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DISEASES OF THE SKIN. 



Traumatic cases of grease, observed bj Straub on army horses 

 after manœuvres in stubble fields, have more analogy with infec- 

 tious dermatitis than simple eczema. Similar lesions to that of 

 grease may be produced by a large number of superficial wounds 

 giving place to a secondary erysipelatous or phlegmonous inflamma- 

 tion. An infectious dermatitis is, too, very often developed in the 

 course of creviced leg grease ; it is due to the penetration of septic 

 matters into wounds formed by the tearing of the vesicles, and into 

 the fissures of the skin. 



Symptoms. The acute form of grease^ malanders and salanders, 

 is indicated by typical symptoms. The skin is at first red, tume- 

 fied, painful and hot (erythematous state) ; it is soon covered with 

 small vesicles (vesiculous state) which burst and discharge a serous, 

 yellowish liquid, which is at first without odor (damp condition). 

 The integument, by the movements of the animals, is formed into 

 thick folds, between which crevices are formed (rhagades), the edges 

 of which become inflamed and covered with dry scabs. The hairs 

 are agglutinated, erect, or have fallen out in large quantity. The 

 movements of the corresponding member are stiff and painful. 



At this period the salanders and malanders may become healed 

 or pass into a squamous state ; in this latter case the skin becomes 

 thickened, the trouble has a tendency toward the chronic condition, 

 and returns of the disease are frequent. Grease produces in the 

 course of time serious alterations in the pastern. The excreted 

 liquid becomes decomposed and macerates the epidermis ; a kind of 

 viscous, doughy exudate is formed, which is of bad aspect, of fetid 

 odor, is possessed of irritating properties, and gives rise to ulcerat- 

 ing losses of substance in the skin. The pastern fold becomes also 

 the seat of granulating wounds, more or less extended, also of cal- 

 lous embossed thickening of the skin, which is aflected by fissures 

 or deep crevices (a condition formerly designated under the names 

 of ^' tuberculous disease" and '^callous leg grease).'' The hairs are 

 erect, standing like bristles. After months or years, cutaneous 

 hypertrophy may be transformed into true elephantiasis, in which 

 case the surface of the skin remains the seat of chronic squamous 

 eczema (squamous grease).^ The integument is sometimes tumefied 



1 Elephantiasis {elephantiasic Jibroma) or pachydermia is essentially characterized by 

 hypertrophy of the skin and subcutaneous connective tissue. It occurs usually after 

 inflammatory obstruction or reiterated œdematous infiltrations. In the horse it is 

 quite commonly found on the hind legs, mostly on one only, sometimes upon both. 



