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448 DISEASES OF THE HORSE. 
calling it laminitis. The seat of greatest congestion will always 
be found in the neighborhood of the toe, because of the increased 
vascularity of that part, and, although at times it is limited to the. 
podophyllous tissue alone, any or all parts of the keratogenous 
membrane may be affected by the congestion and followed finally 
by inflammation. 
-leute—In the acute form of laminitis the symptoms may all de- 
velop rapidly, or it may commence by the appearance of a little 
soreness of the feet which in 24 or 48 hours develops into a well- 
marked case. This peculiarity of development is due to one of two 
causes. Either the congestion is general, but takes place slowly, 
or it begins in one or more points and gradually spreads through- 
out the lamine. These acute cases generally run their course in 
from one to two weeks. Usually a culmination of the symptoms 
is reached, if the patient is properly treated, in from three to five 
days; then evidences of recovery are discernible in favorable cases. 
The lameness improves, the other symptoms gradually subside, and 
eventually health is regained. It is in these cases that a strong 
tendency to disorganization of a destructive character exists; hence it 
is we see so many recover imperfectly, with maixed structural 
changes permanently remaining. 
Subacute.—Subacute laminitis is most often seen as a termination 
of the acute form, although it may exist independent of or precede 
an acute attack. It is characterized by the mildness of its symptoms, 
slow course, and moderate tissue changes. It may be present a long 
time before any pathological lesions result other than those found in 
the acute form, and when these changes do take place they should 
be viewed rather as complications. 
Chronic-—Chronic laminitis is a term used by many to designate 
any of the sequele of the acute and subacute forms of this disease. 
Pure, chronic inflammation of the lamine is not very commonly met 
with, but is most frequent in horses that have long done fast track 
work. They have “ fever in the feet” at all times and are continually 
sore, both conditions being aggravated by work. Like chronic in- 
flammation of other parts, there is a strong tendency to the develop- 
ment of new connective tissue which, by its pressure upon the blood 
vessels, interferes with nutrition. Wasting of the coffin bone and 
inflammation of its covering with caries is not unusual. The con- 
tinued fever and impaired function of secretion result in the produc- 
tion of a horn deficient in elasticity, somewhat spongy in character, 
and inclined to crumble. In some cases of “soreness” in horses used 
to hard or fast work there is evident weakness of the coats of the 
vessels, brought on by repeated functional exhaustion. Here slight 
work brings on congestion, which results in serous effusion and 
temporary symptoms similar to those of chronic laminitis. 
