diseases of the digestive organs.

BONES—DISEASES AND ACCIDENTS. 289tieth day, according to age and strength of the animal, the fibro-cartilaginousstructure undergoes a change and is gradually convertedinto bone, forming a ferule on the outside and a plug on the inside,which serve to hold the part in position. In the fourth stage, extendingto about the sixth month, the whole of the new structure is convertedinto bone. The fifthstage, extending up to the end of the firstyear, the callus is absorbed, being no longer necessary, and the connectionbetween the cavities of the two bones is again established.Common complications.—The process of union just described is healthyand normal. Diseased conditions may at any time supervene duringthe treatment and render the operation unsuccessful. In the case ofcompound fracture, the open wound communicating with the ends ofthe bones, a septic condition is apt to arise which may become so seriousas to endanger the animal's life and bring about conditions whichin human surgery would indicate amputation. Although that operationis not a general one in veterinary practice, there is no reason whyit should not be attempted as a last resort, particularly if the animalbe valuable, or one whose existence is necessary in order to perpetuatesome valuable strain. Even in the simplest form of fracture, if thesplints or bandages are improperly applied and the fractured bone leftso loosely guarded that the broken ends move one upon another, theformation of the calluses previously described is likely to be interferedwith, and in place of a strong, rigid, and healthy union a formation ofelastic cartilage is the result. This false structure unites the brokenends of the bones in such a way that they move one upon another,depriving the bone of its stability and usefulness. When once thehealthy process of union is interrupted in the manner just described, itis with great difficulty that it can be again established. It no longerdoes any good to continue the restraining power; in fact, the changeof the temporary cartilage into bone is more likely to be reestablishedif the parts move violently upon one another for a short time so as toset up and renew the process of inflammation. Then if the restraintbe again applied there is some chance of union. In order as far aspossible to avoid this danger, care should be exercised that the bandagefitsclosely and that it is kept on till there is no longer any dangerbut that a perfect union has taken place. It is impossible to say atjust what time the splints or bandages can safely be removed. In ayoung and healthy animal of quiet temperament, where the parts havebeen firmly held in position throughout the whole time, from thirty toforty clays may be regarded as reasonably safe. Under more unfavorableconditions as to age, vitality, and restraint, the period had betterbe extended up to sixty days if the general condition of the animal issuch as to permit of so long a continuance. After the appliance hasbeen removed the animal should be allowed to stand quiet for a fewdays, then given very gentle exercise, gradually increased over a periodof a week or ten days, by which time the patient will be so far recovered24097 19