incomplete milking, or milking at irregular intervals; injury to the udder
by stepping on the teat; blows from the horns and pressure caused by lying
on a rough, uneven surface; chilling of the udder by draughts and lying on
frozen ground; and infection of the glandular tissue by _irritating germs_.
The latter cause produces the most serious, and, sometimes, a very
extensive inflammation. This form of inflammation may spread from one cow
to another, causing the milk to be unfit for food, and bringing about the
loss of one or more quarters of the udder.

_The symptoms_ occurring in the different forms of mammitis differ. The
inflammation may involve one or more of the glands, and may affect either
the glandular or the connective tissue. In some cases the gland may appear
congested for a few days before the inflammatory changes occur. The part
becomes hot, swollen, tender and reddened. It may feel doughy or hard. If
the connective tissue is involved (interstitial form), there is apt to be a
high body temperature, the udder may be much larger than normal, is tender
and pits on pressure. Loss of appetite usually accompanies this form of
mammitis. Very little or no milk is secreted. Sometimes, the milk is
greatly changed in appearance, is foul smelling and contains pus. In
congestion of the udder and rupture of the capillary vessels, the milk may
contain blood.

Mild inflammation of the udder responds readily to treatment. The
interstitial form may terminate in abscesses and gangrene. The replacement
of the glandular tissue by fibrous tissue in one or more quarters is not
uncommon. Death seldom occurs.

_The preventive treatment_ consists in avoiding conditions that may favor
or cause an inflammation of the gland. Animals that have highly developed
mammary glands should be fed a light diet just before and following