mild cases or a chalky whiteness
in more severe affection. Cases of ulceration of the cornea followed by
perforation and subsequent escape of the aqueous humor, leading to
shrinking of the eyeball and permanent loss of sight, have been recorded,
but these are relatively rare, although slight inflammation of the deeper
structures of the eye (iris) are more frequent. In mild cases this
inflammation may undergo complete resolution, but more frequently permanent
cloudliness of the cornea, either diffuse or in spots (leucoma), is the
result. The mucous membrane of the mouth, nose, sinuses of the head,
throat, and lower respiratory passages are also involved. It is first
catarrhal in character, but soon a false or diphtheritic membrane is
formed, with the production of shallow ulcers. There is dribbling of saliva
from the mouth and discharge from the nose, at first watery, becoming
thicker and mixed with blood and small masses of cast-off croupous
membrane, causing a very fetid odor. These croupous areas when they form in
the throat, larynx, or windpipe, may lead to narrowing of the passages,
with consequent difficult breathing and even suffocation. Various
respiratory murmurs may also be heard, caused by the to-and-fro movement of
mucus and inflammatory deposits along the air passages. There is also
inflammation of the horn core with consequent loosening of the horn shell,
and the horns are thus readily knocked off by the uneasy, blind sufferer.
The animal may refuse all feed from the time of the initial rise of
temperature, or in less severe cases, and especially when the lesions of
the digestive tract are not so marked, the appetite may remain until the
disease is well advanced. Constipation is quite common at the commencement
of the attack, followed by diarrhea and severe straining, the evacuations
becoming very soft, fetid, and streaked with blood. Cases of the evacuation
of desquamated patches of diphtheritic membrane from the intestinal mucosa
6 to 9 feet in length have been reported. The kidneys and bladder are
usually inflamed, the urine being voided with difficulty and the animal
evincing signs of pain. Inflammatory elements, as albumen, casts, etc., may
be seen on examination of the urine. In cows the mucous membrane of the
vestibule is congested, swollen, and may contain ulcers and an excessive
quantity of mucus. Abortion during advanced pregnancy is not infrequent,
following a severe attack. In connection with thes
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