PRINCIPLES OF VETERINARY SURGERY 369 



Under these conditions, it is easily conceived how trivial 

 may be the causes responsible for the starting of ulcerating 

 sores. 



SYMPTOMS. — An ulcer may start with a cutaneous 

 excoriation, an abscess, or an eruption. Its aspect is essen- 

 tially variable according to the age of the lesion and the 

 amount of oedema of the region. When the part is oedema- 

 tons the ulcer is depressed and spongy in appearance, and 

 the sound skin shows a striking tendency to expand over it. 

 The bottom is indented, greyish, and covered with little 

 hjemorrhagic spots. The granulations on the surface are 

 soft, translucent and verging on necrosis. 



When the lesion is old, the ulcer becomes inactive and is 

 surrounded by a fibrous tissue that is very hard, very consist- 

 ent, sclerotic and lardaceous, constituting the lesion known 

 as callous ulcer. Its edges are cut perpendicularly, are hard- 

 ened and devoid of all mobility. 



When certain phenomena of gangrene appear at the level 

 of the ulcer and the process spreads so as to destroy every 

 tissue it encounters the lesion is known a phagadenlc ulcer. 

 (Fig. 34). Ulcerous sores with a pale, smooth, pultaceous, 

 greyish back-ground and without granulating elevations are 

 known as atonic ulcers. Those which bleed easily are desig- 

 nated as haemorrhagic ulcers, and those which have been 

 keenly sensitive from the beginning are called irritable ulcers. 

 In all varieties the surrounding skin is hard and smooth. 

 (Fig. 35). Their evolution is extremely slow and irregular, 

 and they usually develop without pain, but may impede loco- 

 motion, and the ability to support weight, and they gen- 

 erally present symptoms of improvement and aggravation 

 alternately. Spontaneous recovery is rare. 



DIAGNOSIS AND PROGNOSIS.— The determination 

 •of the disease is simple enough, but the estimation of its 

 exact proportions is often surrounded with real difficulties. 



