752 DISEASES AND THEIK TKEATMENT. 



Anchylosis of Bone. 



Anchylosis is simply extensive exostosis, in which we have the 

 ends of two or more bones united by bony matter, as shown in 

 ring-bone, spavin, splint, etc. 



Symptoms are enlargements round the joint, which is stifi'and 

 inflexible, and in some cases the animal is lame. 



Treatment. — If there is lameness, blister or fire, as may be 

 thought necessary^ so as to complete the union of parts. The mo- 

 tion of the joint cannot be restored by any treatment. 



Caries of Bone. 



Caries is generally defined to bo ulceration or disintegration of 

 the bony texture, and is supposed to be ulceration of the soft tis- 

 sues; but this is not, histologically speaking, correct. We find in 

 caries the bone undergoes several very marked changes. It de- 

 creases in density (owing to the decrease in the proportion of or- 

 ganic matters entering into its composition), and presents a peculiar 

 worm-eaten appearance, which enables us always to recognize a 

 carious bone in the dried state. See specimens in chapters on Na- 

 vicular-Joint Lameness, and Laminitis. 



Causes. — It may arise from whatever may produce inflannna- 

 tion of the bone, or arrests or suspends its nourishment. It is a 

 frequent sequel of fracture in the ribs, sometimes from neglect or 

 mismanagement of poll-evil, or fistula of the withers; in cattle, 

 sometimes from " foul of the foot." Whatever destroys the perios- 

 teum may produce caries. 



Sym.pto'ms. — The surrounding tissues are swollen ; there is an 

 opening into the diseased bone, from which acrid, bad-smelling 

 matter discharges, in which float specula3 of disintegrated bone. On 

 examining the bone, it presents a fungus, which readily bleeds 

 when touched; on pressing the finger into it, sharp processes of 

 bone are felt, which are the bone breaking up. The bone is easily 

 punctured with a probe or knife. 



Treatment. — This, in most cases, is a very tedious affair. In 

 the first place the wound must be freely opened, and the parts 

 toiiched with dilute hydrochloric acid several times a day. Min- 

 eral and vegetable tonics nmst be given. Where practicable, as 



