230 VETERINARY SURGICAL THERAPEUTICS, 
species, especially dogs, hygiene, food and condition of life may produce 
upon the genesis and march of eczematous affections. 
On the surface where flexion takes place in the lower articulations of the 
extremities, one observes, often in horses, a dermatitis, the principal de- 
termining causes of which are the irritation produced on the skin by cold 
water and mud, manure, dust or the application to these surfaces of oint- 
ments made of lard or of vesicating preparations (blister on the fold of 
the hock or of the knee); this dermatitis is sometimes under the in- 
fluence of an eczematous diathesis. The skin tumefies, becomes warm, 
painful, and covered with vesicles, which ulcerate; a serous, yellowish 
fluid exudes from the papillary layer, which, when the animal moves, 
cracks and forms fissures more or less deep, whose edges lose their hair 
and become indurated. The fluid secreted by these wounds dries on 
their surface, forming yellowish crusts. These cutaneous cracks (scratches) 
are not localized on the hollow of the fetlock only: they appear some- 
times behind the canon and alongside the tendons. 
Whatever be the seat of these lesions, ordinarily the leg is swollen, 
and complications of lymphangitis are frequent in recent scratches. 
The pain and the lameness, which are sometimes very great in nervous 
animals, are not so prominent in low-bred creatures. The transverse fis- 
sures of the knee (malanders) and of the hock (sadlenders) assume, in 
some cases, a scaly form, and are transformed into callous wounds. The 
fissures (scratches) of the canon and fetlock may terminate in the same 
way ; sometimes they give rise to hypertrophic dermatitis. 
The prophylaxis of these affections consists in keeping the lower 
regions of the extremities thoroughly clean, in protecting the skin from 
long contact with dampness, mud or irritating liquids, and in not cover- 
ing the fold of the joints with vesicating preparations or greasy mixtures, 
which become rancid, irritate the skin and dry on its surface. ‘ The 
practice of clipping the hair of the fetlock in winter and during the 
rainy season is the cause of many scratches. On this account, advice 
should always be given not to do this in winter on horses which in working 
are obliged to stand in mud or are kept outdoors a long time’ (Weber). 
When the hairs of the extremities are clipped, the legs ought to be 
washed with tepid water and well dried before the animal is returned 
to its stall. 
The curative treatment varies with the stages of the disease. A most 
varied assortment of drugs has been recommended: poultices, tincture of 
aloes, iodated glycerine, white lotions, egyptiacum and the Villate solution‘ 
all have their patrons. ‘To all those agents we prefer careful disinfection 
* Weber, Bulletin de la Soc, Cent. de Med, Vet., 1889, p. 314, 
