the
adjacent tissue, where it clots, and the wound, remaining open in the
artery, causes pulsation in the tumor.

THROMBOSIS (OBSTRUCTION) OF THE ARTERIES.

Arteries become obstructed as a result of wounds and other injuries to
them, as those caused by the formation of an abscess or the extension of
inflammation from surrounding structures to the coats of an artery.
Arteries are also obstructed by the breaking off of particles of a plug or
clot, partly obstructing the aorta or other large artery. These small
pieces (emboli) are floated to an artery that is too small to permit them
to pass and are there securely held, producing obstruction. These
obstructions are shown by loss of power in the muscles supplied by the
obstructed artery and by excitation of the heart and by respiration after
exercise. The loss of power may not come into evidence until after
exercise.

_Symptoms._--While standing still or when walking slowly the animal may
appear to be normal, but after more active exercise a group of muscles, a
leg, or both hind legs, may be handled with difficulty, causing lameness,
and later there is practically a local paralysis. These symptoms disappear
with rest. In some cases the collateral circulation develops in time, so
that the parts receive sufficient blood and the symptoms disappear.

INFLAMMATION OF VEINS (PHLEBITIS).

When bleeding is performed without proper care or with an unclean lancet,
inflammation of the vein may result, or it may be caused by the animal
rubbing the wound against some object. When inflammation follows the
operation, the coats of the vein become so much enlarged that the vessel
may be felt hard and knotted beneath the skin, and pressure produces pain.
A thin, watery discharge, tinged with blood, issues from the wound. The
blood becomes coagulated in the vessel. In inflammation of the jugular the
coagulation extends from the wound upward to the first large branch.
Abscesses may form along the course of the vein. The inflammation is
followed by obliteration of that part in which coagulation exists. This is
of small import, as cattle have an accessory jugular vein which gradually
enlarges and accommodates itself to the increased quantity of blood it must
carry.

_Treatment._--The treatment for inflammation of the vein is to clip the
hair from along the course of the affected vessel and apply a blister, the
cerate of cantharides. Abscesses should be opened as soon as they form,
be