260 ACTINOMYCOSIS 
Symptoms. Actinomycosis is manifested by a firm swelling or 
tumor usually situated in the region of the head or throat. _ It is first 
recognized as a slight swelling of the affected part resembling some- 
what the result of a bruise. It is stated that many cases of actinomy- 
cosis seem to be caused by blows or injuries received while struggling 
in stanchions. The enlargement gradually increases in size. It is 
ordinarily sharply defined from the surrounding tissues. 
Upon manipulation the tumor feels hard and dense. After a 
variable length of time, the tumor-like mass may soften in one or 
more places, rupture and discharge a rather thick, yellowish and more 
or less sticky, purulent substance. The discharge may continue or, 
as often happens, the opening heals temporarily only to rupture again. 
The discharge often takes place into the cavity of the mouth or throat. 
Sometimes the neoplastic tissue increases in amount until it gradually 
forces its way through the opening, resembling somewhat a cauli- 
flower in appearance. The actinomycotic growth frequently increases 
rapidly in size after it has discharged. In later stages the teeth may 
become ulcerated and loose. 
When the tongue is affected the animal finds it difficult to eat. 
The organ is swollen and in advanced cases hangs from the mouth. 
There is, in these cases, profuse salivation. When the pharynx is 
affected there is difficulty in swallowing and when the larynx is 
attacked there is difficulty in breathing. In this country the tumor 
is most frequently seen on the external surface of the jaw. It is 
stated by Salmon that it usually begins in the connective tissue 
beneath the skin but soon extends to the bone, which it penetrates. 
Actinomycosis of the cervical vertebre may cause spinal paralysis. 
When the lungs are attacked the animal may present the appearance 
of one suffering from a chronic pulmonary disease such as tubercu- 
losis. There are no symptoms characteristic of pulmonary actinomy- 
cosis. 
Actinomycosis is not a rapidly fatal disease. Animals rarely if 
ever die from its immediate effects. The length of time during which 
they survive depends very largely upon the location of the tumor and 
the rapidity of its development. If it is situated where it does not 
interfere seriously with prehension, mastication or swallowing of food 
or where it does not occlude or press upon the respiratory passages the 
animal usually survives for several years. When death occurs it is 
usually due to inanition, the animal being unable to take sufficient 
food, although the drain upon the system by the long continued dis- 
