DISEASES OF HORSES 67 



acute attack, but when the disease is inoculated into a debilitated 

 and impoverished animal it is apt to start in the latent form. In- 

 oculation on the lips or the exterior of the animal is frequently 

 followed by an acute attack, while infection by ingestion of the 

 virus and inoculation by means of the digestive tract is often fol- 

 lowed by the trouble in the chronic latent form. 



The primary lesion in any form is a local point in which 

 occurs a rapid proliferation of the cell elements which make up the 

 animal tissue with formation of new connective tissue, with a crowd- 

 ing together of the elements until their own pressure on each other 

 cuts off the circulation and nutrition, and death takes place in them 

 in the form of ulceration or gangrene. Following this primary 

 lesion we have an extension of infection by means of the spread of 

 the bacilli into those tissues immediately- surrounding the first in- 

 fected spot, which are most suitable for the development of simple 

 inflammatory phenomena or the specific virus. The primary symp- 

 toms are the result of specific reaction at the point of inoculation, 

 but at a later time the virus is carried by means of the blood vessels 

 and lymphatic vessels to other parts of the body and becomes lodged 

 at different places and develops in them; again, when the disease 

 has existed in the latent form in the lungs of the animal and the virus 

 is awakened into action from any cause, we have it carried to vari- 

 ous parts of the body and developing in the most susceptible regions 

 or organs. The points of development are most frequently deter- 

 mined by the activity of the circulation and the effects of exterior 

 irritants. For example, if a horse which has been so slightly 

 affected with the virus of glanders that no symptoms are visible is 

 exposed to cold, rain, or sleet, or by the nibbing of the harness on 

 the body and the irritation of mud on the legs, the disease is apt 

 to develop on the exterior in the form of farcy, while a full-blooded 

 horse which is employed at speed and has its lungs and respiratory 

 tract gorged with blood from the extreme use of these organs will 

 develop glanders as the local manifestation of the disease in the 

 respiratory tract. 



The previous reference to the existence of glanders under the 

 two forms more commonly differentiated as glanders and as farcy, 

 and our reference to the various conditions in whfch it may exist 

 as acute, chronic, and latent, show that the disease may assume sev- 

 eral different phases. Without losing sight for a moment of the 

 fact that all of these varied conditions are identical in their origin 

 and in their essence, for convenience of study glanders may be 

 divided into three classes chronic farcy, chronic glanders, and 

 acute glanders with or without farcy. 



Chronic Farcy Symptoms. In farcy the symptoms com- 

 mence by formation of little nodes on the under surface of the skin, 

 which rapidly infringe on the tissues of the skin itself. These nodes, 

 which are known as farcy buds and farcy buttons, are from the size 

 of a bullet to the size of a walnut. They are hot, sensitive to the 

 touch, at first elastic and afterwards become soft; the tissue is de- 

 stroyed, and infringing on the substance of the skin the disease 



