Cause.—Due to germs. The Bacillus of Black Leg perhaps gains entrance to the blood by wounds of the skin or the mucous membranes lining the mouth and the intestines. This disease principally affects cattle, although sheep and goats may become affected with the same disease.

Symptoms.—This disease affects cattle that are in good condition between the ages of six months and two years. In most cases death is very sudden, and perhaps the animal is found dead. The first symptoms are high temperatures from 104° to 108°F., loss of appetite, the animal stops chewing the cud, breathing considerably hurried, the joints of the limbs become swollen, also the chest and shoulders. All the swellings are painful on pressure and spread very rapidly over the body. The affected animals move with great difficulty and lie down frequently. If the hand is passed over the body, there is a peculiar crackling sound due to the gas developing under the skin. At the most distended portions of the swellings the skin becomes dry and the animal apparently has no sense of feeling. If the skin is punctured at this place, there will be a dark red, frothy discharge which has a very disagreeable odor. There will be a shivering of the muscles and the animal dies in convulsions.

Treatment.—Remove non-affected animals to non-infected pastures, and confine affected animals to as small a territory as possible. The carcasses of the dead animals should be buried deep and covered with lime or burned, being very careful that all blood stains on the ground where the animals have been skinned are thoroughly disinfected. Inoculation is necessary, and is the best form of treatment in localities where Black Leg exists. Inoculate or vaccinate the calves when six months old or over, although after the animal reaches the age of two years or over they generally become immune from this disease.