Over-driving and hurrying of every kind, is, in my opinion, a fruitful source of rot, not only from the fatigue it causes, or the risk it leads to of taking cold, but also from the injury, which in many cases results, to the delicate texture of the lungs. As shown in the note to paragraph (157), no animal is more easily put out of breath by running, than the sheep. Whenever the breathing is hurried, the circulation through the lungs is quickened also. If the tissue of the lungs be in any way delicate, the force with which the blood is propelled is sure to make it yield, and in this manner the animal is often suffocated by the large quantity of blood, which issues into the air tubes at once from many points. Fig. 1, Plate VI. exhibits a good illustration of this taken from a sheep. Numerous red points are seen sprinkled over the surface of the section, indicating that blood has been effused from many minute torn vessels. Now, if this animal had survived, each speck of blood would have formed a centre, round which tuberculous matter, as in Fig. 2, Plate VI. would have been secreted, and death from rot, at some ulterior period, would, in all probability, have been the result.[40]
[40] Pathologists differ as to whether tubercle is the cause or consequence of _hemoptysis_, as this effusion of blood into the tissue of the lungs is termed. Andral, however, is decidedly of opinion that hemoptysis is one of the exciting causes, and, in domestic animals, I believe it to precede tubercle more frequently than is generally imagined.
(165.) _Treatment of Rot._ As reason and experience have taught us that tathy herbage is a common cause of this complaint, we should, when it shows itself, at once remove the animals to a better pasture, where they should be exempted from teazing of every kind.
Salt appears, after every trial, to be the best medicine, and to this they should have, at all times, ready access. Should the disease be rather far advanced, the breathing hurried, and the cough annoying, occasional doses of the following infusion will be of service, in enabling the farmer to keep down the disease, till such time as he can conveniently dispose of the animal.
Take of Leaves of Foxglove two ounces, Boiling water two English pints: