LXI. 



DISEASES OF THE EAR. 



CANKER. 



This disease affects principally the water dog, but no breed is 

 .exempt. It is frequently met with in the pointer and setter. 



Internal canker, otorrhaa, is an inflammation of the lining 

 membrane of the meatus auditorus externus, with a discharge of 

 purulent matter, sometimes mixed with blood, which may occa- 

 sionally coagulate, block up the tube and cause deafness. When 

 the disease extends to the internal ear it constitutes otitis, which 

 may end in death. The disease is local or constitutional. When 

 local, it is caused by the lodgement of dirt, water, or foreign mat- 

 ter in the ear. The constitutional arises from improper and over- 

 feeding, want of exercise, catarrhal affections, and the extension 

 of skin diseases. 



The earliest symptom of the approach of canker is frequent 

 shaking of the head, or holding the head to one side. The dog- 

 will scratch the ear violently. Redness of the integument lining 

 the annular cartilage may be observed, and this may be accom- 

 panied by an enlargement of the folds of the skin. If the case 

 be neglected, the pain will rapidly increase, the ear becoming 

 redder, and there will be a deposit of red or black matter in the 

 hollow of the ear. 



Treatment. — The ear should be thoroughly washed three 

 times a day with warm water and soap. A scniple of the extract 

 of lead to an ounce of water should be applied. The preparation 

 should be applied warm, and may contain a little tincture of 

 opium. A purgative should be administered in the first stages 

 and the animal kept on a cooling diet for a few days. The liquid 



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