446 DISEASES OF THE SKLY 



tablishing the correct prognosis, as no cure can be obtained until after 

 the cause of the trouble is removed. The first thing we must do is to 

 lessen the mechanical irritations, such as appear under the collar and 

 on the testicles. But the lesions which the patient inflicts upon himself 

 are of very much more importance, for we see it in all forms of itching 

 eruptions of the skin, in erythema, in cases of parasites of the cutaneous 

 membrane — flies, lice, acari — ^in great accumulations of dirt, scabs, and 

 falling out of the hair. "We also find attacks of eczema which extend 

 very fast, and in some cases may go all over the body. 



As regards the second group of agents which cause eczema, they 

 are chemical irritants, especially those which have an influence upon the 

 tissues, such as acids, alkalies, mixtures of mercury, also tar and car- 

 bolic salves, combinations of ether and oil of turpentine, of mustard, 

 and also tar-soap. 



The third group is formed by a number of thermic irritations, 

 namely, excessive high temperature, but not high enough to produce 

 vesicles. 



Eczema appears more frecpently in summer than in winter, and we 

 have a great deal more difficulty in healing it during the summer weather. 

 We also have a number of eczematous formations for which we can find 

 no cause. In such cases the disease has been ascribed to acids in the 

 blood or diseases of the nervous apparatus, and also to vegetable para- 

 sites, and as the sensible perspiration in the dog is so slight, it is very apt 

 to cause irritation when the skin becomes congested, checks the secretion 

 of the glands and retains the natural excretions. There is no doubt 

 that- various fermentative and toxic processes occurring in the intestinal 

 tract are factors in the production of eczema rubrum, and that dogs 

 have the disease annually, and associated with constipation. Ep- 

 pinger contends that too much meat is not the actual cause as he 

 has cases where the animal has had moist itching eczema and treated 

 the animal with various drugs without result, and finally gave the 

 animal a meat diet, and in two weeks the animal was entirely recovered. 

 This, however, must have been an individual case as experience is that 

 a strong meat diet is invariably one of the causes of this disease. 



Clinical Symptoms and Course. — Eczema may appear in any breed 

 of dogs and in any region of the body without regard to age, sex, etc. 

 It is usually seen on certain regions of the body (back, head, neck, and 

 external surface of the extremities). 



There are three general forms of eczema without taking into con- 

 sideration the changes which may be produced by irritation, scratching, 

 or rubbing. 



(1) Acute Moist Eczema. — This may develop year after year and 

 in dogs of all breeds. The longer haired clogs seem, however^ to be more 



