ECZEMA. 



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6. The scabby stage (scabby rash of our animals). It is the result 

 of the desiccation of the exudate in all the moist forms of the dis- 

 ease. In many cases, and especially in the chronic form, scabby 

 eczema is related to squamous eczema, of which we have just spoken. 



These successive stages give an explanation of the multiple forms 

 of eczema. But this disease does not necessarily travel through all 

 these stages ; it may pass directly from the first to the last, and 

 there are cases where, having reached a certain phase, it remains 

 stationary ; we must point out that, upon the skin which is covered 

 with hair or pigmented, several stages which evolute very rapidly 

 may pass entirely unobserved ; such are especially the papular and 

 vesicular stages. 



We will now proceed to examine eczema in our different species. 



A. Eczema of the Dog. 



Eczema is the most frequent of the cutaneous diseases of the dog. 

 It is ordinarily located upon certain regions ; it is especially ob- 

 served along the dorsal column ; it starts at the base of the tail; 

 on the back or neck ; from these points it extends and radiates in 

 all directions. The external face of the legs and buttocks are often 

 affected, more rarely the abdominal and lower pectoral regions ; the 

 fold of the knee, the neighborhood of the elbow, and the extremity 

 of the calcaneum are also regions which are often affected. It is 

 localized upon the head in some rare cases. Old or very young 

 animals, pet dogs, and delicate subjects with fine skin, also fat ani- 

 mals, are particularly exposed to it. Concerning the races, the 

 rough-coated dogs, bulldogs, and Leonberg dogs seem to furnish 

 the largest contingent to the disease. 



Causes. Eczema is generally the result of an irritation of the 

 integument ; this irritation may come from shearing or clipping, 

 from repeated pressures and frictions exerted upon certain regions, 

 from dust, dirt, and parasites (fleas, lice, trichodectes), which often 

 abound in the dorsal region, the preferred location of eczema. 

 Frictions or washing with black soap occasion it in a great num- 

 ber of cases. The rôle of fungi in the genesis of eczema is very 

 incompletely known. Ziirn was the first to express himself 

 affirmatively concerning the mycotic nature of this disease. In 

 vesicles of the dog, opened with all proper precautions. Millier has 

 found micrococci ; he maintains that eczema may occur whenever 

 these parasites in considerable numbers reach a dirty skin, where 



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