Hernia of the rennet, or fourth stomach.—This disease occasionally occurs in calves and is usually caused by a blow from a cow's horn on the right flank of the calf. After such an accident a swelling forms on the right flank near the last rib. This swelling may be neither hot nor painful, even at first, and is soft to the touch. It can be made to disappear by careful pressure, when the sides of the aperture through which it has passed can be felt. The application of pressure so as to cause the disappearance of the hernia is best made immediately after the occurrence of the accident, or when the edema which accompanies the swelling has disappeared.
Treatment.—When a hernia is reducible—that is, can be pushed back into the abdomen—then, if it is of recent occurrence, it is advisable to maintain the natural position of the parts by bandaging and to allow the walls of the laceration to grow together. The bowels should be kept reasonably empty by avoiding the use of bulky feed, and the animal must be kept quiet.
The following method of bandaging is recommended by Bouley:
First prepare a bandage (must be of strong material), about 10 yards long and between 3 and 4 inches broad, and a flexible and solid piece of pasteboard adapted in size to the surface of the hernia. The protruding organ must then be replaced in the abdomen and maintained in that position during the application of the bandage. This being done, a layer of melted pitch and turpentine is quickly spread on the skin covering the seat of the hernia, so as to extend somewhat beyond that space. This adhesive layer is then covered with a layer of fine tow, then a new layer of pitch and turpentine is spread on the tow, and the piece of pasteboard is applied on the layer of pitch, its outer surface being covered with the same preparation. Lastly, the bandage, adhering to the piece of pasteboard, to the skin, and to the different turns which it makes around the body, is carefully applied so as to form an immovable, rigid, and solid bandage, which will retain the hernia long enough for the wound in the abdominal walls to heal permanently.
If the hernia is old and small it may be treated by injecting a strong solution of common salt about the edges of the tear. This causes swelling and inflammation, which, respectively, forces the protruded organ back and closes the opening. There is some risk attached to this method of treatment.
In small, old, ventral hernias the method of compressing and sloughing off the skin has been used successfully. If the hernia is large a radical operation will be necessary, and this is also true when the symptoms indicate that a hernia is strangulated. This operation is performed by cutting down on the hernia, restoring the organ to the abdominal cavity, and then closing the wound with two sets of stitches; the inner stitches, in the muscular wall, should be made with catgut and the outer stitches, in the skin, may be made with silk or silver wire. The strictest surgical cleanliness must be observed. Bleeding vessels should be tied. Then a compress composed of ten or twelve folds of cloth must be placed smoothly over the seat of injury and a bandage applied around the body, the two ends being fastened at the back. In the smaller kinds of hernia, nitric acid may sometimes be applied with success. This treatment should not be applied until the swelling and inflammation attending the appearance of the hernia have subsided; then, the contents of the hernia having been returned, the surface of skin corresponding to it is sponged over with a solution composed of 1 part of nitric acid to 2 of water. This treatment acts by exciting considerable inflammation, which has the effect of causing swelling, and thus frequently closing the hernial opening and preventing the contents of the sac from returning. A second application should not be made until the inflammation excited by the first has subsided. In what is termed spontaneous hernia it is useless to apply any kind of treatment.
Umbilical hernia.—The umbilicus, or navel, is the aperture through which the blood vessels pass from the mother to the fetus, and naturally the sides of this aperture ought to adhere or unite after birth. In very young animals, and sometimes in newborn calves, this aperture in the abdominal muscles remains open and a part of the bowel or a portion of the mesentery may slip through the opening, constituting what is called umbilical hernia. The wall of the sac is formed by the skin, which is covered on the inner surface by a layer of cellular tissue, and within this there is sometimes, but not always, a layer of peritoneum. The contents of the hernia may be formed by a part of the bowel, by a portion of the peritoneum, or may contain portions of both peritoneum and bowel. When the sac contains only the peritoneum it has a doughy feel, but when it is formed by a portion of the bowel it is more elastic on pressure.
Causes.—In the new-born animal the opening of the navel is generally large, and may sometimes give way to the pressure of the bowel on account of the weak and relaxed condition of the abdominal muscles. This defective and abnormal condition of the umbilicus is frequently hereditary. It may be occasioned by roughly pulling away the umbilical cord; through kicks or blows on the belly; through any severe straining by which the sides of the navel are stretched apart. We may mention in this connection that it is best in new-born calves to tie the umbilical cord tightly about 2 inches from the navel, and then to leave it alone, when in most cases it will drop off in a few days, leaving the navel closed.
Treatment.—It is well to bear in mind that many, and especially the smaller, umbilical hernias heal spontaneously; that is, nature effects a cure. As the animal gets older the abdominal muscles get stronger and possess more power of resistance to pressure, the bowels become larger and do not pass so readily through a small opening, so that from a combination of causes there is a gradual growing together or adhesion of the sides of the navel. In cases of umbilical hernia in which there are no indications that a spontaneous cure will take place, the calf should be laid on its back; immediately on this being done the hernia will often disappear into the abdomen. If it does not, its reduction may be brought about by gentle handling, endeavoring, if need be, to empty the organs forming the hernia before returning them into the abdomen. After the hernia has been returned, the hair should be clipped from the skin covering it and a compress composed of 10 or 12 folds of linen or cotton should be applied, first smearing the skin with pitch and then a bandage about 3 inches wide should be passed round the body so as to retain the compress in position. The lower part of the compress should be smeared with pitch, and also those portions of the bandage which pass over it, so as to keep it solid and prevent it from shifting. In some cases it will be found that the contents of the sac can not be returned into the abdomen, and this generally arises from the fact that some part of the contents of the sac has grown to or become adherent to the edges of the umbilical opening. In such a case the skin must be carefully laid open in the long direction, the adhesions of the protruding organs carefully separated from the umbilicus, and after the protruding parts have been returned into the abdomen, the sides of the umbilicus must be freshened if necessary by paring, and then the edges of the opening brought together by catgut stitches; the wound in the skin must then also be brought together by stitches. The wound must be carefully dressed every day and a bandage passed round the body so as to cover and protect the part operated on.
In small hernias nitric acid has been used successfully in the same manner as has been described in the treatment of ventral hernia. Sulphuric acid has also been used for a similar purpose, diluting it to the extent of 1 part of acid to 3 or 5 of water. In thin-skinned animals the weaker preparations ought to be preferred, and caution must be exercised in using such preparations so as not to destroy the tissues on which they are applied.