Common Diseases of Farm Animals

by Robert Alexander Craig

Abrasions and superficial wounds usually heal under a scab. The scab is formed by the blood and wound secretions. This protects the surface of the wound until finally the destroyed tissue is replaced by the granulations, and the skin surface is restored.

Abnormal granulation is not an uncommon form of healing in domestic animals. Mechanical and bacterial irritation causes the injured tissue to become swollen and inflamed. In such a wound, excessive and rapid granulation occurs, the new tissue piling up over the cut surfaces and appearing red and uneven. This is termed excessive granulation or "proud flesh." This tissue may refuse to "heal over," or the scar may be large, prominent and painful. Abnormal tissue (horny or tumor-like) may sometimes form.

WOUND TREATMENT.—Wounds in domestic animals are frequently allowed to heal without special care or treatment. This is unfortunate. The careful and intelligent treatment of wounds would greatly decrease the loss resulting from this class of injuries. The method of treatment varies in the different kinds of wounds.

The first step in the treatment is to check the haemorrhage. Heat, ligation, pressure and torsion are the different methods recommended. Bathing the wound with hot water (115\260-120\260 F.) is a satisfactory method of controlling haemorrhage from small blood-vessels. Ligation and torsion of the cut end of large blood-vessels should be practised. Pressure over the surface of the wound is the most convenient method of Controlling haemorrhage in most cases. Whenever possible, the part should be bandaged heavily with clean cheese cloth or muslin. Before applying the bandage, it is advisable to cover the wound with a piece of sterile absorbent cotton that is well dusted with boric acid. Hemorrhage from wounds that cannot be bandaged may be temporarily stopped by pressure with the hand, or, better, by packing the wound with absorbent cotton and holding this in place with sutures. This should be left in place for a period of twelve or thirty-six hours, depending on the extent of the haemorrhage and character of the wound.

The next step is the preparation of the wound for healing. The injured tissues should be carefully examined for foreign bodies such as hair, dirt, gravel, slivers of wood and nails. The hair along the margins of the wound should be trimmed, and all tissue that is so torn and detached as to interfere with healing cut away. Drainage for the wound secretions and pus should be provided. The advisability of suturing the wound depends on its character and location. A contused-lacerated wound should not be closed with sutures unless it is clean and shows no evidence of sloughing. A badly infected wound should be left open unless satisfactory drainage for the pus and wound secretions can be provided. Wounds across the muscle and in parts that are quite movable should not be sutured.

The after-treatment consists in keeping the animal quiet, if the wound is in a part that is quite movable, and preventing it from biting, licking or nibbling the injury. Wounds in the region of the foot become irritated with dirt and by rubbing against weeds and grass. This makes it advisable to keep the animal in a clean stall until healing is well advanced. Local treatment consists in keeping the wound clean by washing the part daily, or twice daily, with a one per cent water solution of a cresol disinfectant. Liquor cresolis compositus may be used. It is sometimes advisable to protect the granulating surface against irritation by dusting it over with a non-irritating antiseptic powder, or applying a mixture of carbolic acid one part and glycerine twelve parts. After the wound shows healthy granulations longer intervals should lapse between treatments.

In poorly cared for, and badly infected wounds, the part may become badly swollen, the granulations pile up and the wound refuse to "heal over." It may be advisable in such cases to cut away the excessive granulations and stop the haemorrhage by cauterization with a red-hot iron, or by compression. Unhealthy granulations may be kept down by applying caustic occasionally.

ABSCESS.—This is an accumulation of pus in the tissues. It may be due to a severe bruise or contusion that is followed by the infection of the part with some of the pus-producing bacteria. Abscesses occur in certain infectious diseases. In strangles, the disease-producing organism may be carried to different regions of the body by the circulatory vessels. This may result in a number of abscesses forming in the different body tissues.

The following forms of abscess are recognized: hot and cold, superficial and deep, simple and multiple. The hot is the acute, and the cold the chronic abscess. The terms superficial and deep allude to the relative position of the abscess, and simple and multiple to the number present.

An abscess may first appear as a hot, painful swelling. If superficial, the skin feels tense and the contents fluctuate when pressed on. Later the fever subsides and no pain may occur when the abscess is pressed upon. Deep abscess may not fluctuate.