ii66 DADD'S VEIERINARY MEDICINE AND SURGERY. 



and canals are filled with material resembling soft cheese, whicb 

 IS probably fatty matter. This occasionally degenerates into pus. 

 Dr. Gordon forwarded me, some time ago, the head of a horse 

 who had long been the subject of this malady. The transverse 

 diameter of the bones of both upper and lower jaw was very much 

 enlarged; the periosteum was very highly organized with blood- 

 vessels; the bones were softened and elastic, and could be easily 

 cut with a knife. On submitting them to the acid test, earthy 

 matter was found in excess, and, by burning them, it was found 

 that they contained very little animal matter ; hence we were led 

 to infer that the disease was one of mal-nutrition. The articular 

 surfaces of various bones, and sometimes all the bones of the body, 

 are often ulcerated and studded with incrustations. This explains 

 the why and wherefore of the sudden and tormenting pains which 

 animals suffer, and goes to show how little of benefit can be ex- 

 pected from the ordinary treatment, which is principally directed 

 to the enlarged jaws. 



On removing these diseased cartilages from the articulating 

 surfaces of the bones, the latter are found to be affected — in fact, 

 ulcerated. In some cases the ligaments and tendons are separated 

 by decomposition, or necrosis of bone, and the animal " breaks 

 down," as the saying is. 



The subjects of this disease sometimes show lameness in the 

 vertebral region, and in that of the head of the thigh bone. Iq 

 such cases, we may safely infer that the lameness is of an articular 

 character, and the interticular cartilages, as well as the surfaces of 

 the bones, are incrustated and ulcerated. In this condition, tbe 

 animal is liable to become useless, or " break down " at any mo- 

 ment. The following case will illustrate what is meant by break- 

 ing down : 



We were requested, a short time ago, by Prof. Muzzy, to ex- 

 amine an aged gray gelding, the subject of lameness in the hind 

 feet. Examination revealed considerable heat, tenderness, and 

 tumefaction around both the hind coronets, and both angles of the 

 lower jaw were much enlarged in their transverse diameters. We 

 advised the owner to let the animal have a run at grass. Accord- 

 ingly he was sent into the country about thirty miles, which wa» 

 too long a journey for him. A few days afterward. Prof. MuzzY 

 received a letter that the horse's strings (tendons) became loose, 

 tno he broke down and traveled on his fetlocks, ^nd was then 



