It is to be understood that the membrana tympanl, or drum membrane of the ear, is the division between the so-called external and middle ear. In treating of the affection which we were obliged to call canker, owing to the difficulty and inconvenience of displacing it, inflammations of the external ear were alone considered. There remains affections of the tympanum and internal ear to be described.

Otitis is strictly the proper name to apply to inflammations of the ear in general; to this may be added terms to distinctly designate the particular locality and structure affected.

In a general way the ear may be divided thus: external, middle or internal. Still other subdivisions might be made, but they are needless in this work and would simply tend to confuse the reader. The middle ear is the space internal to the drum membrane, and the internal ear is beyond that and comprises the deeper structures. Properly inflammations of the ear should be denominated thus: otitis externa, media or interna.

As the first has already been considered as canker, there now remains to be described otitis, media or interna. In this disease the cavity of the ear becomes inflamed, involving the drum and generally the external ear, and invading the cells and inner structures. The inflammation may be confined to the mucous membrane alone, or with it the membrane covering the bone and even the bone itself may become affected.

Causation

The usual causes are exposure to cold, sudden chills such as may result from plunging into the water and remaining too long, violent injuries and blows in the region of the ear, and foreign bodies in the external passage. Powerful chemical liquids which have been poured into the ear, accidentally or for the purpose of treatment, may so irritate the drum that deep seated inflammation will result.

The disease may have its origin in the middle ear or it may follow the profuse purulent discharge of a severe attack of canker, which finally ulcerates through the drum and gains entrance to the cavity within.

Certain constitutional conditions and disturbances furnish predisposing causes for this affection. When the blood is impoverished and the system debilitated by long tedious illnesses, otitis is more prone to occur.

Symptoms

The disease almost always commences suddenly, attacking one ear, but never both at the same time. Pain which marks the invasion of the inflammation is intense and rapidly increasing in severity, eventually becoming so torturing as to cause the animal to shake his head violently, rub his ear along the ground, and utter incessant, sharp, shrill, ear piercing cries. He seems distracted and cannot be tranquillized.

These violent local symptoms are attended with disturbances of the general system, fever, hard and rapid pulse, great thirst, and entire loss of appetite. '

In some cases the animal seems delirious, so maddening is the pain which tortures him. Great tenderness exists on the affected side, and an examination will be made with difficulty. The passage to the ear will be found more or less reddened, swollen, dry, hot, and sensitive.

These painful symptoms may last five or six days; before the expiration of this time, death may in rare instances take place from convulsions, or possibly an extension of the disease to the brain.

If the animal lives, matter forms within the middle ear, and at last the membrana tympani ulcerates, or ruptures and pus streaked with blood is discharged by the external ear. This discharge is odorless at first but in three or four days becomes highly offensive.

After an opening is made the more violent symptoms subside. In some cases the discharge persists for a time and then disappears; the hole made in the membrane closes, and a cure is affected with but little loss of hearing. More commonly the small bones of the ear are discharged with pieces of other bones which have necrosed or been destroyed, and a cure takes place with almost a complete loss of hearing. In other cases the brain may become affected by the extension of the disease and death result.

In rare instances instead of the matter discharging through the external ear, it may so affect the deeper cells and structure that a swelling back of the ear appears; an abscess forms which eventually opens and thus allows the pus to escape.

During the progress of otitis the general system suffers severely, debility becomes marked, emaciation is progressive, the animal is slowly wearing out.

Treatment

The intense severity of the pain demands the use of opiates, and fifteen drops of laudanum should be given every two or three hours as needed. Hot applications if they can be made to the side of the head, may aid slightly in relieving the suffering. During the inflammatory stage, the bowels should be kept open by two or three teaspoonfuls of epsom salts given as needed. It is to be remembered the disease occurs more often in debilitated animals, and the effort to nourish and sustain should be early commenced.

If nourishment is not taken voluntarily, the sufferer should be forced to swallow concentrated beef tea, broths, milk, and raw eggs. Two grains of quinine may wisely be given three times a day. After the discharge appears, absolute cleanliness should be enforced. The ear should be gently syringed every two or three hours, and if much odor exists, the drops recommended in canker should be used after each injection. As the odor disappears, and if the discharge remains profuse, after syringing the ear with warm water, an astringent injection of alum and water, one half a drachm of the former to an ounce of the latter may he used.

If pieces of bone appear in the discharge, sulphate of copper five grains to an ounce of water may be injected instead of the alum.

After a time as a substitute for the medicated injections, boracic add may be freely dusted into the ear after a thorough syringing with warm water.

As the appetite returns the most nourishing diet should be allowed, consisting largely of raw beef Cod liver oil in dessertspoonful doses should be given three times daily, and instead of quinine, the citrate of iron and ammonia may be given in four grain doses with the oil.

By improving the tone of the blood, nourishing the body, and sustaining the strength of the animal, a cure of the local affection may be accomplished.