Cause.—The bacilli of Tuberculosis thrive in animals, especially those in a weakened condition, or when exposed to atmospheric changes, unwholesome food, dark and poorly ventilated stables. They gain entrance into the body through the lungs or the intestinal canal. They lodge in various portions of the lungs or intestines, and multiply very rapidly, causing irritations and formations, nodules, cysts or abcesses. They are the means of the bacillus entering the blood, which carries the infection to other parts of the body, as the spleen, liver, udder, womb, etc. Cows affected with generalized tuberculosis, that is to say the infection being confined to not only a small portion of the lungs, but also to any of the above mentioned organs, etc., may give birth to a calf having general tuberculosis at birth, or shortly after, due to the cow’s blood circulating through the body of the calf before birth.

Symptoms.—This disease may pass a casual observer unnoticed, although in some instances we notice a slight cough, unthriftiness, dullness. The coughing is best marked after taking a drink of water in the morning and then being exercised. Some animals keep up in good condition and look perfectly healthy while some get emaciated, have constipation, variable appetite, and sometimes growths or abcesses can be felt or seen in the udder or glands of the body and neck.

However, cattle showing any weakness, or the above symptoms should be tested for tuberculosis by the administration of tuberculin.

Treatment.—It is not advisable to treat tuberculosis. Thus far, medicine has failed to relieve the affected animal, or kill the bacillus of tuberculosis in a living animal. The infected animals should be disposed of on account of tubercular cows giving birth to tubercular calves, the milk being unfit for human consumption, unless it is thoroughly pasteurized. Infected cattle should be separated from healthy ones, as the disease spreads very rapidly. Drinking and feeding troughs are a means of spreading the infection, therefore, suspected cases of tuberculosis should be tested and if the animals react, they should be slaughtered, and if the disease is localized, passed for human consumption. The meat of animals suspected of having tuberculosis, or reacting from tuberculin test, should be well cooked.