stomach are the parts which usually form a ventral hernia in
bovine animals.

_Causes._--Hernia is frequently produced by blows of the horns, kicks, and
falls. In old cows hernia may sometimes occur without any direct injury.

HERNIA OF THE RUMEN.--Hernia of the rumen is generally situated on the left
side of the abdomen, on account of the situation of the rumen. In
exceptional cases it may take place on the right side, and in such cases it
also generally happens that some folds of the intestine pass into the
hernial sac. Hernias have been classified into simple or complicated,
recent or old, traumatic (from mechanical injury) or spontaneous.

In recent traumatic hernia there is swelling on the left side of the lower
part of the abdomen. The swelling is greatest in the cases of hernia which
are situated on the lower part of the abdomen. Unless an examination is
made immediately after the injury has been inflicted it is difficult, and
sometimes impossible, to ascertain the exact extent of the rupture, owing
to the swelling which subsequently takes place. Frequently there is no loss
of appetite, fever, or other general symptoms attending the injury. From
the twelfth to the fifteenth day the swelling has generally subsided to
such an extent that it is possible by an examination to determine the
extent of the rupture.

In old cows what is termed spontaneous hernia may sometimes take place
without any direct injury. The occurrence of this form of hernia is
explained by the increase in the size of the abdomen, which takes place in
an advanced stage of pregnancy, causing a thinning and stretching of the
muscular fibers, which at last may rupture, or give way. Such hernias
frequently occur about the end of the period of gestation, and in some
instances have contained the right sac of the rumen, the omentum, the small
and large intestines, a portion of the liver, and the pregnant uterus.

In old hernias the swelling is soft and elastic, and if they have not
contracted adhesions to the sides of the laceration, they can be made to
disappear by pressure carefully applied. Sometimes this accident is
complicated by a rupture of the rumen, constituting a complicated hernia.
If a portion of the contents of the rumen escape into the abdomen, the case
will be aggravated by the occurrence of peritonitis.

HERNIA OF THE BOWEL.--When the intestines (Pl. III, fig. 6) form the
contents of the hernia, it will be situated at the right side