THE HORSE IN SICKNESS AND DISEASE 383 



pus ; these imperfect granulations cannot fulfil the purpose 

 of building up muscle (flesh) or tissue while absorption 

 goes on, and a loss of substance ensues. Granulation ceases 

 to build up regularly ; absorption removes irregularly ; and 

 hence comes an uneven surface, more or less a hole, with 

 hard, irregular edges, called an ulcer. In most cases, ulcers 

 are attended with great irritability of system, which must 

 be attacked by opium or generous digestible food. The 

 general treatment of ulcers is to cleanse by means of a 

 poultice, then stimulate, and keep up the system by a 

 nutritious diet. 



Ulcers are often found of a greater extent internally than 

 externally, when the fluid which is secreted by them 

 absorbs in different directions, forming narrow pipes, the 

 sides of which are scirrhous, from which issues a glairy dis- 

 charge. These pipes are called sinuses by the surgeon. In 

 general cases, the longer an ulcer has lasted, the more diffi- 

 culty there will be to bring it back to a healthy state. The 

 external means employed for this purpose are usually 

 stimulating injections, or incision. Ulcers are apt to be 

 treated by farriers erroneously, by plugging up the sinuses. 

 When the caustic penetrates farther than was intended, 

 sloughing away the diseased and the healthy parts, the 

 true remedy is equally simple and effective ; namely, to slit 

 them up, and then to lay within the divided pipe a piece of 

 tow saturated with some caustic solution. By this means 

 the scirrhous lining will be cast forth, and that which was 

 a sinus will be converted into a simple wounc4 



FISTULiE. 



There are three fistulous disorders in the horse which 

 more particularly demand notice, and to these we shall 

 confine our attention : (1) Fistula of the Parotid Duct ; 

 (2) Foil-evil ; (3) Fistula of the Withers. 



FISTULA OF THE PAROTID DUCT. 



The outward sign of this disease is an unnatural outlet 

 for the saliva in some part of its passage. A recent wound 

 of the duct itself shows little more than an opening wet with 

 moisture, except when feeding, at which time the saliva will 

 pour or spirt from the aperture like blood from an artery. 



