DISEASES. 721 



cartilage; but, as in cartilaginous disease, the fistula is often sin- 

 uous, it is better to use a soft, flexible instrument, such as a fine 

 probe made of lead. The injection of Hquid may take the place 

 of the probing ; injected in a superficial tract, it returns outward 

 directly, while in deeper and irregular fistulfe, it will penetrate 

 more readily. The induration of the coronet, the rough and ramy 

 appearance of the hoof of the quarter corresponding to the fis- 

 tula, indicate generally a necrosis of the fibro-cartilage ; these 

 characters are missing in the furuncle. 



V. I'rognosis. — In consequence of the tenacity of the disease, 

 this form of quittor is always serious ; though this gravity has, in 

 our days, greatly diminished, on account of the means of treat- 

 ment now in use, which were unknown some thirty years ago. 

 Now, this affection, which was considered by aU hippiatrics as al- 

 most incurable and which more recently was treated by an opera- 

 tion which rendered the animal unfit for work for several months, 

 can in the majority of cases be cui-ed in about fifteen days. 



The prognosis, however, varies and depends on the compUca- 

 tion. When there is caries of the ligaments, inflammation of the 

 articulation of the foot, or of the sesamoid sheath, the extirpation 

 of the cartilage itself, done with the greatest dexterity, is not 

 even a warranty of recovery. It remedies only the necrosis of 

 the cartilage, but leaves the other diseased processes to progress 

 in such a manner that the animal remains worthless if he has not 

 to succumb to them. The pain is, besides the other signs, one of 

 the most important points to consider: very acute, it is generally 

 a discouraging omen, and points to the existence of serious com- 

 plications. 



VI. Etiology. — Heavy draught horses are more frequently af- 

 fected, on account of their peculiar work. The most common 

 cause is a bruise, a blow, a burn, a prick, any wound exposing the 

 cartilage; it is most common in horses drawing trucks loaded 

 with stones, which may drop on their feet and crush the fibro- 

 cartilage. The same cause exists for horses woridng in extensive 

 works of buildings, in the construction of railroads, and in the 

 shops of mechanic construction. 



Owing to these conditions, it is also more common in large 

 cities than in the country, and more frequent in stony and tem- 

 porary roads than in those which are smooth and flat. Flat feet, 

 with low heels, are more exposed than others, as well as those 



