582 



DISEASES OF THE SKIN. 



Symptoms in the pig. In this animal follicular mange is 

 marked by pimples from the size of a grain of sand to that of a hazel- 

 nut, which soon become transformed into inflammatory tumors, 

 the dimensions of which progressively increase, and which, when 

 opened, leave large ulcerations of the skin (Csokor). Varioliform 

 efflorescences may be observed ; these have been the cause of con- 

 founding follicular mange with variola (Csokor). The disease 

 invades only the " soft regions," and those where the skin is thin : 

 the neighborhood of the groin, neck, sternal region, flanks, abdo- 

 men, and the inner aspect of the legs ; the upper part of the head, 

 the back, and the external fascia of the legs remain generally un- 

 touched. The inside of the pimples contains from 50 to 100 

 demodectes, that of large abscesses from 500 to 1000. The parasite 

 is found in it in all degrees of development (the demodex of the 

 pig is about twice as large as that of the dog) ; we may also find 

 '^cuirasses'' therein, derived from metamorphoses due to the acari. 

 Follicular mange of the pig is much more contagious than that of 

 the dog. 



Symptoms in other species. In the cat the eruption is gen- 

 erally localized on the head (nose, eyes, and ears); these symptoms 

 are the same as in the dog. In the ox Grimm observed a case in 

 which the whole surface of the body, with the exception of the 

 head and extremities, was covered with pustules of the size of a 

 pea, on the surface of which the hair had disappeared ; on com- 

 pressing these pustules, a thick and clammy pus, containing a large 

 number of demodectes, would run out of them. The animal was 

 very thin ; its development had been delayed. Various modes of 

 treatment were tried, but did not produce any improvement.^ 



Diagnosis. The localization of the trouble upon the head and 

 extremities, and the presence of reddish-blue pustules on these 

 regions, clearly characterize follicular mange, and enable us to 

 recognize it immediately. There are cases (squamous form) where 

 the diagnosis can only be established with certainty by microscopic 

 examination ; this is generally very simple, requiring but a few 

 moments. It consists in spreading between two lamellae the con- 

 tents of a pustule, and examining the preparation with an enlarge- 



1 In 1885 Railliet and Nocard observed a case of demodectic mange upon a two- 

 year-old buck which had been born and raised at the Alfort School. Demodectes ex- 

 isted in large numbers in pustules mainly located upon the costal region and the 

 flank. 



