain seasons of the year. The parasite causing the 

 disease is known by the name of ' actinomyces,' and another 

 name which has been applied to the disease is ' actinomy- 

 kosis.' The parasite gets into the mucous membrane, 

 possibly in connection with the teeth, and produces the 

 disease. I am satisfied that this parasite produces many 

 conditions that until very recently were supposed to be due 

 to other and entirely different causes. At the present time, 

 however, it cannot be positively stated that osteo-sarcoma 

 is in all instances due to the attack of this parasite. 



Sijmptoms. — The disease occurs oftenest in the lower jaw. 

 A small tumour, very sore and tender, may be observed 

 often in connection with the molar teeth; the teeth generally, 

 after a time, become loose and fall out. Mastication cannot be 

 carried on properly, in consec^uence of which the animal be- 

 comes greatly emaciated and, as a rule, death finally takes 

 place. 



Treatment— O^ieo-^^rcomd, has been looked upon as an 

 incurable disease. However, such a view is a mistaken one, 

 as the disease, if taken in time, can be cured by the proper 

 use of carbolic acid, mercurial preparations, etc. In some 



13—2 



