FISTULOUS WITHERS. 
773 
specific disease in the blood of an animal can, by extravasation 
through the walls of the blood vessels, localize itself in the 
glands or tissues of an organic being and there set up inflamma- ' 
tion from which pus is generated, which in turn destroys the 
texture of these tissues and thus gives rises to a true abscess. 
I am aware that this theory is denied by some pathologists, they 
claiming that the specific germ of a disease is never found in 
any form of pus unless the cavity containing this pus has had 
free access to external air containing the specific germs. 
Symptoms .—The time during which a fistula may exist with¬ 
out exciting the owner’s attention is sometimes quite long. A 
small tumor, often not larger than an orange, may be present 
for several weeks or even months without causing the animal 
any inconvenience other than a slight itchiness of the parts. 
Perhaps at this stage of the disease there is no discharge from 
the enlargement; in the majority of cases but one side of the 
withers is affected, and this is usually the right one. During 
this primary stage of the malady, appearances are quite decep¬ 
tive ; all this time the disease is burrowing down among the 
muscles and tissues and destroying them. In many of these ap¬ 
parently mild cases the dorsal spines will be found to be con¬ 
siderably diseased. The contents of the fistulous sac during this 
early stage (and usually long afterwards when not interfered 
with surgically) is a thin straw-colored fluid in which flakes of 
clotted lymph float free. Where any of the various blistering 
liniments have been applied by the laity to “ scatter the bunch,” 
this fluid is changed into a thick creamy pus when the animal 
is healthy and in good flesh ; it may also be thin and of a sanious 
nature, foul smelling and streaked with blood, when the animal 
is emaciated and in ill-health. I am aware that many authors 
divide the many injuries and diseases found upon the withers 
into several classes, such as oedemas, hsematomas, cysts, ab¬ 
scesses, etc. For my part, I have been unable to make these nice 
distinctions in actual practice, finding that one or the other 
usually ends in a case of fistula. 
Treatment .—The late Dr. D. Hayes Agnew said in regard to 
