There is a disease commonly called "canker within the ear," and another called "canker without the ear." The former consists of chronic inflammation of the membrane lining "the passage of the ear. Water-dogs are prone to be affected, and in treating them it is important not to expose them afresh to the exciting cause - damp and cold. But the disease is not confined to them, for it attacks those dogs that are fed on a flesh diet, or have little exercise, or that are pent up in a dirty place. It oftener attacks long-haired than short-haired dogs, and is always more severe and obdurate in the former than in the latter. A gross state of the system strongly predisposes to canker. Canker sometimes follows the disappearance of the eruption of mange; and after having been once cured is apt to return, unless great care be taken as to diet, exercise, etc.

Symptoms

Soon after internal canker begins, the dog is observed to be frequently or constantly shaking his head with considerable violence. This alone is a symptom that ought to strike the observer as indicating something amiss about the ear; it often, if not always, precedes the appearance of diseased action; so that when the dog is found to be frequently shaking his head, even in the absence of local disease, a good guess may be made as to what disease will shortly appear. The dog also frequently rubs and scratches his ears with his paw, and carries his head rather inclined to one side. On examining the ear, the membrane lining the passage is found reddened and inflamed; there is also some enlargement of the folds of the skin. At a later period, there is considerable pain where the flap of the ear is attached to the skull, and an accumulation of an offensive reddish or blackish discharge in the hollow of the ear. The parts are hot and generally thickened. The dogs thus affected appear to be temporarily deaf.

External Canker sometimes follows the internal. The constant shaking of the head and flapping and scratching of the ear causes irritation, which is followed by canker of the flap of the ear. In the first instance, there is merely a sore around the border of the ear; this sore receives great irritation from scratching, etc., and then the parts take on an unhealthy ulcerative action, which attacks the cartilage of the ear and extends in every direction. There is a considerable discharge of offensive matter from the ulcerated surface.

In some cases, these symptoms of external canker are preceded by thickening of the edges of the ear, on which is found a scurfy eruption. There are likewise some pain and much itching. Under the irritation caused by rubbing to relieve the pain and itching, the parts become sore and ulcerated, and even cankerous. Mange may either precede or accompany this condition of the ears.

In inveterate cases of canker, or in those which attack a dog weakened by ill-usage or by bad food, or in those that are aggravated by the use of severe caustic applications, it is usual for the inside and outside of one ear, or of both, to be affected at the same time. Under the drain of puriform matter, or the irritation of pain, the dog may sink from exhaustion.

When internal canker is neglected, or badly treated, the small bodies seen at the bottom of the meatus gradually acquire a considerable size, and block up the canal more or less completely. They are polypi.

Treatment

The treatment of the internal form of canker necessarily varies according to the stage of the disease. At first, when the part is simply inflamed - red, painful, and slightly swollen, a dose of Aconitum* should be given four times a-day, and continued until the subsidence of these symptoms. No local applications should be applied.

When the disease has gone a step further - that is, when there is a reddish or blackish discharge in the ear, probably indicating extension of the inflammation to the cuticle of the ear and to the ceru-minous glands, then the ear must be thoroughly fomented, and the accumulation must be removed by gently injecting lukewarm water into the ear by means of a caoutchouc syringe. The injection should be used as often as may be necessary; the parts wetted being afterwards thoroughly dried. Preparatory to these local measures, removal of the hair from the flap is advisable. If, after the removal of the discharge, the passage be found red and painful, Aconitum should be given as directed above. Should the discharge continue, or should the disease go on to ulceration, with secretion of pus, the injections of lukewarm water should still be resorted to, for the threefold purpose of relieving pain by the application of warmth, removing secretion which is apt to become offensive if allowed to remain, and securing cleanliness. In addition, Calendula lotion * should be used after each injection, and it should be first warmed, because the inflamed ear is extremely sensitive to impressions of heat or cold. To quote from Youatt, "two persons will be required to accomplish the operation (that of applying the lotion). The surgeon must hold the muzzle of the dog with one hand, and have the root of the ear in the hollow of the other, and between the first finger and the thumb. The assistant must then pour the liquid into the ear; half a teaspoonful will usually be sufficient. The sturgeon, without quitting the dog, will then close the ear, and mould it gently until the liquid has insinuated itself as deeply as possible into the passages of the ear." Unless these directions are fully carried into effect, the application will not reach the diseased part, and will consequently have no good effect. At the same time, the dog should have one grain of Merc, sol, first trituration, night and morning. In the majority of cases, this treatment will prove successful.

* For the dose, etc., consult the "Introductory Remarks".

* See Appendix.

A few exceptional cases, however, will probably resist this treatment, either because the disease is unusually stubborn in consequence of some constitutional depravity, or because it has been neglected in the more remediable stage. When there is extensive ulceration, with copious secretion of pus and a tendency to fungoid growth, Hydrastis In-fusion * is invaluable. The mode in which it should be applied has been already described. In this stage, Arsenicum - a dose three times a-day, and continued for several days - is of great service in setting up a more healthy local action by improving the impaired tone of the general system. Other indications for its use are, the co-existence of disease of the flap, whether mangy, scurfy, or cankerous, and loss of appetite and of flesh.

Should the morbid growths which are sometimes found in the more advanced stage of the disease be sufficiently large to admit of being removed, the polypus forceps should be applied to the base of each, and then the local application will more effectually reach the diseased part.

* See Appendix.

In external canker, - that involving the flaps of the ear, - the same internal and external remedies just recommended are equally efficacious in the respective stages of inflammation and ulceration. Internal and external canker are probably two forms of the same disease, but presenting different symptoms from the difference in the structure of the parts attacked by each. As the latter generally follows the former form in consequence of the dog shaking and irritating his ears, the cure of the one will of course aid in the spontaneous disappearance of the other; whilst the remedies employed will have a curative effect on the disease as a whole, when the two forms co-exist in the same animal. There was a time when sportsmen and knowing ones undertook, in blissful ignorance, to cure external canker by the summary process of "rounding" the dog's ears - that is, cutting off the diseased border, and thereby making the flap smaller. The ear thus maimed becomes as bad as, nay worse than, ever; for the ulceration returns in the cicatrix, and is found more difficult to cure than the original state. The knife is again plied, with the same results - greater deformity, greater cruelty - and then the dog is killed as incurable. The recurrence of the disease proves that it does not altogether depend on local morbid action, but on a constitutional cause that must be removed before a cure can be effected. Or, the disease of the flap may be re-excited by the contiguity of canker in the passage of the ear.

An important auxiliary in the treatment of canker is rest The ears, and especially the flaps of them, must be kept still; otherwise the constant fretting of the parts by movement and rubbing will keep up the disease in spite of all purely medicinal treatment. A cap should be put on the dog's head; and the cap can be made by following Youatt's direction. "A piece of strong calico must be procured, six or eight inches in width, and sufficiently long to reach round the head and meet under the jaw. Along each side of it must be a running piece of tape, and a shorter piece sewed at the centre of each of the ends. By means of these, the cap may be tightly drawn over the head, above the eyes, and likewise round the neck behind the ears, so as perfectly to confine them."

Food, Etc

The diet also requires attending to. At first no animal food must be allowed, only vegetables. When the dog is very low and reduced in flesh by the discharge it is necessary to reverse this rule.