Common Diseases of Farm Animals

by Robert Alexander Craig

The skin over the under side of the neck, body and inside of the thighs may appear red or purplish-red in color. The different groups of lymphatic glands are enlarged and softened. They may vary in color from a grayish-red to a deep red, depending on the degree of engorgement with blood. The pleura and pericardium may show small red spots and blotches. The kidneys are usually lighter colored than normal, and marked with red spots and blotches (Fig. 81). The spleen may show no evidence of disease. It may be large and soft, or even smaller than normal. The liver may be enlarged and dark, or mottled and light colored.

The stomach and intestines may show hemorrhagic spots and blotches.
Sometimes the gastric and intestinal mucous membrane is a brick red.
Ulceration of the mucous membrane is common (Fig. 83).

[Illustration: FIG. 83.—A piece of intestine from a hog that died of chronic hog-cholera, showing appearance of intestinal ulcers.]

Small, red spots may be present on the surface of the lungs (Fig. 82). Scattered lung lobules or a large portion of the lungs may be inflamed. In chronic hog-cholera, pleural exudation, adhesions and abscesses in the lung tissue may occur. Inflammations of the pericardium and heart muscle are less common lesions.

PREVENTIVE MEASURES.—Hog-cholera is the most widespread infectious disease of hogs, and all possible precautions against its distribution to healthy herds should be practised. Hogs coming from other herds and stock shows should be excluded from the home herd until they are positively shown to be free from disease. They should be quarantined in yards set off for this purpose. The hogs should be cleaned by dipping or washing them with a disinfectant. The quarantine period should be longer than the average period of incubation. Three weeks is sufficient.

The possible introduction of the disease into the pens by people, dogs, birds and other carriers of the disease should be guarded against, especially if cholera is present in the neighborhood. The exchange of help at threshing and shredding time with a neighbor who has hog-cholera on his farm is a common method of distributing the infection. It is not advisable to allow a stranger to enter your hog-houses and yards, unless his shoes are first disinfected. Whenever it is necessary for a person to enter yards where the disease is present, the shoes should be cleaned and disinfected on leaving. The wheels of wagons, and the feet of horses that are driven through cholera yards, should be washed with a disinfectant. The feet of feeding cattle that are shipped from stock-yards should be treated in the same manner. Persons taking care of cholera hogs should observe the necessary precautions against the distribution of the disease, and see that others practise like precautions.

Hog-yards should be well drained and all wallow holes filled. Pens and pastures through which the drainage from the swine enclosures higher up flows should not be used for hogs.

CARE OF A DISEASED HERD.—When an outbreak of hog-cholera occurs on a farm the farm should be quarantined. The herd should be moved away from running streams, public roads and line fences, so that neighboring herds are not unnecessarily exposed to the disease. During the hot weather shade and an opportunity to range over a grass lot or pasture are highly necessary. A recently mowed meadow, or a blue grass pasture and a low shed, open on all sides and amply large for the herd to lie under, give the animals clean range and comfortable, cool quarters. Roomy, dry, well-ventilated sleeping-quarters that are free from drafts and can be cleaned and disinfected are best when the weather is cold and wet.

In the subacute, and in the early part of an acute outbreak of hog-cholera, it is advisable to separate the sick from the well hogs. The fatally sick animals should be destroyed.

[Illustration: FIG. 84.—Cleaning up a hog lot.]